[GMCnet] Onan Adventures
Carl Stouffer
that he wanted to get out of his garage. He explained that the generator came from Kerry Tandy's coach after he had been having trouble with it, and
had it replaced with a new one. Kerry, so the story goes, then pointed to the removed Onan and told them to "make that one like new" I got too good
of a deal on it to pass it up.
A couple of weeks ago, I decided it was time to do the swap, and drug the 'new' generator out of my garage for a test run. The night before, I had
pulled the spark plugs and sprayed a healthy dose of Sta-Bil Cylinder Fogger into the spark plug holes. Saturday morning, I rigged up a gas can, and
after correcting a mis-wired fuel pump, hooked it up to the coach batteries with jumper cables, and fired it up. It started almost immediately and
upon checking it out, I found that is was producing a nice steady 120 volts of AC power.
I then set about removing the old Onan, using an engine hoist, and although not an easy task, had it out in a few hours. I then worked on some
peripheral stuff (rebuilt the macerator, removed the batteries and Ragusa Battery tray, etc. and started re-lining the generator compartment with some
two pound foam/sound deadening insulation I had gotten from Jim Bounds. I finished that all up during the evenings of the next week and was ready to
stab the new generator into the hole on Memorial Day weekend.
I had it all ready to go in when my son arrived to help at about noon, and after removing a few more parts (the battery cable and fuel connection on
the bottom of the drawer) we had it bolted in. We then wired in the 12 volt starting cables and the 120 volt AC connections and tried to fire it up.
it would turn over very slowly, but not start. After checking the voltage draw on the starter, we decided there was something wrong with it and
pulled it off. The starter had evidently been wet and the brushes were rusted into the brush holder , so we put the starter from the old generator on
it. It then started okay, but still turned over somewhat slowly.
After checking the voltage and making a few small adjustments, I turned on both air conditioners. It handled them just fine, even after the
compressors kicked in. I then loaded it up with the water heater, and although we could tell there was a load on it, it handled that as well
(something that my old high hour unit could not do). The voltage and hertz never changed appreciably from the unloaded condition.
I worked on it some more on Sunday trying to wire in the remote panel. Covered under another thread, we had to make a few wiring corrections to the
control board and trace the wiring to the remote switch, but finally got it.
Next issue was the starter. Although the old Onan's starter was adequate to crank the tired old engine, it lacked the poewer to turn the new one over
at enough speed to start it. I took the water damaged starter to a local re-builder (sorry Jim K, the shipping would have killed me) and they turned
it into a work of art for $88.18. I thought 'if this thing works as well as it looks, it should start it with no problem'. I installed the rebuilt
starter and hit the switch and the generator fired off immediately on the first stroke.
I'm still working on a few details, which I hope to have finished up this weekend, but overall I am very pleased with the swap. Here's hoping it
works out well in the long run.
I guess the cost of a full recondition of this Onan wasn't a factor for Kerry, but I've often wondered why we don't see more of that going on. Are
the parts prohibitively expensive or just not available? The Power Drawer was specifically designed for the GMC and is therefore a perfect fit, so it
made sense to me, to stick with it. Besides, a new one costs ~$3500.00.
My old Onan, although a high hour machine (probably 0ver 3,000 hours, the Hobbs meter was broken when I got the coach) has always been dependable with
the only issues, ever, being fuel pump problems. It will be for sale if anyone needs one.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
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Jon Roche
other one?
I am trying to find time to de-carbon mine. No idea if it needs it, but that is about the last item to address on
My onan.
--
Jon Roche
75 palm beach
St. Cloud, MN
http://lqqkatjon.blogspot.com/
Carl Stouffer
> your other one?
>
>
> I am trying to find time to de-carbon mine. No idea if it needs it, but that is about the last item to address on
> My onan.
Also, the newer generator is not as noisy mechanically as the old one. My generator compartment is aluminum as well. Jim Bounds seemed surprised by
that, stating that most are plywood or fiberglass.
I had spent quite a bit of time replacing gaskets and seals and even adjusted the tappets on the old one, but it still made more noise from the valve
train, and maybe the bearings, than the new one.
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
Carl Stouffer
the parts prohibitively expensive or just not available? The Power Drawer was specifically designed for the GMC and is therefore a perfect fit, so it
made sense to me, to stick with it. Besides, a new one costs ~$3500.00"
Drawers. We spend big bucks on rebuilding engines (even conversions) and transmissions, why not the Onan?
gene Fisher
http://gmc49ers.blogspot.com/2015/09/onan-gmc-propane-conversion.html
Just run it
--
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
Matt Colie
run out without oil. Yes, parts are expansive, but go buy Honda parts.
Now, I have seen more than a few that were a slimy, nasty and miserable mess. I bought one for its value in scrap metal. Disassembled it and
resealed it with gasket goo and sold it.
The neighbor has one that he gave up on. It was in his lawn tractor. When he got the price for a rebuild kit, he found that he could buy a new
Kawasaki engine and an adapter kit for his tractor for less, but that is not a possibility for our application.
I'm going to keep changing the oil in mine. It does run even better with the right spark plugs. It did have the wrong number for years, but one
source gave a different number that I finally tried. It had the plugs for an NH in it.
Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Still Loving OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
Jim Miller
> I guess the cost of a full recondition of this Onan wasn't a factor for Kerry, but I've often wondered why we don't see more of that going on. Are the parts prohibitively expensive or just not available? The Power Drawer was specifically designed for the GMC and is therefore a perfect fit, so it made sense to me, to stick with it. Besides, a new one costs ~$3500.00.
I’ve worked on powerdrawers for almost 10 years now and I continue to marvel at the bad things people say about them and how frustrated owners can be - to the point of pulling out perfectly serviceable units and replacing them with some discontinued Honda or some other brand of 3600 RPM hack job. Granted, different users have different desires - some don’t care about noise, some don’t care about complexity and multiple failure modes - plus many on this list are more than capable of Macguyvering any machine to run in an emergency so a non-Onan is just perfect for them.
OTOH - the OEM Onan is a picture of simplicity - the prime mover is a rock solid, 8000 hour design that will last far longer than that with just basic care and perhaps a crank seal every couple of decades. The wasted-spark ignition system is dirt simple (what could be simpler than breaker point ignition?) and the fuel delivery and carburetion system is about the most trivial design possible. The starter is simple to work on and can be completely rebuilt by an amateur mechanic for less than $15 in parts. And that’s not to mention how much quieter it is at 1800RPM...
IMO the two things that every Onan should have done to it:
1. At a very minimum - immediately overhaul the breaker point ignition system and LEARN HOW IT WORKS. Better yet, replace it with Onan’s electronic ignition module. Best of all: Pertronix (but if you do a Pertronix, keep the breaker points in place as a backup and learn how to hook it back up - it is only one wire that needs reconnected). This latter hint saved my bacon on a trip one time when my pertronix mount broke off.
2. If you have an OEM control board then get rid of it and replace with a Dino. I’ve worked in the electronics design and testing business long enough to know that the OEM boards are on borrowed time and Murphy will fail yours when you need it most. If you can’t bring yourself to buy a Dino then buy two alligator clip leads and learn how to jumper battery+ to coil+ with one of them and then jog the starter with the other - the engine is more than capable of running without any control board in this manner.
The other observation I’ve made is that people panic when their onan acts up and they immediately start flailing around - hoping in desperation that they’ll find a solution by trying random things - jumping this pin to that, de-carboning heads, tearing into the carb before confirming that there’s enough fuel in their tanks, etc. The only way to solve Onan problems is methodically - a step at a time - by ruling out only a few potential problem sources.
The only other aspect of the Powerdrawer is the alternator section - of which most all problems can be solved. Just like the prime mover, the alternator is a dirt-simple design with only two semiconductor components in it - one of which is trivial to replace and other I’ve never seen go bad on any unit. The alternator, due to its simplicity - is FAR less likely to let you down than a system with a complex excitation and voltage regulation system.
—Jim
Jim Miller
1977 Eleganza
1977 Royale
Hamilton, OH
Carl Stouffer
I totally agree and have always thought that the Onan was a far superior unit compared to all other offerings. I guess the main issue for most people
is reliability which can be kind of sketchy if the machine has not been maintained correctly.
Again, the ONLY reason I replaced my old, high hour machine was that I got a great deal on this 'fully reconditioned' one. I hope it was the right
decision because it was a LOT of work.
One thing I had happen, that kind of puzzled me, was that under the initial testing, it would handle the load of both air conditioners and the water
heater, but yesterday, after running it for about half an hour, it would bog down when the second AC unit came in. The only difference was that I had
adjusted the carburetor a little richer. Upon further investigation, I found that it would handle the additional load if I leaned out the carb to the
point of 'lean best mixture'. What was happening is that the governor was opening the throttle and the engine was loading up instead of just taking
the load and then evening out again. Am I missing something, or did I just screw up the carb adjustment?
This new unit has an electric fuel pump that puts out 5 -9 PSI. Is that too much pressure? Could that be causing it to run a little rich? It also
has the Onan electronic ignition on it, and starts instantly.
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
Jim Miller
> I found that it would handle the additional load if I leaned out the carb to the point of 'lean best mixture'. What was happening is that the governor was opening the throttle and the engine was loading up instead of just taking the load and then evening out again. Am I missing something, or did I just screw up the carb adjustment?
I’d say you just had the carb off a little. Load it up to the max with both A/C compressors on and the electric hot water heater and then slowly adjust toward rich until it just starts to stumble - then back off perhaps 1/4 turn until it is stable. Then shut off an A/C and bring it back online 5 minutes later and see how the unit picks up the load when the compressor starts. After that test then unload the unit completely and then re-add load in increments to see how it acts.
IMO the carb adjustment isn’t too critical as long as it handles full load properly. Personally, I favor the adjustment toward rich rather than lean.
> This new unit has an electric fuel pump that puts out 5 -9 PSI. Is that too much pressure? Could that be causing it to run a little rich? It also has the Onan electronic ignition on it, and starts instantly.
I measured the OEM pumps at around 2 PSI and I think that is more than sufficient. 5-9 PSI is probably a little much - but if your machine acts OK and doesn’t have fuel pouring out the bowl vent then keep it!
—Jim
Jim Miller
1977 Eleganza
1977 Royale
Hamilton, OH
_______________________________________________
A.
> ...> This new unit has an electric fuel pump that puts out 5 -9 PSI. Is that too much pressure? Could that be causing it to run a little rich?
>
> I measured the OEM pumps at around 2 PSI and I think that is more than sufficient. 5-9 PSI is probably a little much - but if your machine acts OK
> and doesn't have fuel pouring out the bowl vent then keep it!
>
> Jim Miller
> 1977 Eleganza
> 1977 Royale
> Hamilton, OH
volume of the float.
If it ever gave me anything that resembled aggravation, I would be looking for a lower pressure pump.
--
73 23' CanyonLands Parts Unit 4 Sale
Upper Alabama
"Every day I become more convinced that I am the only person left on the planet that recognizes nonsense for what it is."
Carl Stouffer
>
> > I found that it would handle the additional load if I leaned out the carb to the point of 'lean best mixture'. What was happening is that
> > the governor was opening the throttle and the engine was loading up instead of just taking the load and then evening out again. Am I missing
> > something, or did I just screw up the carb adjustment?
>
> I'd say you just had the carb off a little. Load it up to the max with both A/C compressors on and the electric hot water heater and then slowly
> adjust toward rich until it just starts to stumble - then back off perhaps 1/4 turn until it is stable. Then shut off an A/C and bring it back
> online 5 minutes later and see how the unit picks up the load when the compressor starts. After that test then unload the unit completely and then
> re-add load in increments to see how it acts.
>
> IMO the carb adjustment isn't too critical as long as it handles full load properly. Personally, I favor the adjustment toward rich rather than
> lean.
>
> > This new unit has an electric fuel pump that puts out 5 -9 PSI. Is that too much pressure? Could that be causing it to run a little rich?
> > It also has the Onan electronic ignition on it, and starts instantly.
>
> I measured the OEM pumps at around 2 PSI and I think that is more than sufficient. 5-9 PSI is probably a little much - but if your machine acts OK
> and doesn't have fuel pouring out the bowl vent then keep it!
>
> Jim Miller
> 1977 Eleganza
> 1977 Royale
> Hamilton, OH
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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pouring out the fuel vent, so I guess it's OK. My old one has a low pressure Mr Gasket pump on it after the stock pump slowly failed. I think I'll
pick one of those up as a spare and if it acts up, I'll install the lower pressure one.
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
Richard Denney
Onans. There really are quite a lot of people who were more than systematic
in their attempts to make the Onan reliable, and still invested more time
in it than anything else on the coach only to find that it had simply
suffered too much neglect to ever work reliably.
I replaced mine before the oil leaking from the crank seals caught fire on
the muffler, or the exhaust jet from the crack in the exhaust manifold
charred all the way through the wood compartment (instead of just partway
through), or some other unknown problem appeared after spending the dollars
and hours to correct those problems. Bringing a high-hour, long-neglected
Onan up to a state of good repair so that it will be reliable is a hobby in
its own right--that wasn't my hobby and I didn't have time for it to be.
Forget trying to find anyone else who will actually repair it with
expertise and for a reasonable price rather than just throwing money at it
and letting me be the test facility.
Had I not had those issues, or had a 4K Onan that was really right been
reasonably available for a reasonable price, I might still be using an
Onan. But despite the one (frustrating, to be sure) issue I've had with the
Generac I installed, it's been reliable, and while I read about others
fighting strange issues with their Onans, I've been generating electricity.
I don't think removing the extra 250 pounds did the coach any harm, either.
But it certainly depends on the starting point.
I've had the Generac for a dozen years and it has all of about 130 hours on
it. 8000 hours of reliability isn't one of my requirements. :)
Rick "who didn't really want ten years of experience working on Power
Drawers" Denney
--
Rick Denney
73 x-Glacier 230 "Jaws"
Off-list email to rick at rickdenney dot com
jdli...@hotmail.com
Unfortunately the coach got hit before I was able to troubleshoot it.
--
JD Lisenby- USAF Ret
1978 Royale-455
Electromotive Tec2 FI & ignition
Navarre, FL
Carl Stouffer
would take, leading me to think it was overheating. I checked the timing and it was off quite a bit. As I moved the electronic pick-up one way, it
ran worse and the other way, better.
Got out the timing light and got it set to the 20 degrees BTC that it's supposed to be at, then re-set the governor speed and it ran 100% better and
handled all the load I could put on it. I also took the bowl off the bottom of the carburetor and cleaned a little bit of junk out of it and made
sure the jets were all clean. Crossing my fingers.
Hal Kading
With electronic ignition Ken B, IIRC, advises about 27 degrees advance for the best running Onan.
Hal Kading 78 Buskirk Las Cruces NM
Ken Burton
>
> With electronic ignition Ken B, IIRC, advises about 27 degrees advance for the best running Onan.
>
> Hal Kading 78 Buskirk Las Cruces NM
The original spec for the Onan with points was 25 BTDC. Onan had a few engines returned with detonation problems and so they reduced the spec to 22
BTDC. Then in another later move they changed the spec to 20 BTDC. Depending on when your flywheel was made, you can find any one of the 3 marks.
The problem was not with their timing spec. It was with the push rod operated points on it. That push rod system caused the static timing to jump
all over the place causing some situations where the timing advance was more than the engine could handle. So rather than fix the mechanical points
design problem, they took the cheap way out and simply reduced the timing spec.
When you replace the points with the Pertronix electronic pickup, you fix the mechanical points problem and the timing will remain stable wherever you
set it.
I talked to a retired Onan engineer about 12 years ago. He is the one that gave me the above history. He also stated if the timing was stable that
the Onan will easily run at 30 BTDC on 87 octane gas.
So I set mine at a conservative 26 - 27 BTDC. It has been this was for about 12 years with a Pertronix ignition installation.
Do not do set the timing above spec if you have one of the Onan solid state ignitions. That Onan system still uses the push rod and has the stability
problem.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Carl Stouffer
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
Ken Henderson
On the way to Alaska in 2000, I needed new points for my then-original
4kW. When I went to an RV dealership near Whidbey Island, WA, I found that
they were closing out their Onan inventory, which included an electronic
ignition kit. That cost little more than a set of points, so I bought and
installed it. What a difference! It really did run a LOT better.
Not too long after our return from Alaska, Lawrence Gaskins, a past GMCer
from WV, came up with the idea of using the Pertronix ignition triggered by
a magnet on the flywheel. Several of us, intrigued by the uniqueness of
the idea, possible only because of the distributorless lost-spark ignition
system, immediately followed Lawrence's lead. This album was first
published somewhat earlier than the photo site date indicates; Bobby Moore
wanted it as soon as he heard about it:
http://www.gmcmhphotos.com/photos/g3608-onan-ignition-upgrade-to-pertronix.html
One of the first things we noticed was that the timing mark with either of
the original ignition systems was a blur 1/4+" wide. On some Onans there
would be an occasional flash well outside that blur -- those ran very
badly. With Lawrence's mod installed, the timing mark was exactly the same
width with the engine running or not. That was enough to convince me that
the push rod operation of the OEM systems was introducing an erratic delay
in the timing function.
I, too, have talked to the GMCer (whose name I can't recall) mentioned by
Ken B., who was the Chief Engineer on the NH project. He agreed with our
hypothesis, and told me the same story he told Ken B. about the changes in
the timing spec.
So, keep an eye on that timing mark. If it starts to widen, at least clean
the bore where the push rod rides; changing the oil might help too. Better
yet, spend the few bucks and hour or so installing the Pertronix 1181 (same
as used for the Olds 455).
Ken H.
On Thu, Jun 8, 2017 at 9:19 AM, Carl Stouffer <carl...@gmail.com> wrote:
> Yeah, this one has the Onan solid state ignition, so I'll stick to the
> Onan spec. The timing mark looked to be pretty steady though.
> --
Carl Stouffer
maybe the way it was wired, burned out the pertronix unit immediately (two times). The experience cost me a fair amount of money and a lot of time,
and left me frustrated and disappointed. Probably just me being too dumb to make it work, but still the same result. I will just stick to the Onan
Solid State ignition system (for now at least).
I will double check the timing this weekend and call it good.
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
gene Fisher
--
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 Burton
timing has been rock solid. I had one go bad. The bolts that I mounted it with loosened up and the unit eventually hit the flywheel. I now install
them with nylon lock nuts or pop rivets.
I have one to install next week for Blaine. I'll do it the same way. 26-27 BTDC and either rivets or nylon lock nuts. I'll also add a ground wire
from the Pertronix mounting frame to the bolt holding the coil in place on the engine. Is it necessary? I do not know, but I wanted to assure that
it has a good path back to the engine ground rather than rely on the sheet metal path. It only takes a minute to add the additional wire. I also
cover the wires with an additional piece of shrink tubing to prevent any chafing.
Thanks to Lawrence Gaskins for a great idea and modification.
All of them I have installed have been 100% reliable.
When I did Dan Gregg's he had a Pertronix from a VW. It also worked just fine. I just had to make a different mounting bracket.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Matt Colie
> ,snip>
>
> All of them I have installed have been 100% reliable.
>
> When I did Dan Gregg's he had a Pertronix from a VW. It also worked just fine. I just had to make a different mounting bracket.
When I need to put one in an unlisted application, I look at all that are available cheap on E-bay and then look at the Pertronix picture book and
decide which will be easier to modify.
It always makes little engines run better.
I usually makes little flat head engines run and start better.
Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Still Loving OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
Ken Burton
with the magnet travel. Have you ever done one this way? If so, does it seem to work just as well? I have never tried it, but it sure would make
the mounting of the 1181 easier and I would not have to bend the 1181 bracket.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Johnny Bridges via Gmclist
but it broke and fell off (!). I told her send me some pictures and dimensions, and if it will fit, send the coach for a week and I'll stuff one of
the heathen chinee units in it. Or rehab the spare 6KW Onan power drawer and stuff it in.
--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
Jim Miller
> Matt, I have always modified the bracket so the magnet goes by perpendicular to the pickup unit. A week or so I saw a picture of one mounted inline with the magnet travel. Have you ever done one this way? If so, does it seem to work just as well? I have never tried it, but it sure would make the mounting of the 1181 easier and I would not have to bend the 1181 bracket.
My experience is that the 1181 mount is brittle - my original Pertronix installation attempt worked for a couple tens of hours and then failed when the pertronix’ aluminum bracket broke from fatigue due to wind buffeting from the flywheel airflow.
This is my original mounting arrangement that eventually failed (the last photo shows the failure):
Onan Pertronix Mount Mod I <http://www.jcmco.com/gallery/Pertronix>
And the second try that is still in service:
Onan Pertronix Mount - Mod II <http://www.jcmco.com/gallery/PertronixModII>
—Jim
Jim Miller
1977 Eleganza
1977 Royale
Hamilton, OH
_______________________________________________
Ken Burton
> On Jun 9, 2017, at 9:05 AM, Ken Burton wrote:
>
> Snip
> My experience is that the 1181 mount is brittle - my original Pertronix installation attempt worked for a couple tens of hours and then failed
> when the pertronix' aluminum bracket broke from fatigue due to wind buffeting from the flywheel airflow.
>
> This is my original mounting arrangement that eventually failed (the last photo shows the failure):
>
> Onan Pertronix Mount Mod I
>
>
> Onan Pertronix Mount - Mod II
>
> Jim Miller
> 1977 Eleganza
> 1977 Royale
> Hamilton, OH
Ken B.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Ken Henderson
Now I know why none of mine ever broke: They weren't fancy enough!!! Just
an angle bracket made of whatever was handy.
Beautiful work, even if the Pertronix wasn't up to the job in the first
attitude.
Ken H.
On Fri, Jun 9, 2017 at 11:45 AM, Jim Miller <gmc...@jcmco.com> wrote:
> On Jun 9, 2017, at 9:05 AM, Ken Burton <n9...@comcast.net> wrote:
>
> > Matt, I have always modified the bracket so the magnet goes by
> perpendicular to the pickup unit. A week or so I saw a picture of one
> mounted inline with the magnet travel. Have you ever done one this way?
> If so, does it seem to work just as well? I have never tried it, but it
> sure would make the mounting of the 1181 easier and I would not have to
> bend the 1181 bracket.
>
> My experience is that the 1181 mount is brittle - my original Pertronix
> installation attempt worked for a couple tens of hours and then failed when
> the pertronix’ aluminum bracket broke from fatigue due to wind buffeting
> from the flywheel airflow.
>
> This is my original mounting arrangement that eventually failed (the last
> photo shows the failure):
>
> Onan Pertronix Mount Mod I <http://www.jcmco.com/gallery/Pertronix>
>
> And the second try that is still in service:
>
> Onan Pertronix Mount - Mod II <http://www.jcmco.com/gallery/PertronixModII
> >
>
> —Jim
>
Jim Miller
> On Jun 9, 2017, at 5:01 PM, Ken Burton <n9...@comcast.net> wrote:
>
> Jim, the above pictures did not come through. Would you please try again or send me a URL via email to click on.
The one that failed:
http://www.jcmco.com/gallery/Pertronix
The one that has survived so far:
http://www.jcmco.com/gallery/PertronixModII
73, Jim N8ECI
Jim Miller
1977 Eleganza
1977 Royale
Hamilton, OH
Jim Miller
>
> Now I know why none of mine ever broke: They weren't fancy enough!!! Just an angle bracket made of whatever was handy.
>
> Beautiful work, even if the Pertronix wasn't up to the job in the first attitude.
Hi Ken,
Thank you for the compliment. My original Mod 0 mount was just a piece of angle bolted to the sheet metal behind the flywheel but after putting everything together I noticed that gently pushing on that sheet metal caused enough deflection that the flywheel would graze the pertronix; hence the reason for the bracket spanning two stronger bolt locations. Plus the bracket produced an awful whining sound due to the way the airflow went over it…
—Jim
Jim Miller
1977 Eleganza
1977 Royale
Hamilton, OH
_______________________________________________
Matt Colie
> inline with the magnet travel. Have you ever done one this way? If so, does it seem to work just as well? I have never tried it, but it sure
> would make the mounting of the 1181 easier and I would not have to bend the 1181 bracket.
I am back and the best I can tell you is that I always try to build it so the magnet passes much as it would in the installation. Past that, I can't
more much more specific. 1181 is not a number that I usually use. I gravitate towards those that set a magnet ring over the cam and so the face is
close and the mounting height is short. Just because of my avocation and education, I try to arrange the mounting to be out of the air flow.
Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Still Loving OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
Ken Burton
either orientation will work. I think I will try turning Blaine's 90 degrees from the others I have installed.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Ken Burton
Carl Stouffer
and I have the timing set at about 21 degrees advanced. You guys are right about the timing bouncing around a little bit, but it only appears to be a
degree in either direction. I'm going to call that good. The Onan is back to carrying the load of both air conditioners (original Duo-Therm units)
and the water heater without even complaining.
Thanks for all the help and advice on this. My son shouldn't have any problems with it on his trip to Colorado next week and my granddaughter should
be comfortable in the dinette with her mother going from front to rear.
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
Ken Burton
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
jdli...@hotmail.com
Jim,
That is a nice install!
Jim Miller wrote on Fri, 09 June 2017 17:08
> >
> > Jim, the above pictures did not come through. Would you please try again or send me a URL via email to click on.
>
> Hi Ken,
>
> The one that failed:
>
> http://www.jcmco.com/gallery/Pertronix
>
> The one that has survived so far:
>
> http://www.jcmco.com/gallery/PertronixModII
>
> 73, Jim N8ECI
>
> Jim Miller
> 1977 Eleganza
> 1977 Royale
> Hamilton, OH
>
>
>
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JD Lisenby- USAF Ret
1978 Royale-455
Electromotive Tec2 FI & ignition
Navarre, FL