[GMCnet] Trouble adjusting parking brake
Larry Engelbrecht
I'm having trouble getting sufficient "hold" with the parking brake in the up position AND having minumum/no drag in the released position. I've tried balancing cable tension side to side and between middle and rear wheels.
All cables have been lubed and work smoothly, including in the cable housings. All brake parts are there. I've muscled the U-turn brake cable adjuster dealy to better even out the cable tension, both the front one and both rear side ones. I either get a wheel to lock up too quickly or drag or I get nothing if I adjust so they don't drag. I thought I had the star wheels lubed, adjusted, and correctly oriented (Jim K, are you listening?), when I was recently in there.
Any suggestions?
--
Larry Engelbrecht
'73 26' ex-Glacier
TZE063V100319 030773
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Bob Heller
Larry,
This is just my opinion, but you will never have a good parking brake using the factory setup. I went through the same issues a couple of years ago and no matter how clean and smoothly operating all the components were there was no way to have the parking brake BOTH hold the coach properly and release completely, like a proper parking brake system should. There is a kit that some GMC vendors sell that replaces the factory linkage parts with pulleys and rods and other stuff, but since my last name isn't Trump I had to find a more affordable solution.
There are two issues, one is that the cable return springs in each wheel are not quite strong enough given the amount of cable and associated bits on the rest of the system (easy issue to fix), and the other is not enough travel in the lever assembly in the coach so you can apply enough force to the brake shoes (harder to fix).
The cable return springs can be assisted by external springs at the u-shaped adjuster things on either side. It doesn't take much additional spring tension to reliably retract the brake shoes fully. I can't remember whether the springs I used came from an auto parts store or from Lowes or Depot. That took care of the dragging-shoes problem.
I looked at replacing the handle assembly with a foot pedal or a t-handle type actuator. I hadn't found anything workable when I won a 4" diameter 8" throw air cylinder on Ebay for something like $27. Long story short, I used that air cylinder which is bolted to the right frame to push the cable. It is way overkill for the application but the price was right. Total parts were the air cylinder, a dashboard air switch (something like $15), a Harbor Freight air pressure regulator ($6), some air tubing, and several other small parts. Something like $60 total. The parking brake now holds great and releases completely and sounds neat when you flip the air switch to release the brakes.
I found that about 35psi holds the coach just fine. With that big of an air cylinder I would probably bend parts if I used the full 120+ psi from the air system. I don't think a 4" cylinder is needed and something smaller may work out better but that was what I had to work with. Maybe even using 2 small cylinders, 1 on each side and eliminating the big u-cable would work.
Again, just my opinion and JWID. All I know is that I move the switch one way and the brakes come on and actually WORK, and I move the switch the other way and the brakes turn off and there is no drag whatsoever on the rear wheels. And the price was right.
--
Bob Heller
1974 X-Canyonlands 26ft
Winter Springs FL
Rob Mueller
This is a great idea!
I'll have to check to see if it meets the requirements of the Department of
Transport / Roads and Traffic Administration here in New South Wales.
Rob Mueller
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426
-----Original Message-----
From: gmclist...@temp.gmcnet.org
[mailto:gmclist...@temp.gmcnet.org] On Behalf Of Bob Heller
Sent: Wednesday, 11 November 2009 6:53 AM
To: gmc...@temp.gmcnet.org
Subject: Re: [GMCnet] Trouble adjusting parking brake
Larry,
I used that air cylinder which is bolted to the right frame to push the
cable. The parking brake now holds great and releases completely and sounds
neat when you flip the air switch to release the brakes.
Norm Bowker
Bob, I ditto Rob but what happens when the air leaks off? Does the manual park brake hold?
Dan Gregg
Bob, I would like to see that set up. I have new cables and everything is tight. I can drive off and never feel a thing so I rarely pull it on. Takes all the grunt I have to pull it.
I have thought about the other "kit" but 500 bux is way over my budget.
Dan
--
Dan & Teri Gregg
///Halon Automatic Fire Extinguishers
Jim Galbavy
Larry,
I had similar problems a couple years ago. It was so bad that I was going to just disconnect the parking brake, but then I couldn't have passed the state inspection. Turned out to be a bad cable. I talked to Jeff Sirum and ended up buying a new cable from him (and it's mirror). Cleaned out the 30 years of gunk from the other cables and haven't had a problem since. The trick is to use the PB when ever you park and lube them when you change you oil and lub the chassis. Oh, and where I take the coach for state inspection, they set the parking brake, start the engine, put the slector to D and gun it. When I asked him what would happen if the PB didn't hold and he hit something? ... all he said was that why I have liability insurance on my coach.
jim galbavy
'73 X-CL (ANNIE)
Chesterfield, Va
sparkchaser
Last spring I replaced the park brake cables with Al Branscombe's park brake set the old OEM cables just didn't hack it for me. Now with Al's set I can hold the coach up to 1700 rpm and they are much easier to engage. And Al says you will have park brakes that work.
Dennis & Pia Lepard
Depew, NY
'76 Palm Beach
Thomas Phipps
To get enough pull on the barking brake cable, I had to go to the Ragusa handle extension. The air cylinder idea sounds neat. And the additional springs are also a good idea. Jim, registar as a Virginia Antique (GMC, not you) and no more inspections.
Tom Phipps
Larry
I found that about 35psi holds the coach just fine. With that big of an air cylinder I would probably bend parts if I used the full 120+ psi from the air system. I don't think a 4" cylinder is needed and something smaller may work out better but that was what I had to work with. Maybe even using 2 small cylinders, 1 on each side and eliminating the big u-cable would work.
___________________________________________________________
The Parking Brake (PB) has been one of my issues also.
Do you use the spring action to set the brake when the air pressure is off? That, if I am not mistaken, is how the truck trailers do it.
Air on, the PB is off and you travel. Air off, the spring sets the brake and you go now where, hopefully.
did you make your own cables?? Mine are shot.
Can I make my own ends? such as in the brakes?
You have given me ideas I just don't know how well this can be constructed.
If you would like to discuss more, I hope you might, you can contact me off site, or on site. Thanks
SLawrence111(at)Yahoo(dot)com
--
Gatsbys' CRUISER :d
74 GLACIER X, 260
455/APC/4 bagg'r(ver3)
Remflex Manifold gaskets
_______________________________________________
Purchased 08-18-04
_
Bill Massey
bdub
-----Original Message-----
From: On Behalf Of sparkchaser
Sent: Wednesday, November 11, 2009 7:52 AM
Last spring I replaced the park brake cables with Al Branscombe's park brake set
the old OEM cables just didn't hack it for me. Now with Al's set I can hold the
coach up to 1700 rpm and they are much easier to engage. And Al says you will
have park brakes that work.
Dennis & Pia Lepard
Bob Heller
Let me see if I can answer all the questions.
The original handle assembly is still there and fully functional, I just keep the adjusting knob fully counterclockwise to loosen the main cable. If I want to use the handle I just turn the adjusting knob in about 10 turns or so and then lift the handle and it works just like it always did. The only problem with the original setup is if you adjust the tension tight enough to really clamp the wheels then it doesn't release all the way and the rear brakes drag, not to mention you have to be a bodybuilder to set the handle tightly. I have a Ragusa handle extension but if you use it's lock screw then you cannot easily get to the adjustment knob. If you don't use the Ragusa lock screw then you run the risk of the extension handle flying off just as you're putting lots of force on it and then you then mash your knuckles into the dashboard. Fun. If they had made the handle assembly have maybe another half inch of cable travel it would probably work fine. There is a lot of cable in t
he original system and cable stretches, slightly, but it still stretches when tensioned. The air cylinder just has lots of travel relative to the original actuator setup.
I added the external springs because I want the springs in the wheels to pull back the rear cables and let the external springs pull back the rest of the cabling. On my coach one side cable was replaced and the other one is an original in good shape. When I was re-doing the rear brakes a couple of years ago I removed both side cables and cleaned and lubed them. They slide smoothly and don't drag any more than you would normally expect. The factory springs aren't quite strong enough to reliably retract all the brakes fully. Notice I said 'reliably'. I don't want ANY drag from my rear brakes so I used just enough external spring tension to make darn sure all the brakes retracted fully each and every time.
The air cylinder applies the brake. If you lose air pressure the brake will release. The compressor runs for about 30 seconds every 90 minutes or so and always has since the day I bought the GMC. The parking brake setup hasn't changed a thing. Some day I will find the air leaks, but it's not on the top of my things-to-do list. My compressor runs off the house battery so there's plenty of electricity. I have a switch on the dash and usually turn off the air system when I'm not using the GMC. I don't need a parking brake where it's stored so there's no reason to leave it on for an extended period. Really, the only time I need a parking brake is if I stop somewhere and have to park on an incline. I obviously won't be camping with the coach off-level by much so when I actually use the parking brake it's not for days-at-a-time. If it were, I would just use the original handle actuator with the adjustment knob cranked down.
I bolted the air cylinder to the inside of the right-side frame, just behind where the main pb cable goes through the frame on the right side. The only modifications to the GMC were to make the slot the cable runs through a bit longer and to remove the cable guide rod that goes from the cable to the right front crossmember. I adjusted the main cable at each side to take up the slack. That's it. If I want to go back to 'stock' I just unbolt the air cylinder, reattach the cable guide rod, and adjust the main cable at each side. The only 'custom' part is a kind of hook-shaped thing I made to bolt onto the plunger of the air cylinder so it grabs the cable and pushes it towards the front.
I've only tried up to about 40 psi of air pressure and it holds the GMC fine. I don't want to break cables or other parts so I'm not going to try and see what happens if I crank up the pressure. Someone else can do that experiment!
The kit that Al Branscombe makes looks great. I would love to have one, but it just comes down to money. I guess I picked the wrong family to be born into! I had to make do with what I could find and within a certain price range. If I hadn't found that air cylinder on Ebay for the price I did then I'd still be trying to figure out how to get a pedal-operated mechanism to work.
Dan, I did that once. I thought the GMC was a bit lacking for power one day and since my 'brake' dash light doesn't work all the time I forgot to release the parking brake. Thankfully I only went about a half mile at low speeds before I looked down and saw the brake handle up. That won't happen now, it's really obvious when the parking brake is on!
Hope that answers everything!
--
Bob Heller
1974 X-Canyonlands 26ft
Winter Springs FL
Albert&Sheila Branscombe
Hi All from the " Northland"
It seems there are those who believe our stainless park brake assemblies are out of line price wise. Just a note to explain the whys and wherefores as to why they have to be the price they are. A couple of nights ago " The Donald" (NOT!) and one of his meandering buddies appear to have implied that the kits are the ultimate in overkill and expensive.
This observation could hold some merit if we only sold parkbrake kits in Texas, Oklahoma or Arizona but unfortunately this is not the case. We would happy if we did not have to take into account corrosion issues and as such could cut the kit price by at least 33% perhaps more, BUT of course you can go down to your local auto parts store and buy that kind of park brake components. In fact that's what was done for 30 or so years until our stainless kits became available in 2005. If you are near the sea , in the northern states , Canada or England , then corrosion protection is a must.
Believe me , anodized aluminum and stainless steel are expensive and as such the kits are on the pricey side. However take a few minutes and check the prices of park brake components of a major GMC supplier in Florida ( not Jim or Jeff) and you'll be shocked at the price for 4 conduit assemblies and an intermediate cable. Nearly $500.00 and no stainless , no teflon, no anodized pulleys , etc. , A builder in Michigan is better but not vastly.
We have approx. 106 kits out there and 106 happy customers and hopefully the remaining 94 will be as happy, we bought equipment to do 200 kits so we're half way there . If one is going to give a 10 year warranty on material and workmanship , then you must have a superior product, the standard warranties on park brake components are typically 90 days to 6 months, hmmmm, why do you suppose this is ? Our paper work states a 10 year warranty but in actual fact as long as I exist the kits are warranty covered to the original owner . The only damage not covered is items that have been destroyed in an accident.
The same philosophy applies to the air assist actuator and a new 65 mm hydraulic/ mechanical caliper that we are prototyping. The installation has to be DOT approved and a legal entity anywhere its used. This type of engineering and manufacturing and component testing does not come cheap , and as such the costs are passed on to the customer. We are proud of our product and pleased that we can provide components at a fair price for those that require them. Cheers all and hope to see you down the road.
Albert Branscombe
Kerry Tandy
Brakes. Let me know when you come up with something else.
Kerry Tandy
Bewartz Farms
Gold Canyon, AZ
Efax-253-563-2514
To see where we are now, click on
http://map.datastormusers.com/user1.cfm?user=38
http://www.satellitefriendly.com/user/info.php?id=bewartz
Blog:http://bewartz1.blogspot.com/
Pray Incessantly!!!
Tim Conway
On Nov 11, 2009, at 9:08 PM, Kerry Tandy wrote:
> Very Good, Albert. I am sincerely extremely Happy with My/Your
> Brakes.
Me too...
Tim Conway
LI NY 78 PB
Steve Southworth
78 Barbi wrote on Wed, 11 November 2009 18:56
> Hi All from the " Northland"
> It seems there are those who believe our stainless park brake assemblies are out of line price wise. ...
>
> snip
>
> ... Albert Branscombe
I am in the process of rebuilding my brakes, including the parking brake. Included with my GMC were several parking brake cables. I ordered what else I needed to complete the job. Most all my parts will now be new. Looking at the work involved and the $$ I have in it, I believe I would have been able to sell what parts I have and gotten Branscombe's kit and been way ahead in time, not too far behind in $ and way ahead in quality. Bottom line, if I knew then what I know now I would have bought the kit. Don't forget, the kit has several improvements over the original design.
--
Steve Southworth
1974 Glacier TZE064V100150
Palmyra WI
Jim Galbavy
Tom,
I actualy like to get the GMC inspected every year. Sort of like a forced savings plan, otherwise I might let the maint. slde and that's not good.
jim galbavy
'73 X-CL (ANNIE)
Chesterfield, Va
Larry
The same philosophy applies to the air assist actuator and a new 65 mm hydraulic/ mechanical caliper that we are prototyping. The installation has to be DOT approved and a legal entity anywhere its used.
_____________________________________________________________
Would you happen to have a site for the DOT document?
I have an idea I have played with but we have to stay legal, hadn't we?
--
Gatsbys' CRUISER :d
74 GLACIER X, 260
455/APC/4 bagg'r(ver3)
Remflex Manifold gaskets
_______________________________________________
Purchased 08-18-04
_
Albert&Sheila Branscombe
Hi Larry C.,
There are as many DOT documents as Carters has pills, the’re everywhere, if you were to use a brake rotor for instance from Brembo, TRW or PBR then you would get the appropriate approval number for that piece of equipment from them, notwithstanding it has to be used for the purpose intended and within the guidelines of its particular design capabilities. In our case where we had to manufacture our brackets, we had them tensile strength tested , doucumentated and PE stamped.
The replacement part must meet or exceed OEM equipment specs, a lot of these terms tend to be blanket statements and as such help poor lawyers to provide and feed themselves. With regards to an engineering structural analysis of the GMC Motorhome park brake setup, it didn’t take a lot of imagination to conclude that the weak point was the “ thru frame S - hooks” , they in fact had a negative safety factor number. I consistently use 3.5 as an acceptable safety factor.
In the case of our actuator , it is a power assist apparatus and complements the OEM handle setup, if it should fail for some reason, the full OEM capability is still there, therefore making it a legal entity. It still went thru all the testing the park brake kits were put to because of “due diligence” but it is not part of the mechanism that keeps your coach stationery on a hill. The cylinder depressurizes about 2 seconds after you toggle in the handle and let your foot off the service brake.
With regards to the ( possible ??? ) prototype hydraulic /mechanical caliper , it will have a DOT number from the manufacturer due to the fact that it was used on some of the Beaver Monaco coaches that weighed substantially more than ours . Our coaches at 12000 pounds or so are in the range of vehicles today that primarily use air brakes. We may never find a mechanical caliper that fully qualifies as a park / emergency brake . Reasonably decent park brakes can be achieved with drums due to the duo-servo action but discs are a completely different story. The Eldorado calipers were barely suitable for the Caddy, Riveria and Toranado except under ideal circumstances, why should we think for one minute that they should work for us ?
Excuse my rambling, hope this helps a bit, but with that said; Goodness help us if we ever “ T-Bone” a bus load of kids with our modified GMC’s , myself being just a guilty as the next one.
Cheers................Albert
Hi Larry C.,
There are as many DOT documents as Carters has pills, the’re everywhere, if you were to use a brake rotor for instance from Brembo, TRW or PBR then you would get the appropriate approval number for that piece of equipment from them, notwithstanding it has to be used for the purpose intended and within the guidelines of its particular design capabilities. In our case where we had to manufacture our brackets, we had them tensile strength tested , doucumentated and PE stamped.
The replacement part must meet or exceed OEM equipment specs, a lot of these terms tend to be blanket statements and as such help poor lawyers to provide and feed themselves. With regards to an engineering structural analysis of the GMC Motorhome park brake setup, it didn’t take a lot of imagination to conclude that the weak point was the “ thru frame S - hooks” , they in fact had a negative safety factor number. I consistently use 3.5 as an acceptable safety factor.
In the case of our actuator , it is a power assist apparatus and complements the OEM handle setup, if it should fail for some reason, the full OEM capability is still there, therefore making it a legal entity. It still went thru all the testing the park brake kits were put to because of “due diligence” but it is not part of the mechanism that keeps your coach stationery on a hill. The cylinder depressurizes about 2 seconds after you toggle in the handle and let your foot off the service brake.
With regards to the ( possible ??? ) prototype hydraulic /mechanical caliper , it will have a DOT number from the manufacturer due to the fact that it was used on some of the Beaver Monaco coaches that weighed substantially more than ours . Our coaches at 12000 pounds or so are in the range of vehicles today that primarily use air brakes. We may never find a mechanical caliper that fully qualifies as a park / emergency brake . Reasonably decent park brakes can be achieved with drums due to the duo-servo action but discs are a completely different story. The Eldorado calipers were barely suitable for the Caddy, Riveria and Toranado except under ideal circumstances, why should we think for one minute that they should work for us ?
Excuse my rambling, hope this helps a bit, but with that said; Goodness help us if we ever “ T-Bone” a bus load of kids with our modified GMC’s , myself being just a guilty as the next one.
Cheers................Albert
Hi Larry C.,
There are as many DOT documents as Carters has pills, the’re everywhere, if you were to use a brake rotor for instance from Brembo, TRW or PBR then you would get the appropriate approval number for that piece of equipment from them, notwithstanding it has to be used for the purpose intended and within the guidelines of its particular design capabilities. In our case where we had to manufacture our brackets, we had them tensile strength tested , doucumentated and PE stamped.
The replacement part must meet or exceed OEM equipment specs, a lot of these terms tend to be blanket statements and as such help poor lawyers to provide and feed themselves. With regards to an engineering structural analysis of the GMC Motorhome park brake setup, it didn’t take a lot of imagination to conclude that the weak point was the “ thru frame S - hooks” , they in fact had a negative safety factor number. I consistently use 3.5 as an acceptable safety factor.
In the case of our actuator , it is a power assist apparatus and complements the OEM handle setup, if it should fail for some reason, the full OEM capability is still there, therefore making it a legal entity. It still went thru all the testing the park brake kits were put to because of “due diligence” but it is not part of the mechanism that keeps your coach stationery on a hill. The cylinder depressurizes about 2 seconds after you toggle in the handle and let your foot off the service brake.
With regards to the ( possible ??? ) prototype hydraulic /mechanical caliper , it will have a DOT number from the manufacturer due to the fact that it was used on some of the Beaver Monaco coaches that weighed substantially more than ours . Our coaches at 12000 pounds or so are in the range of vehicles today that primarily use air brakes. We may never find a mechanical caliper that fully qualifies as a park / emergency brake . Reasonably decent park brakes can be achieved with drums due to the duo-servo action but discs are a completely different story. The Eldorado calipers were barely suitable for the Caddy, Riveria and Toranado except under ideal circumstances, why should we think for one minute that they should work for us ?
Excuse my rambling, hope this helps a bit, but with that said; Goodness help us if we ever “ T-Bone” a bus load of kids with our modified GMC’s , myself being just a guilty as the next one.
Cheers................Albert
Hi Larry C.,
There are as many DOT documents as Carters has pills, the’re everywhere, if you were to use a brake rotor for instance from Brembo, TRW or PBR then you would get the appropriate approval number for that piece of equipment from them, notwithstanding it has to be used for the purpose intended and within the guidelines of its particular design capabilities. In our case where we had to manufacture our brackets, we had them tensile strength tested , doucumentated and PE stamped.
The replacement part must meet or exceed OEM equipment specs, a lot of these terms tend to be blanket statements and as such help poor lawyers to provide and feed themselves. With regards to an engineering structural analysis of the GMC Motorhome park brake setup, it didn’t take a lot of imagination to conclude that the weak point was the “ thru frame S - hooks” , they in fact had a negative safety factor number. I consistently use 3.5 as an acceptable safety factor.
In the case of our actuator , it is a power assist apparatus and complements the OEM handle setup, if it should fail for some reason, the full OEM capability is still there, therefore making it a legal entity. It still went thru all the testing the park brake kits were put to because of “due diligence” but it is not part of the mechanism that keeps your coach stationery on a hill. The cylinder depressurizes about 2 seconds after you toggle in the handle and let your foot off the service brake.
With regards to the ( possible ??? ) prototype hydraulic /mechanical caliper , it will have a DOT number from the manufacturer due to the fact that it was used on some of the Beaver Monaco coaches that weighed substantially more than ours . Our coaches at 12000 pounds or so are in the range of vehicles today that primarily use air brakes. We may never find a mechanical caliper that fully qualifies as a park / emergency brake . Reasonably decent park brakes can be achieved with drums due to the duo-servo action but discs are a completely different story. The Eldorado calipers were barely suitable for the Caddy, Riveria and Toranado except under ideal circumstances, why should we think for one minute that they should work for us ?
Excuse my rambling, hope this helps a bit, but with that said; Goodness help us if we ever “ T-Bone” a bus load of kids with our modified GMC’s , myself being just a guilty as the next one.
Cheers................Albert
Hi Larry C.,
There are as many DOT documents as Carters has pills, the’re everywhere, if you were to use a brake rotor for instance from Brembo, TRW or PBR then you would get the appropriate approval number for that piece of equipment from them, notwithstanding it has to be used for the purpose intended and within the guidelines of its particular design capabilities. In our case where we had to manufacture our brackets, we had them tensile strength tested , doucumentated and PE stamped.
The replacement part must meet or exceed OEM equipment specs, a lot of these terms tend to be blanket statements and as such help poor lawyers to provide and feed themselves. With regards to an engineering structural analysis of the GMC Motorhome park brake setup, it didn’t take a lot of imagination to conclude that the weak point was the “ thru frame S - hooks” , they in fact had a negative safety factor number. I consistently use 3.5 as an acceptable safety factor.
In the case of our actuator , it is a power assist apparatus and complements the OEM handle setup, if it should fail for some reason, the full OEM capability is still there, therefore making it a legal entity. It still went thru all the testing the park brake kits were put to because of “due diligence” but it is not part of the mechanism that keeps your coach stationery on a hill. The cylinder depressurizes about 2 seconds after you toggle in the handle and let your foot off the service brake.
With regards to the ( possible ??? ) prototype hydraulic /mechanical caliper , it will have a DOT number from the manufacturer due to the fact that it was used on some of the Beaver Monaco coaches that weighed substantially more than ours . Our coaches at 12000 pounds or so are in the range of vehicles today that primarily use air brakes. We may never find a mechanical caliper that fully qualifies as a park / emergency brake . Reasonably decent park brakes can be achieved with drums due to the duo-servo action but discs are a completely different story. The Eldorado calipers were barely suitable for the Caddy, Riveria and Toranado except under ideal circumstances, why should we think for one minute that they should work for us ?
Excuse my rambling, hope this helps a bit, but with that said; Goodness help us if we ever “ T-Bone” a bus load of kids with our modified GMC’s , myself being just a guilty as the next one.
Cheers................Albert
Hi Larry C.,
There are as many DOT documents as Carters has pills, the’re everywhere, if you were to use a brake rotor for instance from Brembo, TRW or PBR then you would get the appropriate approval number for that piece of equipment from them, notwithstanding it has to be used for the purpose intended and within the guidelines of its particular design capabilities. In our case where we had to manufacture our brackets, we had them tensile strength tested , doucumentated and PE stamped.
The replacement part must meet or exceed OEM equipment specs, a lot of these terms tend to be blanket statements and as such help poor lawyers to provide and feed themselves. With regards to an engineering structural analysis of the GMC Motorhome park brake setup, it didn’t take a lot of imagination to conclude that the weak point was the “ thru frame S - hooks” , they in fact had a negative safety factor number. I consistently use 3.5 as an acceptable safety factor.
In the case of our actuator , it is a power assist apparatus and complements the OEM handle setup, if it should fail for some reason, the full OEM capability is still there, therefore making it a legal entity. It still went thru all the testing the park brake kits were put to because of “due diligence” but it is not part of the mechanism that keeps your coach stationery on a hill. The cylinder depressurizes about 2 seconds after you toggle in the handle and let your foot off the service brake.
With regards to the ( possible ??? ) prototype hydraulic /mechanical caliper , it will have a DOT number from the manufacturer due to the fact that it was used on some of the Beaver Monaco coaches that weighed substantially more than ours . Our coaches at 12000 pounds or so are in the range of vehicles today that primarily use air brakes. We may never find a mechanical caliper that fully qualifies as a park / emergency brake . Reasonably decent park brakes can be achieved with drums due to the duo-servo action but discs are a completely different story. The Eldorado calipers were barely suitable for the Caddy, Riveria and Toranado except under ideal circumstances, why should we think for one minute that they should work for us ?
Excuse my rambling, hope this helps a bit, but with that said; Goodness help us if we ever “ T-Bone” a bus load of kids with our modified GMC’s , myself being just a guilty as the next one.
Cheers................Albert
Albert&Sheila Branscombe
OMG, I apologize , I don't know how 4 copies of the doc. got uploaded, sometimes I feel like I'm lying in the ditch along side the information super highway, can anyone fix that. Moderator HELP !
Cheers....Albert
Larry
Just look at the bottom of the page, there is a button that says [ EDIT ]
Click that, then hilight all that you want to get rid of then hit [DELETE]
Thats it.
btw
Do you know how much psi ( in lbs ) is required to set the Parking Brake???
I don't think the handle by the dash is real reliable in that matter.
thanks
--
Gatsbys' CRUISER :d
74 GLACIER X, 260
455/APC/4 bagg'r(ver3)
Remflex Manifold gaskets
_______________________________________________
Purchased 08-18-04
_
Albert&Sheila Branscombe
Hi Larry,
Thanks, It's a case of not following the old saying of " Measure twice; CUT ONCE", There is only 2-3/8" travel max. on the PB handle when it's fully maxed out on the knob. This is sufficient if all the drum components are in good shape and the shoes are adjusted correctly. The whole system was marginal right off the assembly line and any deficiency in it at all would lead to inadequate operation.
Our cable kit and actuator would increase its reliability , especially when using drums but we found with centre discs and rear drums that it was possible to torsion bend the PB levers inside the drums at about 300 lbs. pull on them, thus causing them to bind and release poorly.
If everything is set properly about a inch travel will set the PB in the brake drum properly, therefore the handle travel is sufficient, the actuator is self limiting to the extent that we limited the travel to 2.0 inches and we rely on the handle to make up the rest of the required travel, the handle by this time is almost straight up and thus its mechanical advantage is extremely high , ie. the actuator does the first 80% of the job and you do the rest.
We run 125 psi on the actuator cylinder and 2 inches of travel, hope this answers your question and if it doesn't fully, give me a call at (519) 368-7129
Cheers.....Albert
Phil Swanson
I took my whole system off and threw it away long ago. Biggest problem was the parking brakes caused the brakes to drag because they never would release properly at all four wheels. I bought a set of chocks from Harbor Freight that lock the dual wheels and never needed anything else. They work like a champ and are simple, I like simple. Best of all, the brakes release and the wheels roll free. Park works great too. IMHO those stock brakes are not worth fixing, junk! They are in the same category as those old steel wheels. I have thought about a front disc brake with an emergency brake conversion. This could be done just like what's on many smaller FWD cars. Another great project for someone.
Phil Swanson
77GMCPB
Bill Brown
I very seriously considered buying the improved cable/pulley system from Albert at Harrington but held off because I thought I couldn't justify the expense.
Now that I've lost a wheel due to, I'm confident, overheating from a dragging parking brake I know that I should have justified the expense. The repair of my lost wheel incident will far exceed the cost of Albert's setup and I'll still have a crappy parking brake setup. Penny wise, pound foolish.
--
Bill Brown - '77 Buckeye Cruiser
Coshocton OH
cargu...@sbcglobal.net
Gene Dotson
carguy wrote on Sun, 15 November 2009 18:33
> I very seriously considered buying the improved cable/pulley system from Albert at Harrington but held off because I thought I couldn't justify the expense.
>
> Now that I've lost a wheel due to, I'm confident, overheating from a dragging parking brake I know that I should have justified the expense. The repair of my lost wheel incident will far exceed the cost of Albert's setup and I'll still have a crappy parking brake setup. Penny wise, pound foolish.
Bill,
You won't be sorry if you install Albert's parking brake system. It really works.
--
Gene Dotson
74 Canyonlands
www.bdub.net/Motorhome_Enhancements
New Windows and Aluminum Radiators
Les Burt
Do you have a cable set-up available for the disc brake conversions that use
the Eldorado rear caliper and mounting plate? How about a cable set-up that
will operate Eldorado rear calipers on all 4 wheels?
I couldn't find any info relating to a rear disc park brake that uses all 4
wheels. Everything I found indicated using only 2 rear wheels and that the
e-brake didn't hold very well. I'm hoping that running the eldo park brake
function on the 4 wheels will provide sufficient holding power to keep me
happy. I'm not looking for anything that exceeds the stock drum park brakes,
just something that comes close.
Les Burt
Montreal
-----Original Message-----
From: gmclist...@temp.gmcnet.org
[mailto:gmclist...@temp.gmcnet.org] On Behalf Of Albert&Sheila
Branscombe
Sent: November 15, 2009 12:57 PM
To: gmc...@temp.gmcnet.org
Subject: Re: [GMCnet] Trouble adjusting parking brake
rhusak
Hi Guy's..
Have any of you tried the "Line Lock" type of device to use as a park brake.. Mine don't work either..
Ron
--
76 Eleganza II
Conifer, CO
Les Burt
your hydraulic components are in less than perfect condition, there is the
possibility that the pressurized fluid can weep past the internal seals of
the master or the wheel cylinders, resulting in loss of wheel clamping.
Would you want to trust such a system? Murphy's law applies here in that the
system is most likely to fail when you need it the most! The way I see it,
if I need to use the park brake, it is because I need more security than the
transmission park position can provide. A hydraulic system just doesn't
provide me with the comfort zone I need. I also doubt that it could be
considered a DOT approved system that would pass a vehicle safety
inspection.
Les Burt
Montreal
-----Original Message-----
From: gmclist...@temp.gmcnet.org
[mailto:gmclist...@temp.gmcnet.org] On Behalf Of rhusak
Sent: November 15, 2009 9:15 PM
To: gmc...@temp.gmcnet.org
Subject: Re: [GMCnet] Trouble adjusting parking brake
Albert&Sheila Branscombe
Albert,
Do you have a cable set-up available for the disc brake conversions that use
the Eldorado rear caliper and mounting plate? How about a cable set-up that
will operate Eldorado rear calipers on all 4 wheels?
Hi Les,
We can fab ss conduit sheaths and ss core cables in any length you require. Due to the way in which the Eldorado calipers might be mounted ( ie. 9, 3 or 12 o'clock positions) we never know what configuration is required, each system has to be manufactured as a sole entity.
There are folks that have had some sucess with single axle Eldorado calipers , ss cables and a power actuator , BUT unless the Eldorado caliper is in excellent condition ( which few are) this approach would be costly . The largest problem with using 4 of them would be the total (X4) lever travel distance. Even with using our system in a 2:1 travel ratio, I don't know if the travel would be sufficient.
Walt Healey down in Ohio was working with Jim K. on such a 4 caliper setup but I don't know what the current progress is. We have had such poor results on our test bed with the Eldorado calipers that we've all but given up on them. One last "kick at the can" will be to attempt to modify them to eliminate the're inherent tendency to slip, ( ie. the lever to advance without increasing the clamp force) . One must remember that we're looking for a set of calipers that will hold the equivalent of a small / medium size dump truck.
Cheers.......Albert
Mr.erf ERFisher
I had to use it 3 - 4 times going to the Port Costa rally, really a
twisting hilly road. I had to get to get out of the GMC several times, and
the line lock, was just the trick. With the rear 4 disk brakes locked up,
there was no way the GMC was going to move. Very good feeling
http://gmcmotorhome.info/BRKLOCK.html
very dependable
not battery dependent
and very fast and automatic to use.
So install what ever DOT system you want and makes you happy.
but put in the line lock when you want to KNOW , that you are safely parked.
gene
--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
Larry
very dependable
not battery dependent
and very fast and automatic to use.
_________________________________________________________
I am not trying to go against any grain here but the blaring red light comes up with the Hydraulic system used as a Parking brake.
In my eyes, if your brake system ( hydraulic ) is not in pristine condition, which most the time they are, you may lose pressure in the system. As I understand the line lock operation, it secures the pressure of the hydraulics at the rear wheel pistons. All good unless that one time happens when you are on a hill and pressure should gradually fade, I don't want to see anyones GMC rolling by itself down the hill.
If you use the line lock, ALWAYS put a chock or some blocks of wood in front of the tires, just in case.
Similar thoughts about the air cylinder, however I would assume, the air cylinder is operating a lever that is pushed to a mechanical lock, similar to the GolfCart Lever in the coach by the driver.
The Linear Actuator, uses 12vdc, is just an electric air cylinder and would operate a similar lever, as a matter of fact, the air cyl and LinAct should be interchangeable with minimal adjustments.
The advantage of the LinAct would be if you lose 12vdc, it won't move and lose the park brake tension.
The bad think about the LinAct would be if you lose 12vdc and want to release the PBrake, it won't move and lose the park brake tension. This would have to be accomodated by a manual lever or release.
If there is anything that can wear or break down, think twice and cover for that rare opportunity or we might be hearing about another Darwin Award......
My thoughts
--
Gatsbys' CRUISER :d
74 GLACIER X, 260
455/APC/4 bagg'r(ver3)
Remflex Manifold gaskets
_______________________________________________
Purchased 08-18-04
_
Mr.erf ERFisher
I have read many stories about :
breaking the parking pin
stuck on a really steep grade and cannot get off of the brake to put blocks
behind the wheels.
master cyl going to the floor and not being able to stop
(the lock will collect pressure pulses - so can be used to get what brakes
you can and hold them)
no brakes when the engine stops (vacuum booster is good too)
*I am a belt and suspender guy*, this is the finest backup you can have, and
with all four wheels blocked, you can hold the GMC and the toad, on a
vertical hill (with disk brakes ;>)
If you have driven the GMC much, you will have had times when you had to
stop in an inappropriate location, and you wish you had something like this
so you could get out of the driver seat.
good luck
gene
--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
Ken Henderson
parking brake like mine. IMHO, it is a much better option:
1. The line lock works on one brake system, front or rear. My pneumatic
"pedal puller" supplied by a tiny 100 psi compressor works on both systems,
locking all 6 wheels.
2. The line lock is a static or inactive device: What you trap is what you
got. If a few drops of hydraulic fluid leak past a seal, the brakes
release. With my air brake, those few drops will still leak, but the pedal
will move down to replace them until brake pedal travel is reached. Since
BOTH hydraulic systems will have to leak down, the mathematical probability
of failure is greatly reduced.
3. While not qualified as an independent system, the air brake may be a
better emergency brake than any cable operated rear-wheel-only system --
flipping the PARK switch causes the application of more force to the brake
pedal than many drivers will be able to exert.
It's true that my tiny air compressor will run periodically and eventually
drain the battery. Thus far, I don't see that as a problem. With my "slap
it together and see if it works" plumbing, the compressor runs about every
30-40 minutes. I don't know for how long because by the time I hear it
start, it's already stopped, without allowing me time to start counting the
seconds. I think the battery will carry it for a month or more. It will
definitely carry it long enough for me to install chocks. :-)
Ken H.
On Fri, Nov 20, 2009 at 1:53 PM, Mr.erf ERFisher <mr.er...@gmail.com>wrote:
> my line lock is the last resort.
>
> I have read many stories about :
>
> breaking the parking pin
>
> stuck on a really steep grade and cannot get off of the brake to put blocks
> behind the wheels.
>
> master cyl going to the floor and not being able to stop
> (the lock will collect pressure pulses - so can be used to get what brakes
> you can and hold them)
>
> no brakes when the engine stops (vacuum booster is good too)
>
> *I am a belt and suspender guy*, this is the finest backup you can have,
> and
> with all four wheels blocked, you can hold the GMC and the toad, on a
> vertical hill (with disk brakes ;>)
>
> If you have driven the GMC much, you will have had times when you had to
> stop in an inappropriate location, and you wish you had something like this
> so you could get out of the driver seat.
>
>
> good luck
> gene
>
>
Rob Mueller
The problem with anything other than a cable mechanically actuated manual
emergency / parking brake is that it might not meet the requirements for
registering a vehicle in your state.
Rob Mueller
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426
Ken Henderson
day have something that at least acts like a mechanical parking brake. But
I won't give up my air parking brake since it does not interfere with
anything else.
Ken H.
--
Ken H.
Americus, GA
'76 X-Birchaven
www.gmcwipersetc.com
Roger Black
I don't know about it holding when used as a parking brake, but if
it's what you showed me, this truly would be an emergency brake. It
does stop the G slowly, but surely.
Roger Black
Burns, TN
77 Birchaven SB
Rob Mueller
You bring up a good point; one should verify that ADDING an electrical,
hydraulic, or pneumatic actuator that operates in parallel with the
mechanical system is acceptable to the vehicle inspection authorities as
well!
I had to have Double Trouble registered by my cousin in NJ last year when I
bought it or I would have had to get it to Texas within 4 weeks of
transferring the title from Mary Newhouse to me and Helen and I wanted to
take longer than that.
When I bought the coach it didn't have any emergency or parking brakes. It
had been converted to Caddy disks on the rear and the cables were never
hooked up because the rear calipers didn't have the levers in them. I had
Ken Frey convert the rears to drums and hook up cables to them.
The day before I took it for inspection I spent a couple hours adjusting the
brake shoes, brake cables, and brake lever to make it hold. At inspection
they tested it and it held good enough to pass. WHEW!
Regards,
Rob Mueller
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426
-----Original Message-----
From: gmclist...@temp.gmcnet.org
[mailto:gmclist...@temp.gmcnet.org] On Behalf Of Ken Henderson
Sent: Saturday, 21 November 2009 12:03 PM
To: gmc...@temp.gmcnet.org
Subject: Re: [GMCnet] Trouble adjusting parking brake
That's for sure. While we have no inspections in GA, I still intend to some
day have something that at least acts like a mechanical parking brake. But
I won't give up my air parking brake since it does not interfere with
anything else.
Ken H.
Dave King
From reading many posts on this Forum about the "E brake", I see that those who have converted to all disc on the rear some times have trouble getting an E brake solution. For those interested in pursuing a possible option, the Audi R8 road car appears to have separate calipers on the rear discs for the E brake. As these cars are still somewhat rare and Audi parts tend to be expensive I have no idea how feasible this is. Several people were looking at this set up on a friends R8 and had ideas where to use these parts.
DAVE KING
Carleton Douglas
--
Carleton Douglas
73 custom, by myself
Prescott, AZ
Matt Colie
More than a few vehicles (like Corvette) have a drum parking brake inside the read disks. Has anybody investigated that one?
It would seem to be an effective solution and nothing interferes with anything else.
Matt
--
Matt & Mary Colie
'73 Glacier 23 Chaumiere (say show-me-air)
SE Michigan
Mr.erf ERFisher
plate for the rear caliper that would hold a second caliper, or a mechanical
caliper.
I don't know if he followed that forward or not.
gene
the Audi R8 road car appears to have separate calipers on the rear discs
for the E brake. As these cars are still somewhat rare and Audi parts tend
to be expensive I have no idea how feasible this is.
--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
John Wright
to have mechanical parking brake attachment. The article itself is
for a VW brake upgrade/conversion, but for our purposes it show the
brake calipers. Just scroll down thru the pictures. As you look down
thru the picture it also appears that the VW caliper may also be
usable as a less expensive alternative.
<http://www.worldimpex.com//assets/partdocuments/DIY_Rear_310mm_R32-1.pdf
>
J.R. Wright
GMC GreatLaker
TZE Zone Restorations
77 Eleganza Custom (For Sale)
1975 Avion (Under Reconstruction)
Michigan
John Wright
Audi R8 units. Just as well, Audi stuff would be very expensive. I
should read further before posting.
J.R. Wright
> I have found a DIY that show the Audi R8 rear caliper and it appears
> to have mechanical parking brake attachment. The article itself is
> for a VW brake upgrade/conversion, but for our purposes it show the
> brake calipers. Just scroll down thru the pictures. As you look down
> thru the picture it also appears that the VW caliper may also be
> usable as a less expensive alternative.
>
> <http://www.worldimpex.com//assets/partdocuments/DIY_Rear_310mm_R32-1.pdf
>>
>
> http://tinyurl.com/yzfqu2g
>
> J.R. Wright
> GMC GreatLaker
> TZE Zone Restorations
> 77 Eleganza Custom (For Sale)
> 1975 Avion (Under Reconstruction)
> Michigan
Larry
For 1/2 or less the price of a line lock, you can put together an air parking brake like mine. IMHO, it is a much better option:
_____________________________________________________________
I have to admit Ken, when I put my Darwin comment up, I did not have your system in mind.
But do you still have use of the OEM parking brake also?
That would be a difference also.
--
Gatsbys' CRUISER :d
74 GLACIER X, 260
455/APC/4 bagg'r(ver3)
Remflex Manifold gaskets
_______________________________________________
Purchased 08-18-04
_
Larry
Double Trouble X snip X didn't have any emergency or parking brakes. It had been converted to Caddy disks on the rear and the cables were never hooked up because the rear calipers didn't have the levers in them. I had Ken Frey convert the rears to drums and hook up cables to them.
The day before I took it for inspection I spent a couple hours adjusting the brake shoes, brake cables, and brake lever to make it hold. At inspection they tested it and it held good enough to pass. WHEW!.
___________________________________________________________
LOL, I should not be laughing. I have to use blocks since the PO never repaired them and the cables pulled apart.
That's were inspections may have a safety benefit.
I am looking for a solution to my P Brake, errrr, or lack there of.
I get nervous when I read the GolfCart Lever in the coach is not very good for setting the brake. So that makes me wonder.
I like to keep thing OEM where ever possible.
I have pondered this and of all the great fixes out there, and obvious problems that might come with them ( call this the Darwin Effect ), I am pondering a solution.
The cable system will remain the same, my upgrade to the stainless system offered as soon as I save up the nickles.
But one pulley will be on a lever that will move to and fro by a linear Activator.
That lever will be positioned at a point that puts all the tension on the lever ( similar to the GolfCart lever in the coach ). Final push allows the tension of the cable to hold the brake tension ( This is to counter the Darwin Effect of breaking the device or losing air or power and allowing the lever to move back to ( Pbrake off ) position.
If the LinActivator ( or air piston ) cannot set the Pbrake tension, the GolfCart lever inside will be pulled and set tension as normally done.
That Darwin, his effects do change the world, eh wot??
--
Gatsbys' CRUISER :d
74 GLACIER X, 260
455/APC/4 bagg'r(ver3)
Remflex Manifold gaskets
_______________________________________________
Purchased 08-18-04
_
Ken Henderson
All my air parking brake does is pull the brake pedal down and hold it there
with air pressure. A chain from the pneumatic cylinder to the brake pedal
is the only connection to the brakes. So, yes, you still have the use of
the OEM parking brake system.
Ken H.
On Sat, Nov 21, 2009 at 4:48 PM, Larry <slawre...@yahoo.com> wrote:
>
>
> For 1/2 or less the price of a line lock, you can put together an air
> parking brake like mine. IMHO, it is a much better option:
> _____________________________________________________________
>
> I have to admit Ken, when I put my Darwin comment up, I did not have your
> system in mind.
>
> But do you still have use of the OEM parking brake also?
>
> That would be a difference also.
>
>
>
>
Jim Kanomata
Since you did a fine job on the Electric wiper kit, would you consider
doing one for the brake system as it makes sense to use the whole
brake system and not just the rear.
I like the belt and suspenders also.
--
Jim Kanomata
Applied/GMC, Fremont,CA
ji...@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
Ken Henderson
I'll have to think about that a while. I just threw mine together from
surplus parts I had on hand; I'll have to look into the availability & cost
of equivalent components. Don't hold your breath while you wait or we'll
wind up without an ornamental.
Ken H.,
On Sat, Nov 21, 2009 at 6:15 PM, Jim Kanomata <jimka...@gmail.com> wrote:
> Ken,
> Since you did a fine job on the Electric wiper kit, would you consider
> doing one for the brake system as it makes sense to use the whole
> brake system and not just the rear.
> I like the belt and suspenders also.
>
> On Sat, Nov 21, 2009 at 2:28 PM, Ken Henderson <ken0he...@gmail.com>
> wrote:
> > Larry,
> >
> > All my air parking brake does is pull the brake pedal down and hold it
> there
> > with air pressure. A chain from the pneumatic cylinder to the brake
> pedal
> > is the only connection to the brakes. So, yes, you still have the use of
> > the OEM parking brake system.
> >
> > Ken H.
>
Michael Lincoln
simple device, located inside the coach, that includes an air strut?
Sent from my iPhone
Ken Henderson
the pedal and the steering wheel. Might be a challenge to push a strong
enough strut down -- maybe put a crossbar on it for a double-arm press.
Before I installed the pedal puller, I used an air cylinder in such an
arrangement to press the brake pedal for one-man brake bleeding and for
static brake force tests. Not real good for the steering column and wheel,
but I'm still using the same ones.
Ken H.
On Sat, Nov 21, 2009 at 7:41 PM, Michael Lincoln <mlin...@gmail.com>wrote:
> Is it possible and effective to merely push and hold the pedal with a
> simple device, located inside the coach, that includes an air strut?
Rob Mueller
Would a linear electric actuator of some kind provide enough force to hold
the brake pedal?
Regards,
Rob Mueller
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426
-----Original Message-----
From: gmclist...@temp.gmcnet.org
[mailto:gmclist...@temp.gmcnet.org] On Behalf Of Ken Henderson
Sent: Sunday, 22 November 2009 11:58 AM
To: gmc...@temp.gmcnet.org
Subject: Re: [GMCnet] Trouble adjusting parking brake
I don't see why you couldn't construct a device using an air strut between
the pedal and the steering wheel. Might be a challenge to push a strong
enough strut down -- maybe put a crossbar on it for a double-arm press.
Before I installed the pedal puller, I used an air cylinder in such an
arrangement to press the brake pedal for one-man brake bleeding and for
static brake force tests. Not real good for the steering column and wheel,
but I'm still using the same ones.
Ken H.
Ken Henderson
off. A seat actuator would probably do. That's what Bobby Moore, and
others, used to pull the parking brake cable.
The problem with that approach is that it would not be self-compensating for
any hydraulic leakage. One would need something like a hydraulic line
pressure switch to control it for that feature.
Ken H.
On Sat, Nov 21, 2009 at 8:05 PM, Rob Mueller <robmu...@iinet.net.au>wrote:
> Ken,
>
> Would a linear electric actuator of some kind provide enough force to hold
> the brake pedal?
>
>
Rob Mueller
Good point!
I was thinking that you could wire it into the brake light switch somehow
but then realized that's a mechanical switch that is actuated by a "lever"
on the shaft that connects the brake pedal to the booster.
Rob
-----Original Message-----
From: gmclist...@temp.gmcnet.org
[mailto:gmclist...@temp.gmcnet.org] On Behalf Of Ken Henderson
Sent: Sunday, 22 November 2009 12:11 PM
To: gmc...@temp.gmcnet.org
Subject: Re: [GMCnet] Trouble adjusting parking brake
The problem with that approach is that it would not be self-compensating for
any hydraulic leakage. One would need something like a hydraulic line
pressure switch to control it for that feature.
Ken H.
Larry
I was thinking that you could wire it into the brake light switch somehow but then realized that's a mechanical switch that is actuated by a "lever" on the shaft that connects the brake pedal to the booster.
_______________________________________________________
Perhaps the LinAct could compress a strut against the pedal, thus, maintaining pressure against the pedal should the pedal go down a bit.
you guys are so smart.
--
Gatsbys' CRUISER :d
74 GLACIER X, 260
455/APC/4 bagg'r(ver3)
Remflex Manifold gaskets
_______________________________________________
Purchased 08-18-04
_
Ken Henderson
the gas strut the 4"-5" necessary, then the strut would, if necessary, push
the pedal all the way to the floor...
Now tell me how you're gonna put all that stuff together so it will be
usable?
Ken H.
On Sat, Nov 21, 2009 at 10:41 PM, Larry <slawre...@yahoo.com> wrote:
>
>
> I was thinking that you could wire it into the brake light switch somehow
> but then realized that's a mechanical switch that is actuated by a "lever"
> on the shaft that connects the brake pedal to the booster.
> _______________________________________________________
>
> Perhaps the LinAct could compress a strut against the pedal, thus,
> maintaining pressure against the pedal should the pedal go down a bit.
>
> you guys are so smart.
>
>
>
Rob Mueller
Rube Goldberg or W. Heath Robinson come to mind! ;-)
Rob
-----Original Message-----
From: gmclist...@temp.gmcnet.org
[mailto:gmclist...@temp.gmcnet.org] On Behalf Of Ken Henderson
Sent: Sunday, 22 November 2009 3:01 PM
To: gmc...@temp.gmcnet.org
Subject: Re: [GMCnet] Trouble adjusting parking brake
Now tell me how you're gonna put all that stuff together so it will be
usable?
Ken H.
_______________________________________________
Larry
Now tell me how you're gonna put all that stuff together so it will be usable?
____________________________________________________________
Oh, I like a challange!
But it seems simple, doesn't it?
The LinAct is fastened to the firewall, horizontally, parallel with the firewall and floor.
The LinAct would have a stroke of about 7", this movement pushing a cradle that has the strut body attached. physically the cradle and strut would be next to the LinAct, conserving space, and would move with the LinAct piston/gear.
The Strut end is attached to a cable, which attaches to a pulley (on the firewall) behind the brake pedal and is attached to the brake pedal ( similar to some toad brake systems ).
As the linAct strokes out, the cradle moves forward, causing the strut to pull the cable which pulls the brake pedal down to apply the brake.
As the brake pedal reaches a point where the brakes are applied, the strut rod will compress into the cylinder, (applying pressure or tension to the brakes), until the LinAct reaches its limit.
Should the brake pressure fade, the strut would continue to adjust as long as the strut has enough stroke to maintain the brake.
Release of the LinAct would release the cable, which would release the strut which would release the brake.
See simple, and you guys thought of it.
Pure Genious
:lol: :lol: :lol: :lol: :lol: :lol:
--
Gatsbys' CRUISER :d
74 GLACIER X, 260
455/APC/4 bagg'r(ver3)
Remflex Manifold gaskets
_______________________________________________
Purchased 08-18-04
_