[GMCnet] water heated by engine?

[michael]

my gmc has lines running from the engine down the sides. the PO told us that the engine heats up the water. how does this work exactly? will I still have access to cold water? anything I should be mindful about?
--
1977 Palm beach
Bham AL
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[Larry Nelson]

As you travel down the road, your engine water pump, besides sending coolant to your radiator, also sends the same coolant back to your water heater. There is a heat exchanger in your OEM water heater. Cool feature. Lucky you, mine are unhooked by the PO. They are going to get hooked back up sometime soon. That water is pretty hot, and I believe their is a restrictor in the line to moderate the heat transfer. Others will be smarter than me about this.
--
Springfield, MO
Ex GMC'er, then GM Busnut
now '77 Eleganza ARS WB0JOT

[Ken Burton]

He has it correct.

It works fine and is a great feature if you are on the road and then parked for the evening. The internal construction of the heat exchanged is nothing more than a couple wraps of tubing around hot water tank. Engine coolant is run through it and the heat is exchanged to the tank and the water inside. The water heater still have the ability to heat water either electrically or by propane. I love mine and if I did not have it I would be making an engine coolant heat a exchanger to put on it.


--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

[Thomas Phipps]

But watch the extended hoses very carefully. If one ruptures, you will lose coolant and an engine. Don't ask how I know, lost a brand new rebuilt engine.
Also, install cut-off valves very close to the block to be able to shut down water flow completely.
I'm actually thinking of removing the feature, as I dislike doing the same thing several times.
Tom, MS II
--
1975 GMC Avion, under forever re-construction
Vicksburg, MS. 3.7 miles from I-20

[Bill Brown]

And yes, since the lines only go to the hot water heater you will still have unheated (cool) water from your tank. There is a check valve in the3 system that prevents the hot water from backing up into your fresh water tank.

But, be sure to check the condition of the hoses between the engine and the hot water heater. They MUST be pliable with no cracks. Remember that to loose one of these hoses will be a serious leak for your engine coolant. Some GMCers have added shut-off valves in these hoses to keep the coolant from being lost in the unlikely event of a failure in the hot water heater hose system.
--
Bill Brown - '77 Buckeye Cruiser
Coshocton OH
cargu...@sbcglobal.net

[Keith V]

and remember, the water will be really hot aftera day of driving!

like 195 degrees! Smokin!
--
Keith
69 Vette
29 Dodge
75 Royale GMC

[Richard Andis]

In reality I think the liabilities outweigh the benefits with this setup. Essentially all you are going to get is maybe one shower once you get to where you're going and setup camp.

Luckily, the PO replaced my water heater with a gas fired setup.
--
"Vahalla" - 1977 GMC Royale,
"Walküre" - 1974 VW Thing

[Joe Kemenczky]

Many many guys on here love this feature.. but when I did my demo it all came out.. what i found was where the hose had burst behind the fridge and i had coolant everywhere. the hoses had been fixed but the mess was never cleaned up.


--
Joe Kemenczky
1975 Eleganza ll (Odie) 75,000 miles.
Working on complete restoration. In year 2 of a 3 year restoration.
Loving every minute!
Monroe, NC (East of Charlotte).

[Craig Lechowicz]

Richard,
Like a lot of these things, it sort of depends how you're going to use it, how useful it is. If your intent is to always be at a full-hookup campground, using all the hot or cold water you want isn't a big issue. But, if you are dry camping, you probably want to be using way less than one 6 gallon tank of hot water a day, or you'll go through all of your fresh water and black tank capacity in a hurry. There is a convenience aspect to it that is nice, in that as soon as you stop, you have hot water without waiting for the electric (if you have the original GMC one) hot water heater to get going. And once heated by engine or electric (for 20 minutes or so) the original GMC heater will pretty much get you through a whole day of hot water use.
--
Craig Lechowicz
'77 Kingsley, Waterford, MI

[Robert Mueller]

Michael,

I've read all the other emails on this subject and they've covered the subject pretty well.

Personally I like the feature and replaced the lines and installed two shutoff valves on them which are attached to the rear engine
bulkhead so I can shut it off if something were to go wrong with the system.

Keith mentioned the fact that the water WILL get HOT!

Avion's have the same feature as GMC's but they use an Atwood water heater.

The Atwood has a single copper loop (not a coil) inside to heat the water. Despite the fact that there is a restrictor in the
fitting at the back of the intake manifold that is a bit less than 5/16" it is possible for the engine cooling water to run the
temperature of the water in the heater above the pressure / temperature relief valve setting. Turning on the pump will cause water
to dump out the relief valve. It also happens if you connect to city water. The relief valve will spew water until the incoming
water reduces the temperature in the tank below the temperature relief valve setting.

Here's a link to a kit that is available to stop this from happening:

http://www.gmcmhphotos.com/photos/data/500/Atwood_heat_exchanger_valve.pdf

They were available from Cinnabar, however, I don't know if they still are.

Regards,
Rob M.
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426

[Ken Burton]

tphipps wrote on Sun, 17 February 2013 16:14

> But watch the extended hoses very carefully. If one ruptures, you will lose coolant and an engine. Don't ask how I know, lost a brand new rebuilt engine.
> Also, install cut-off valves very close to the block to be able to shut down water flow completely.
> I'm actually thinking of removing the feature, as I dislike doing the same thing several times.
> Tom, MS II

The exposure on breaking a hose is no different that on any other coolant hose. (Heater and radiator)

If they are 30 years old they are suspect and will possibly break.

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

[Kingsley Coach]

Ken

Good to see you made your escape! <VBG>

Try not to bring logic into this discussion...

Mike in NM

--
Michael Beaton
1977 Kingsley 26-11
1977 Eleganza II 26-3
Antigonish, NS

[Ken Burton]

Kingsley Coach wrote on Sun, 17 February 2013 18:40

> Ken
>
> Good to see you made your escape! <VBG>
>
> Try not to bring logic into this discussion...
>
> Mike in NM

Yes I got out of the in a little over 2 days. I got two of the three doctors to release me. When the 3rd one did not show by 5 PM, I left without his blessing. I have been slowly getting better and did go to see the 3rd doctor on Friday. He said come back in 2 weeks.

I have been out and about a few hours per day but not lifting anything heavy. I spent about 6 hours Friday evening doing upgrades and equipment swaps to the airport network. I probably have about 30 hours of work left there but there is no rush. I need to wait on part of it for a contractor to run 8 new cables.

I'm OK. I'm just slowly recuperating.

[Mickey Space Ship Shuttle]

you the dude - dude. you the dude. :-)

i was in jail in new zeland once and my cell mate was a sheep.

next time ask for a sheep. I am very upset the sheep never writes are anything. :-}

[Joe Kemenczky]

Not sure if we are ready to hear about you and your sheep... LOL

--
Joe Kemenczky
1975 Eleganza ll (Odie) 75,000 miles.
Working on complete restoration. In year 2 of a 3 year restoration.
Loving every minute!
Monroe, NC (East of Charlotte).

[Matt Colie]

Robert Mueller wrote on Sun, 17 February 2013 18:20

> Michael,
>
> I've read all the other emails on this subject and they've covered the subject pretty well.
>
> Personally I like the feature and replaced the lines and installed two shutoff valves on them which are attached to the rear engine
> bulkhead so I can shut it off if something were to go wrong with the system.
>
> Keith mentioned the fact that the water WILL get HOT!
>
> Avion's have the same feature as GMC's but they use an Atwood water heater.
>
> The Atwood has a single copper loop (not a coil) inside to heat the water. Despite the fact that there is a restrictor in the fitting at the back of the intake manifold that is a bit less than 5/16" it is possible for the engine cooling water to run the temperature of the water in the heater above the pressure / temperature relief valve setting. Turning on the pump will cause water to dump out the relief valve. It also happens if you connect to city water. The relief valve will spew water until the incoming water reduces the temperature in the tank below the temperature relief valve setting.
>
> Here's a link to a kit that is available to stop this from happening:
>
> http://www.gmcmhphotos.com/photos/data/500/Atwood_heat_exchanger_valve.pdf
>
> They were available from Cinnabar, however, I don't know if they still are.
>
> Regards,
> Rob M.

Rob,

That is something that should be looked into...
I don't need it because I am currently running a 160° thermostat (or maybe none at all, I still haven't checked.)

I have put this type heater in six different performance cruisers so far and the only thing they don't like is that they have to run the engine to get hot water or get along side with shorepower (hated even more).

Matt
--
Matt & Mary Colie
'73 Glacier 23 Chaumière (say show-me-air) Just about as stock as you will find
SE Michigan - Twixt A2 and Detroit

[brian]

I replaced my hoses. not that bad, it is nice to have hot water when setting up.

Inspect hose very closely, mine looked ok, no cracks or etc. I took a one foot piece or so off intake manifold and folded it in half. Instead of bending it broke. I had never seen rubber hose do this.
--
brian
asheboro, nc
75 eleganza 2 74 build
118k miles and counting,
DOG HOUSE

[Jerry Wheeler]

I removed my hoses and installed an on-demand propane water heater. I
have instant hot water and no hoses to worry about leaking radiator fluid;
removing the old water heater also left me with more inside storage room.
Best of both worlds...... JWID.

JR Wheeler 78 Royale NC/OR

[Keith V]

Ken Burton wrote on Sun, 17 February 2013 18:06

> The exposure on breaking a hose is no different that on any other coolant hose. (Heater and radiator)
>
> If they are 30 years old they are suspect and will possibly break.

well except you have something like 4 times the fottage with the hoses running to the water heater. Thats a lot of extra hose to fail.
also it is exposed and hanging in big loops along the side of the coach

--
Keith
69 Vette
29 Dodge
75 Royale GMC

[Robert Mueller]

Keith,

When I replaced them in Double Trouble I drilled small 1/4" holes in the vertical surface of the frame "C" channel about an inch
down from the horizontal surface and tie wrapped the hoses to the top inside of the frame. The same process was followed for the
fuel lines at the bottom of the "C" channel.

I am going to keep the feature on The Blue Streak but instead of rubber hose I'll investigate the feasibility of using the same
plastic tubing that is used in houses for hot water.

Regards,
Rob M.
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426
 
-----Original Message-----

From: Keith V

well except you have something like 4 times the fottage with the hoses running to the water heater. Thats a lot of extra hose to
fail.
also it is exposed and hanging in big loops along the side of the coach
--
Keith

[Richard Andis]

Robert Mueller wrote on Mon, 18 February 2013 20:45

> I am going to keep the feature on The Blue Streak but instead of rubber hose I'll investigate the feasibility of using the same
> plastic tubing that is used in houses for hot water.

I believe MAX temp for PEX tubing is somewhere around 200 degrees. Fitting connections will be the first to go.

--
"Vahalla" - 1977 GMC Royale,
"Walküre" - 1974 VW Thing

[Ken Burton]

Robert Mueller wrote on Mon, 18 February 2013 20:45
>  

> -----Original Message-----
> From: Keith V
>
> well except you have something like 4 times the fottage with the hoses running to the water heater. Thats a lot of extra hose to
> fail.
> also it is exposed and hanging in big loops along the side of the coach
> --
> Keith

If I used that length rational, then I would be disconnecting the rear brakes because they have 4 times the length of the line running to the front wheels. They also at least 100 times the pressure of a coolant line.

The same could be said for the rear gas tank and lines.,

How about water lines lines running forward from the rear mounted water tank. After all, the sink lines run as high at 50 PSI where the coolant lines run a maximum of 9 PSI.

If the length rational were used on everything we would not have much working in our coach. On later coaches the rear house batteries are charged by an alternator driven off of the engine. Should I also eliminate that?

If someone is that paranoid they can always install a pressure sensor on the cooling system and monitor it along with everything else they have to watch while driving, like the road.

If the lines are very old replace them and be done with it.

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

[Craig Lechowicz]

Rob,
This monster 5/8" x 25' of aluminum fuel line from Summit might be a way to go for the water heater, with short pieces of rubber hoses at the end. Can you tell I'm getting tired of replacing boatloads of rubber hose on my coach for the 2nd time.

<http://www.summitracing.com/parts/sum-g2558/overview/>

--
Craig Lechowicz
'77 Kingsley, Waterford, MI

[Robert Mueller]

Richard,

I did a quick Google search "PEX tubing max temperature" and you're right. Investigation completed!

Thanks to you that was quick! ;-)

Regards,
Rob M.
Sydney, Australia

-----Original Message-----
From: Richard Andis

I believe MAX temp for PEX tubing is somewhere around 200 degrees. Fitting connections will be the first to go.

[Robert Mueller]

Craig,

Thanks, that has possibilities since it is aluminum (read light weight) I could buy it and bring it back as luggage. I'll see if
something similar is available here.

The fact that it is aluminum would also help overheating the water heater as it would radiate the full length from the engine to the
water heater. Now I'll have to figger out the downside of that happening!

Bloody hell, NOTHINGS simple!

Hmmmm, maybe KenB's right. ;-)

Regards,
Rob M.
Sydney, Australia
 

-----Original Message-----

From: Craig Lechowicz

Rob,
This monster 5/8" x 25' of aluminum fuel line from Summit might be a way to go for the water heater, with short pieces of rubber
hoses at the end. Can you tell I'm getting tired of replacing boatloads of rubber hose on my coach for the 2nd time.

<http://www.summitracing.com/parts/sum-g2558/overview/>
--
Craig

[Ken Burton]

Robert Mueller wrote on Tue, 19 February 2013 03:35

> Craig,
>
> Thanks, that has possibilities since it is aluminum (read light weight) I could buy it and bring it back as luggage. I'll see if
> something similar is available here.
>
> The fact that it is aluminum would also help overheating the water heater as it would radiate the full length from the engine to the
> water heater. Now I'll have to figger out the downside of that happening!
>
> Bloody hell, NOTHINGS simple!
>

> Hmmmm, maybe KenB's right. ;)

>
> Regards,
> Rob M.
> Sydney, Australia
>  
>
> -----Original Message-----
> From: Craig Lechowicz
>
> Rob,
> This monster 5/8" x 25' of aluminum fuel line from Summit might be a way to go for the water heater, with short pieces of rubber
> hoses at the end. Can you tell I'm getting tired of replacing boatloads of rubber hose on my coach for the 2nd time.
>
> <http://www.summitracing.com/parts/sum-g2558/overview/>
> --
> Craig
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

Why would you do such a ---- thing. What happens if a rock is kicked up and hits it. I once saw a copper propane line that was all beat up by rocks on a GMC. Granted is was in the pathe of the rear wheels. If you insist on using aluminum, cover it with some kind of hose or split loom tubing. Keep in mind aluminum corrodes from road salt. Aluminum and copper are not used for gas or brake lines. Steel would be the best choice after plain old heater hose.

I think you guys are making more of this than is necessary.

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

[Emery Stora]

I wonder how much heat you would lose due to the high thermo conduction of aluminum versus rubber. You might have to insulate the aluminum line to get any amount of useful heat back to the water heater.

Emery

[Johnny Bridges]

Depends on your use.  I like it - I have hot water for teh breakfast dishes next morning, even when I run the A/C or heat pump/heater all night.  My 30 amp electrics require a choice - A/C or water heater.
 
--johnny
'76 23' transmode norris'76 palm beach

[Matt Colie]

Keith V wrote on Mon, 18 February 2013 21:28

> well except you have something like 4 times the fottage with the hoses running to the water heater. Thats a lot of extra hose to fail.
> also it is exposed and hanging in big loops along the side of the coach

Keith,

If yours is hanging down in big loops, it was put in wrong.

Mine has OE clamps about every two feet and it tucked up against the coach floor between the frame rail and the rocker panel. For them to hit something there would also be major damage to the coach body and frame such that leaking coolant would not be a primary consideration. With most of the run outside of the engine room, the jacket is saved exposure to the external heat and fumes.

Matt
--
Matt & Mary Colie
'73 Glacier 23 Chaumière (say show-me-air) Just about as stock as you will find
SE Michigan - Twixt A2 and Detroit

[John R. Lebetski]

The sky is falling! There are still coaches running OE hoses back to the water heater. If you replace them correctly not chafing or hanging they will last a long long time. I would think fail point would be in the hot oily nasty flexing engine room on the supply line side first as Matt suggested. On the "what spares to carry" list would be enough heater hose to make a return shunt in the front or rear circuits. I think 3/4 will work on either size in a pinch.
--
John Lebetski
Chicago, IL
77 Eleganza II
Source America First

[Charles Boyd]

Rob: I would suggest using silicone engine water hoses. They are $$, but last forever. All the big truck uses them.




Robert Mueller wrote on Tue, 19 February 2013 04:35

> Craig,
>
> Thanks, that has possibilities since it is aluminum (read light weight) I could buy it and bring it back as luggage. I'll see if
> something similar is available here.
>
> The fact that it is aluminum would also help overheating the water heater as it would radiate the full length from the engine to the
> water heater. Now I'll have to figger out the downside of that happening!
>
> Bloody hell, NOTHINGS simple!
>

> Hmmmm, maybe KenB's right. ;)

>
> Regards,
> Rob M.
> Sydney, Australia
>  
>
> -----Original Message-----
> From: Craig Lechowicz
>
> Rob,
> This monster 5/8" x 25' of aluminum fuel line from Summit might be a way to go for the water heater, with short pieces of rubber
> hoses at the end. Can you tell I'm getting tired of replacing boatloads of rubber hose on my coach for the 2nd time.
>
> <http://www.summitracing.com/parts/sum-g2558/overview/>
> --
> Craig
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

--
C. Boyd
76 Crestmont
East Tennessee

[Gene Dotson]

JohnL455 wrote on Tue, 19 February 2013 10:17

> The sky is falling! There are still coaches running OE hoses back to the water heater. If you replace them correctly not chafing or hanging they will last a long long time. I would think fail point would be in the hot oily nasty flexing engine room on the supply line side first as Matt suggested. On the "what spares to carry" list would be enough heater hose to make a return shunt in the front or rear circuits. I think 3/4 will work on either size in a pinch.

John,

If there are any coaches still running with original hoses going to the bathroom water heater, they should be replaced immediately.
If they fail and you are not able to shut the engine down quickly, you run the probable risk of engine damage. It has happened more than once. The big problem is that you may not notice the engine temperature going up and then you are due for a major overhaul. This happened to a friend of mine and there was no place to pull off resulting in a new engine. We couldn't find where the engine coolant was being lost until we looked at the rear wheels and saw all the coolant there. It doesn't take long for the water heater to get up to temperature when plugged to electricity so I made up my mind then never to run the engine coolant back to the water heater.
--
Gene Dotson
74 Canyonlands
www.bdub.net/Motorhome_Enhancements New Windows and Aluminum Radiators

[Mickey Space Ship Shuttle]

what is the easiest way and affirmative way to plug these up until you decide to replace or take out. thank you mickey :-)


7 7palm beach

anaheim ca.

[Richard Andis]

mickeysss wrote on Tue, 19 February 2013 12:50
> what is the easiest way and affirmative way to plug these up until you decide to replace or take out. thank you mickey :)


I would think the shortest bypass loop closest to the engine would be best.

--
"Vahalla" - 1977 GMC Royale,
"Walküre" - 1974 VW Thing

[Carl Stouffer]

I personally like the engine water heat feature, and have taken advantage of it several times. One of the first things I did, when I bought the coach, was to replace all the heater hoses. I figure they will be good for about ten years from the time I did the replacement. I don't feel that those hoses are a liability at all if, like anything else, they are properly maintained. I DO look at them periodically to make sure they will not be an issue. The only rubber that I have not replaced on my coach is some of the propane hoses, the PS return hose, and the AC hoses, and I worry about them from time to time.
--
Carl S.
'75 ex Palm Beach
Tucson, AZ.

[Robert Mueller]

Chuck,

You DA MAN!

http://www.ebay.com/itm/5-8-ID-SILICONE-HEATER-HOSE-Blue-to-350-F-Sold-by-Foot-/290594642697

Regards,
Rob M.
Sydney, Australia

AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426
 

-----Original Message-----

From: Charles Boyd

Rob: I would suggest using silicone engine water hoses. They are $$, but last forever. All the big truck uses them.

C. Boyd

[D C _Mac_ Macdonald]

Hi, Rob and all!

At $3.50 per foot ($28) plus $2.50 shipping and
NO REQUIREMENT for effort by others, I would
say this is definitely the way to go!

Unless firm, no-cancel orders have gone in for
the Gates (?) hose, I'd recommend that everybody
buy his own stuff!

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
~~ ~ D C "Mac" Macdonald ~ ~~
~ ~ Amateur Radio - K2GKK ~ ~
~ ~ USAF and FAA, Retired ~ ~
~ ~ ~ Oklahoma City, OK ~ ~ ~
~~ ~ ~ "The Money Pit" ~ ~ ~~
~ ~ ~ ~ TZE166V101966 ~ ~ ~ ~
~ ~ ~ '76 ex-Palm Beach ~ ~ ~
~ www.gmcmhphotos.com/okclb ~
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
______________
*[ ]~~~[][ ][|\
*--OO--[]---O-*

> From: robmu...@iinet.net.au
> To: gmc...@temp.gmcnet.org
> Date: Wed, 20 Feb 2013 09:31:02 +1100
> Subject: Re: [GMCnet] water heated by engine?
>

[Emery Stora]

You are confusing me with the $28. If you are talking about the hose from the engine to the water heater isn't it going to require about 50 feet?

Emery Stora

[Dave Mumert]

Hi All

You could also try here
http://www.siliconeintakes.com

They also have Stainless steel flexible rad hoses, in a pretty blue color, I
think they may need silicone couplers on each end (also available in pretty
blue).

They also have silicone vacuum hoses, they appear to be limited to metric
sizes, I'm not sure if 8mm is an appropriate size.

Dave

> Subject: Re: [GMCnet] water heated by engine?

> http://www.ebay.com/itm/5-8-ID-SILICONE-HEATER-HOSE-Blue-to-350-F-
> Sold-by-Foot-/290594642697

[Matt Colie]

Emery Stora wrote on Tue, 19 February 2013 17:43

> You are confusing me with the $28. If you are talking about the hose from the engine to the water heater isn't it going to require about 50 feet?
>
> Emery Stora

As usual, Emery is correct here....
When I asked about this at Berrien Springs (mine were missing), someone said - Just buy the 50' box and it will just make it. - I guess he didn't know I had a 23. I had about 5' left over.

Matt
--
Matt & Mary Colie
'73 Glacier 23 Chaumière (say show-me-air) Just about as stock as you will find
SE Michigan - Twixt A2 and Detroit

[Charles Boyd]

Rob, you will need special clamps also, sae#10s, comes in boxes of 10.
http://www.goodyearep.com/ProductsDetail.aspx?id=16848




Robert Mueller wrote on Tue, 19 February 2013 17:30

--
C. Boyd
76 Crestmont
East Tennessee

[D C _Mac_ Macdonald]

I guess I got confused about which hose is being discussed
Folks are wanting 8 foot lengths. Was this for a hose going
to/from vapor canister?

I am now totally lost!

Mac in OKC
Money Pit


Sent from my iPhone

[Robert Mueller]

G'Day,

This deal got TOTALLY out of control with too many Monday Morning Quarterbacks so:

-----Original Message-----
From: Amazon.com [mailto:auto-comm...@amazon.com]
Sent: Wednesday, February 20, 2013 10:10 AM
To: Rob Mueller
Subject: Your e-mail to Midway Auto Supply

Here is a copy of the e-mail that you sent to Midway Auto Supply.

Order ID 111-4355347-7035418:
4 of Gates Rubber Company 27230 11/32 X 50 Vacuum Brake Hose [ASIN: B000CRHL58]

------------- Begin message -------------

Please cancel this order.

------------- End message -------------

Sorry

Regards,
Rob M.
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 D C _Mac_ Macdonald
Sent: Wednesday, February 20, 2013 11:56 AM
To: gmc...@temp.gmcnet.org
Subject: Re: [GMCnet] water heated by engine?

I guess I got confused about which hose is being discussed
Folks are wanting 8 foot lengths. Was this for a hose going
to/from vapor canister?

I am now totally lost!

Mac in OKC
Money Pit

[Mike Miller]

There a couple of different threads going on about hoses right now. (The on line forum helps to keep them straight... Until an email user's software splits the thread into two. :evil:

But THIS thread is about the hot water heater pre-heat (engine assist) hoses.

Chuck recommends "silicone engine water hoses" as they will last a LOT longer. (I agree.)

But I do want to mention that the rule of thumb of 50 foot to replace the hoses is for a "normal" GM upfitted curbside bath coach with the water heater under the shelf in the bathroom.

If your coach is anything else... you might need a different length. I would GUESS that a water heater in the bathroom on the roadside of a 26 foot coach (Like an Avion) would take more. But that would be a guess.

I know my 23 foot, Coachman upfitted, coaches with the water heater just aft of the entrance door (and that is just aft of the passenger seat) would take a LOT less hose.

Just thought I would throw that out there... :twisted:

k2gkk wrote on Tue, 19 February 2013 16:55

> I guess I got confused about which hose is being discussed
> Folks are wanting 8 foot lengths. Was this for a hose going
> to/from vapor canister?
>
> I am now totally lost!
>
> Mac in OKC
> Money Pit
>

> On Feb 19, 2013, at 16:44, "Emery Stora" <emery...@me.com> wrote:
>
>
> You are confusing me with the $28. If you are talking about the hose from the engine to the water heater isn't it going to require about 50 feet?
>
> Emery Stora
>
> On Feb 19, 2013, at 3:35 PM, D C _Mac_ Macdonald <k2...@hotmail.com> wrote:
>
> >
> > Hi, Rob and all!
> >
> > At $3.50 per foot ($28) plus $2.50 shipping and
> > NO REQUIREMENT for effort by others, I would
> > say this is definitely the way to go!
> >
> > Unless firm, no-cancel orders have gone in for
> > the Gates (?) hose, I'd recommend that everybody
> > buy his own stuff!
> >

> >> Subject: Re: [GMCnet] water heated by engine?
> >>
> >> Chuck,
> >>
> >> You DA MAN!
> >>
> >> http://www.ebay.com/itm/5-8-ID-SILICONE-HEATER-HOSE-Blue-to-350-F-Sold-by-Foot-/290594642697
> >>
> >> Regards,
> >> Rob M.
> >>

> >> -----Original Message-----
> >> From: Charles Boyd
> >>
> >> Rob: I would suggest using silicone engine water hoses. They are $$, but last forever. All the big truck uses them.
> >>
> >> C. Boyd

--
Mike Miller -- Hillsboro, OR -- on the Black list
(#1)'73 26' exPainted D. -- (#2)`78 23' Birchaven Rear Bath -- (#3)`77 23' Birchaven Side Bath
http://m000035.blogspot.com

[Robert Mueller]

Mike,

The water heater in an Avion is located under the bed on the passenger side next to the rear wheel well.

http://www.gmcmhphotos.com/photos/xantrex-inverter-install/p31265-xantrex-sw-2000-instal.html

Regards,
Rob M.
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426
 
-----Original Message-----

From: Mike Miller

There a couple of different threads going on about hoses right now. (The on line forum helps to keep them straight... Until an
email user's software splits the thread into two. :evil:

But THIS thread is about the hot water heater pre-heat (engine assist) hoses.

Chuck recommends "silicone engine water hoses" as they will last a LOT longer. (I agree.)

But I do want to mention that the rule of thumb of 50 foot to replace the hoses is for a "normal" GM upfitted curbside bath coach
with the water heater under the shelf in the bathroom.

If your coach is anything else... you might need a different length. I would GUESS that a water heater in the bathroom on the
roadside of a 26 foot coach (Like an Avion) would take more. But that would be a guess.

I know my 23 foot, Coachman upfitted, coaches with the water heater just aft of the entrance door (and that is just aft of the
passenger seat) would take a LOT less hose.

Just thought I would throw that out there... :twisted:

--
Mike

[Ken Henderson]

Mike,

I agree with you that a Birchaven will need a lot less hose to reach the
water heater, but since it's been 14+ years since I replaced mine, I don't
know how much it does take. Do you, being much more current (and probably
less CRS'd) know? I should probably replace mine now, or do the instant
water heater thing, while I'm still able.

Ken H.

On Tue, Feb 19, 2013 at 8:18 PM, Mike Miller wrote:

> ...

> I know my 23 foot, Coachman upfitted, coaches with the water heater just
> aft of the entrance door (and that is just aft of the passenger seat) would
> take a LOT less hose.
>

[Mickey Space Ship Shuttle]

HOT WATER HOSE REPLACEMENT

How many feet of what sizes of hose do I need to to a complete >replacement?Larry

50 feet. 51 if you also replace the hose on the pop off valve on
the water heater.Arch

Hose is 5/8 " ID --Emery Bill Brown - 77 Buckeye Cruiser

Coshocton, Ohio

http://gmcmotorhome.info/living.html#hose

I need to replace these hoses soon some time. THe blue hose is best for it? Any just as good that is cheaper?

http://www.ebay.com/itm/5-8-ID-SILICONE-HEATER-HOSE-Blue-to-350-F-Sold-by-Foot-/290594642697

This hose is $3.50 a foot times 51 feet. $178.50

any better way cheaper to do this?

[r...@gmcnet.org]

Ken Henderson wrote on Tue, 19 February 2013 18:25

> Mike,
>
> I agree with you that a Birchaven will need a lot less hose to reach the
> water heater, but since it's been 14+ years since I replaced mine, I don't
> know how much it does take. Do you, being much more current (and probably
> less CRS'd) know? I should probably replace mine now, or do the instant
> water heater thing, while I'm still able.
>
> Ken H.

Yep you screwed up Ken you should have done it with copper inside armor flex when copper was cheap now you get to do it again and then hopefully another time with a little help .
--
Roy Keen
Minden,NV
76 X Glenbrook

[Keith V]

Ken Burton wrote on Mon, 18 February 2013 21:23
> Robert Mueller wrote on Mon, 18 February 2013 20:45
> >  
> > -----Original Message-----
> > From: Keith V
> >
> > well except you have something like 4 times the footage with the hoses running to the water heater. Thats a lot of extra hose to

> > fail.
> > also it is exposed and hanging in big loops along the side of the coach

> > --
> > Keith
>
> If I used that length rational, then I would be disconnecting the rear brakes because they have 4 times the length of the line running to the front wheels. They also at least 100 times the pressure of a coolant line.
>
> The same could be said for the rear gas tank and lines.,
>
> How about water lines lines running forward from the rear mounted water tank. After all, the sink lines run as high at 50 PSI where the coolant lines run a maximum of 9 PSI.
>
> If the length rational were used on everything we would not have much working in our coach. On later coaches the rear house batteries are charged by an alternator driven off of the engine. Should I also eliminate that?
>
> If someone is that paranoid they can always install a pressure sensor on the cooling system and monitor it along with everything else they have to watch while driving, like the road.
>
> If the lines are very old replace them and be done with it.


Ken those aer terrible analogies and completely out of context.
--
Keith
69 Vette
29 Dodge
75 Royale GMC

[Mike Miller]

Ken Henderson wrote on Tue, 19 February 2013 18:25

> Mike,
>
> I agree with you that a Birchaven will need a lot less hose to reach the
> water heater, but since it's been 14+ years since I replaced mine, I don't
> know how much it does take. Do you, being much more current (and probably

> less CRS'd) know? ...


I haven't changed the hoses. I should do it on the rear bath but haven't.

It'll be quite some time before the other coach is at that point in the rebuild.

--
Mike Miller -- Hillsboro, OR -- on the Black list
(#1)'73 26' exPainted D. -- (#2)`78 23' Birchaven Rear Bath -- (#3)`77 23' Birchaven Side Bath
http://m000035.blogspot.com

[Ken Burton]

Keith V wrote on Wed, 20 February 2013 16:16

> Ken Burton wrote on Mon, 18 February 2013 21:23
> > Robert Mueller wrote on Mon, 18 February 2013 20:45
> > >  
> > > -----Original Message-----
> > > From: Keith V
> > >
> > > well except you have something like 4 times the footage with the hoses running to the water heater. Thats a lot of extra hose to
> > > fail.
> > > also it is exposed and hanging in big loops along the side of the coach
> > > --
> > > Keith
> >
> > If I used that length rational, then I would be disconnecting the rear brakes because they have 4 times the length of the line running to the front wheels. They also at least 100 times the pressure of a coolant line.
> >
> > The same could be said for the rear gas tank and lines.,
> >
> > How about water lines lines running forward from the rear mounted water tank. After all, the sink lines run as high at 50 PSI where the coolant lines run a maximum of 9 PSI.
> >
> > If the length rational were used on everything we would not have much working in our coach. On later coaches the rear house batteries are charged by an alternator driven off of the engine. Should I also eliminate that?
> >
> > If someone is that paranoid they can always install a pressure sensor on the cooling system and monitor it along with everything else they have to watch while driving, like the road.
> >
> > If the lines are very old replace them and be done with it.
>
>
> Ken those aer terrible analogies and completely out of context.

If you say so.

My point was that it is not the distance of the line but rather the condition of line that counts. If the line is 30 years old replace ALL heater hoses NOT just the ones to the water heater. BTW, those old hoses almost always fail at the clamping points (connections).

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

[Joe Crutchfield]

While we are on this subject, may I ask how to disconnect all those hoses. I have replaced my engine heated water heater with an lp/110v and want to remove all the hoses and plug all the holes in the back of the engine. I looked at this today and I have hoses going everywhere with "Y"s at the front and back of the engine. I assume (Ooops, shouldn't do that) that I only need a hose running from the water pump to the heater core and one from the heater core to the front of the engine. Can it be that simple?

Maybe there is a diagrahm somewhere but I have not been able to find it.

Thanks
--
Joe Crutchfield,
Watertown, TN,
77 Royale by Coachman, Rear Bath, 455, 3.07,

"Strangers are just friends I haven't met yet" - Will Rogers.

[Dennis Sexton]

JoeC wrote on Sat, 23 February 2013 21:56

> While we are on this subject, may I ask how to disconnect all those hoses. I have replaced my engine heated water heater with an lp/110v and want to remove all the hoses and plug all the holes in the back of the engine. I looked at this today and I have hoses going everywhere with "Y"s at the front and back of the engine. I assume (Ooops, shouldn't do that) that I only need a hose running from the water pump to the heater core and one from the heater core to the front of the engine. Can it be that simple?
>

> Maybe there is a diagram somewhere but I have not been able to find it.
>
> Thanks


Joe,

... my 73 did not come with the engine preheat for the water heater. There is a 3/4 inch hose from the heater core to the water pump. There is a 5/8 inch hose from the right rear of the engine intake manifold to the heater core and in that line I have installed a replacement cut off valve, vacuum operated.

http://www.gmcmhphotos.com/photos/73-painted-desert-230/p30899-gmc-motorhome-009.html

Looking down on the engine -- the 5/8 inch hose is in the bottom right of this photo.

http://www.gmcmhphotos.com/photos/73-painted-desert-230/p30630-sept-04-09-012.html

You may want to consider installing manual cut off valves in both lines -- in case your heater core leaks. The valves can be found in auto supply houses -- the old guy at my Autozone called them ambulance heater shut-off valves.
Dennis
--
Dennis S
73 Painted Desert 230
Germantown, TN

[Dennis Sexton]

PS here is one example of a heater shut off valve...

http://www.oreillyauto.com/site/c/detail/MRY0/84707/02708.oap?year=1966&make=Chevrolet&model=C10%2BPickup&vi=1321861&ck=Search_02708_1321861_-1&pt=02708&ppt=C0331

[Joe Crutchfield]

Thanks Dennis. I am not sure I understand the heater control valve. Did you add it because your dash heater control did not work correctly? Is this a requirement for me to eliminate all the hoses to the water heater?

--
Joe Crutchfield,
Watertown, TN,
77 Royale by Coachman, Rear Bath, 455, 3.07,

"Strangers are just friends I haven't met yet" - Will Rogers.

[Ken Burton]

There are no holes to plug. The hose on the back of the intake manifold runs to the heater core and an second hose on the front (water pump) runs to the heater core. That is it.

One word of warning. There needs to be some coolant flow at all times to maintain proper engine coolant circulation. On the OEM installation, the vacuum controlled shut off valve has a hole in it and the butterfly inside does not fit tightly. This allows some coolant flow with the valve off. On a GMC is it OK to install a full shut off in the heater line because there is an alternate coolant path through the water heater. You are proposing to remove the alternate path so do NOT install a valve that completely shuts off the heater core path. Your engine will thank you.

Ken B.

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

[Joe Weir]

RockAuto has goodyear silicon hose for $3/ft sold in 50' boxes:

http://www.rockauto.com/catalog/raframecatalog.php?catalog=147&partnum=65041&a=FR147-65041-458172

http://www.rockauto.com/catalog/raframecatalog.php?catalog=147&partnum=65041&a=FR147-65041-458172

[Wally Anderson]

mickeysss wrote on Wed, 20 February 2013 10:15
> HOT WATER HOSE REPLACEMENT

>
>
> I need to replace these hoses soon some time. THe blue hose is best for it? Any just as good that is cheaper?
>
> http://www.ebay.com/itm/5-8-ID-SILICONE-HEATER-HOSE-Blue-to-350-F-Sold-by-Foot-/290594642697
>
> This hose is $3.50 a foot times 51 feet. $178.50
>
> any better way cheaper to do this?

I read that silicone coolant hose has a higher water permeation rate than conventional hose. Gates makes a green stripe hose with about the same life at a lower initial cost.
http://www.gates.com/brochure.cfm?brochure=925&location_id=1175
http://youtu.be/rSl0URba_ho

--
Wally Anderson
1975 Glenbrook
Megasquirt 455 port injection science project-On the road 16,468 miles
Omaha Nebraska
Greater Midwest Classics
GMCES
http://wallyandsue.blogspot.com/

[A.]

Ken Burton wrote on Sun, 24 February 2013 02:19

> There are no holes to plug. The hose on the back of the intake manifold runs to the heater core and an second hose on the front (water pump) runs to the heater core. That is it.
>

> One word of warning. There needs to be some coolant flow at all times to maintain proper engine coolant circulation. On the OEM installation, the vacuum controlled shut off valve has a hole in it and the butterfly inside does not fit tightly. This allows some coolant flow with the valve off. On a GMC it is OK to install a full shut off in the heater line because there is an alternate coolant path through the water heater. You are proposing to remove the alternate path so do NOT install a valve that completely shuts off the heater core path. Your engine will thank you.
>
> Ken B.
If the water heater has already been taken out of the equation, how do you completely shut off the flow to the heater coil while maintaining that flow through the engine?
It is way too hot here in the South to have the dash AC fighting with the heater core in the Summer.
--
'73 23' Sequoia For Camping
'73 23' CanyonLands For Sale
UA (Upper Alabama)
"Time is money. If you use YOUR time, you get to keep YOUR money."

[D C _Mac_ Macdonald]

Since my "plan" (desire?) is to totally remove the OEM
water heater and replace it with the AQUAH 6L "instant"
propane-fired heater and I seriously doubt that markbb1
has hotter summer temps than Oklahoma, the answer to his
question is rather important to me, also!

[:<)]

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
~~ ~ D C "Mac" Macdonald ~ ~~
~ ~ Amateur Radio - K2GKK ~ ~
~ ~ USAF and FAA, Retired ~ ~
~ ~ ~ Oklahoma City, OK ~ ~ ~
~~ ~ ~ "The Money Pit" ~ ~ ~~
~ ~ ~ ~ TZE166V101966 ~ ~ ~ ~
~ ~ ~ '76 ex-Palm Beach ~ ~ ~
~ www.gmcmhphotos.com/okclb ~
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
______________
*[ ]~~~[][ ][|\
*--OO--[]---O-*

> To: gmc...@temp.gmcnet.org
> From: mar...@netzero.com
> Date: Sun, 24 Feb 2013 14:53:22 -0600

> Subject: Re: [GMCnet] water heated by engine?
>
>
>

[Ken Burton]

If your water heater loop in still installed you have to do nothing. Otherwise you will install a bypass hose between the rear of the intake manifold and the water pump if you intend to shut off the heater. I saw a 455 APU once and that is what they had done with the heater hose loop. My JD tractor also came that way from the factory.

Another option is to install a bypass valve at the heater core up front. McMaster had one in 1/2" inch that I used on my John Deere which requires a similar coolant flow. I have heat in the winter and bypass in the summer. I haven't looked for one in 5/8" since I do not need it in my GMC. So lok in Mc Master for the 5/8" 2 way valve.

I love having free hot water whenever I stop for a short break or for the night.

I'm also thinking of adding a 2nd cabin heater in the rear attached to the same loop. Arch added a second cabin heater on his coach but it was under the passenger seat.

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

[Robert Mueller]

Wally,

The Gates ad is Interesting but as far as the water permeation problem goes I don't think we'll be driving our GMCs for two shifts a
day (16 hours?) for a year so I don't think we need to worry about water loss through permeation! ;-)

It is cheaper than the silicone and can be purchased from Rock Auto:

A) 5/8" ID under the part number 28441 in 50 foot lengths @ 1.81 per foot making $90.50

B) 3/4" ID under the part number 28442 in 50 foot lengths @ $2.33 per foot or $116.50

Here's a link to Rock Auto, if you want this hose just do a Part Number Search

http://www.rockauto.com/

Unfortunately it's black and won't color coordinate as well with Olds blue as the blue silicone will. ;-)

Regards,
Rob M.

-----Original Message-----

From: Wally Anderson

I read that silicone coolant hose has a higher water permeation rate than conventional hose. Gates makes a green stripe hose with
about the same life at a lower initial cost.
http://www.gates.com/brochure.cfm?brochure=925&location_id=1175
http://youtu.be/rSl0URba_ho

Wally

[Robert Mueller]

Ken,

I'm confused! The MM notes the following:

COOLING SYSTEM CIRCULATION (FIGURE 4)
The coolant is circulated by a centrifugal pump mounted on the front engine cover which forms the outlet side of the pump. The
engine fan and pulley(s) are bolted to the pump shaft hub at its forward end. Thus both the fan and pump are belt driven by a
crankshaft pulley bolted to the harmonic balancer. The pump shaft and bearing assembly is pressed in the water pump cover. The
bearings are permanently lubricated during manufacture and sealed to prevent loss of lubricant and entry of dirt. The pump is sealed
against coolant leakage by a packless non-adjustable seal assembly mounted in the pump in position to bear against the impeller hub.
The inlet pipe cast in the pump body feeds into the passage formed by the cover and the front face of the impeller, which is Figure
3-Coolant Recovery Reservoir, Type II mounted on the bearing shaft with the vanes facing forward. Coolant flows through the inlet
passage to the low pressure area at the center where it then flows radially through six openings in the impeller. Vanes on the
rotating impeller cause the coolant to flow rearward through two discharge passages cast in the engine block. These passages deliver
an equal quantity of coolant to each cylinder bank water jacket.

The coolant then flows rearward through the water jacket which surrounds each cylinder barrel and extends below the lower limit of
piston ring travel. After flowing the full length of the cylinder banks, the coolant flows up through openings to the rear of the
cylinder bank into the cylinder heads. The coolant flows forward in the cylinder heads to cool the combustion chamber areas.

Next, the coolant flows into the intake manifold water passage from the forward port of the cylinder heads to the thermostat housing
and thermostat by pass. A nipple in the pump body allows connection of the heater hose.

A pellet type thermostat housed in the forward (outlet) end of the intake manifold controls the circulation of water through the
engine radiator. During cold engine operation when the thermostat is closed, a thermostat by-pass, open at all times, allows
recirculation of coolant through the engine to provide rapid warm-up. When the thermostat opens, (195°F / 90.6°C.) coolant is
directed to the left tank of the radiator, through the radiator core and right tank to the water pump inlet where the cycle is
repeated.

It doesn’t mention flow through the water heater at all.

Regards,
Rob M.

-----Original Message-----

From: Ken Burton

If your water heater loop in still installed you have to do nothing. Otherwise you will install a bypass hose between the rear of
the intake manifold and the water pump if you intend to shut off the heater. I saw a 455 APU once and that is what they had done
with the heater hose loop. My JD tractor also came that way from the factory.

Another option is to install a bypass valve at the heater core up front. McMaster had one in 1/2" inch that I used on my John Deere
which requires a similar coolant flow. I have heat in the winter and bypass in the summer. I haven't looked for one in 5/8"
since I do not need it in my GMC. So lok in Mc Master for the 5/8" 2 way valve.

I love having free hot water whenever I stop for a short break or for the night.

I'm also thinking of adding a 2nd cabin heater in the rear attached to the same loop. Arch added a second cabin heater on his coach
but it was under the passenger seat.
--
Ken

[Matt Colie]

Referring to what Robert Mueller wrote on Sun, 24 February 2013 18:50

Rob,

Of course there is no mention of the water heater loop....
Transmodes didn't have it.

The real reason is that some intern level person in techpubs just copied that whole section out of a prior vehicle manual and nobody got off their dead ass to check it out. How do you think we ended up with the wrong firing order in one publication???

Matt
--
Matt & Mary Colie
'73 Glacier 23 Chaumière (say show-me-air) Just about as stock as you will find
SE Michigan - Twixt A2 and Detroit

[Ken Burton]

Robert Mueller wrote on Sun, 24 February 2013 17:25

> Wally,
>
> The Gates ad is Interesting but as far as the water permeation problem goes I don't think we'll be driving our GMCs for two shifts a

> day (16 hours?) for a year so I don't think we need to worry about water loss through permeation! ;)

>
> It is cheaper than the silicone and can be purchased from Rock Auto:
>
> A) 5/8" ID under the part number 28441 in 50 foot lengths @ 1.81 per foot making $90.50
>
> B) 3/4" ID under the part number 28442 in 50 foot lengths @ $2.33 per foot or $116.50
>
> Here's a link to Rock Auto, if you want this hose just do a Part Number Search
>
> http://www.rockauto.com/
>

> Unfortunately it's black and won't color coordinate as well with Olds blue as the blue silicone will. ;)
>
> Regards,
> Rob M.

I was hoping for orange or red.

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

[A.]

Matt Colie wrote on Sun, 24 February 2013 18:54

> Referring to what Robert Mueller wrote on Sun, 24 February 2013 18:50
>
> Rob,
>
> Of course there is no mention of the water heater loop....
> Transmodes didn't have it.
>
> The real reason is that some intern level person in techpubs just copied that whole section out of a prior vehicle manual and nobody got off their dead ass to check it out. How do you think we ended up with the wrong firing order in one publication???
>
> Matt

I think what Rob is asking is: "How could blocking off the water heater loop AND the cab heater core loop at the same time muck up the engine cooling if the cooling system works as described in that manual?"

--
'73 23' Sequoia For Camping
'73 23' CanyonLands For Sale
UA (Upper Alabama)
"Time is money. If you use YOUR time, you get to keep YOUR money."

[Robert Mueller]

Mark,

Exactly!

Thanks for clarifying that.

Regards,
Rob M.

-----Original Message-----

From: A.

I think what Rob is asking is: "How could blocking off the water heater loop AND the cab heater core loop at the same time muck up
the engine cooling if the cooling system works as described in that manual?"

[Ken Burton]

Coolant flow through the rear of the engine is through the rear cylinders, through the heads and into the intake manifold. You will notice that there is no connection for coolant flow between the rear and the front of the intake manifold. If you completely block the rear intake manifold port there is no way for the coolant from the rear cylinders, head, and manifold to circulate back to the water pump.

When these engines were used in the Toronado (it's primary purpose) there was no alternate path for this coolant flow through the house water heater. That is why the OEM heater control valve they used was not a complete shutoff. Like I said before the 455 I saw as an APU had no heater provision and had a bypass hose connected from the rear of the manifold to the front water pump.

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

[Ken Burton]

Here is the valve I think I used on my John Deere and also on my cold water storage tank in the GMC. I used 1/2" in both cases. You could use a 1/2" or 3/4" valve for the bypass somewhere in the heater core lines. Just screw in the appropriate size adapters directly into the valve.

http://www.mcmaster.com/#ball-valves/=lmivpb
Part number 4093T23
or
http://www.mcmaster.com/#ball-valves/=lmj1gt
Part Number 4374k53
Or if you really want to spend some money Mc Master-Carr has a stainless one for around $120.00

Ken Henderson posted an automotive on here on GMCnet a few months back. You might search the forum archives for it. I thinkit was somewhere around $15.00

Also do not forget to call Jim Kanomata. He tries to stock everything needed for a GMC. He might already have a 3-port valve solution for you.

[John Shotwell]

Matt Colie wrote on Sun, 24 February 2013 19:54

> Referring to what Robert Mueller wrote on Sun, 24 February 2013 18:50
>
> Rob,
>
> Of course there is no mention of the water heater loop....
> Transmodes didn't have it.
>
>

> Matt


Confused by this statement - I thought our '78 Royale was a transmode, and it did have the water heater loop. It was there because I took all of the hoses out when we put in the on demand propane unit. Just wondering...

shot
--
John Shotwell
Ridgeville Corners, OH
78 Royale Center Kitchen
Web Site: GMCmhRegistry.com /
Email: jo...@gmcmhregistry.com

[Mickey Space Ship Shuttle]

Mac you get the oscar tonight for art work with the type drawings. fantastic.

And the art oscar goes to D C "Mac" Macdonald. ~

[Robert Mueller]

Ken,

I'm going to respectfully disagree because of the following sentences in the MM:

The coolant then flows rearward through the water jacket which surrounds each cylinder barrel and extends below the lower limit of
piston ring travel.

After flowing the full length of the cylinder banks, the coolant flows up through openings to the rear of the cylinder bank into the
cylinder heads.

THE COOLANT FLOWS FORWARD IN THE CYLINDER HEADS TO COOL THE COMBUSTION CHAMBER AREAS.

NEXT, THE COOLANT FLOWS INTO THE INTAKE MANIFOLD WATER PASSAGE FROM THE FORWARD PORT OF THE CYLINDER HEADS TO THE THERMOSTAT HOUSING
AND THERMOSTAT BY PASS.

A nipple in the pump body allows connection of the heater hose.

I capitalized the two sentences which I believe support the argument that you can completely plug the heater hose connection and it
will have no effect real on engine coolant flow.

I'm going to drop this conversation for the moment, as you know I have the Paterson Olds engine in Houston which I will be
reassembling when I get back there. I am going to look at the water passages in the heads and see what that reveals.

Regards,
Rob M.

-----Original Message-----

From: Ken Burton

Coolant flow through the rear of the engine is through the rear cylinders, through the heads and into the intake manifold. You will
notice that there is no connection for coolant flow between the rear and the front of the intake manifold. If you completely block
the rear intake manifold port there is no way for the coolant from the rear cylinders, head, and manifold to circulate back to the
water pump.

When these engines were used in the Toronado (it's primary purpose) there was no alternate path for this coolant flow through the
house water heater. That is why the OEM heater control valve they used was not a complete shutoff. Like I said before the 455 I
saw as an APU had no heater provision and had a bypass hose connected from the rear of the manifold to the front water pump.
--
Ken

[Johnny Bridges]

Mine does.  Included by the upfitter (Norris) I assume?  
 
And, p'raps the attitude you mention below is one of the several reasons GM lost their position within the industry?
 
--johnny
'76 23' transmode norris
'76 palm beach

From: Matt Colie matt7...@gmail.com

Rob,

Of course there is no mention of the water heater loop....
Transmodes didn't have it. 

The real reason is that some intern level person in techpubs just copied that whole section out of a prior vehicle manual and nobody got off their dead ass to check it out.  How do you think we ended up with the wrong firing order in one publication???

Matt

[Ken Burton]

I'm too lazy to type. I'll call you.

Ken

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana