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Propane install from Hell [message #120591] Sat, 02 April 2011 15:19 Go to next message
Keith V is currently offline  Keith V   United States
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Registered: March 2008
Location: Mounds View,MN
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Well I've been chasing a propane leak for a while now, and found lots of issues. The installer clearly knew nothing about gas line plumbing and didn't want to learn.

Most of it was forgivable, but today I found something that puts me over the edge of tearing it all out and redoing it from scratch.

I found a Tee under the bed, in the hidden compartment. Remember I have storage under the bed, this is also where the battery charger is and there is a 110v socket and a 12v light.

If this connection leaks, it will fill the storage area with propane. and as my wife says, one little spark and we have a rocket propelled GMC!

Pictures...
http://www.gmcmhphotos.com/photos/showgallery.php?cat=5742


Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
Re: Propane install from Hell [message #120592 is a reply to message #120591] Sat, 02 April 2011 15:21 Go to previous messageGo to next message
Keith V is currently offline  Keith V   United States
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Registered: March 2008
Location: Mounds View,MN
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Oh I should mention that my plan is to redo all the lines so all connections are under the coach, except of course the connection to the CookTop and the furnace...

Any other suggestions for good propane instaliation?

Copper lines vs ??
Flare fittings vs??


Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
Re: Propane install from Hell [message #120594 is a reply to message #120592] Sat, 02 April 2011 16:04 Go to previous messageGo to next message
idrob is currently offline  idrob   United States
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Location: Central Idaho
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Keith V wrote on Sat, 02 April 2011 13:21

Oh I should mention that my plan is to redo all the lines so all connections are under the coach, except of course the connection to the CookTop and the furnace...

Any other suggestions for good propane instaliation?

Copper lines vs ??
Flare fittings vs??


I don't know of any alternative that is legal and safe to copper and flair fittings. They seem to work well for very long time periods, if done right. They have been used for many years in RV applications. In all the RV's I have had (close to 20) over the past 35 years, I have only had one serious issue, and that was a cracked flare nut but it was outside and under the belly pan of the Airstream trailer it was on. All Airstreams have always had their propane systems outside, under the belly skin with shutoff valves there, and single pipes leading up to each appliance, stove, refrigerator, furnace and hot water heater. On a motorhome, such as the GMC, if you re do the propane, be sure to stay away from heat sources such as the exhaust system, and also keep lines from where they might be hit with rubber pieces from a tire that comes apart. Look for good quality flare nuts, ones with longer necks are the best, but hard to come by. Invest in a good quality flair tool, and get the best flair nut wrenches made. I know snap on and craftsman are both good, but the inexpensive ones that I have tried are just worthless. They flex, and will neither tighten right nor take a flare nut off without flexing and damage. Once I got a set of good ones, and learned how much better they were than the inexpensive ones, I tossed the old in the trash and never looked back.




Rob Allen
former owner of '76 x-PB
Re: Propane install from Hell [message #120648 is a reply to message #120594] Sat, 02 April 2011 23:21 Go to previous messageGo to next message
Larry C   United States
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Registered: July 2004
Location: NE Illinois by the Illino...
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Senior Member
Is that OEM or PO OEM?? I don't know what the other manufacturers did, I have heard some talk about different ways things were done.

My 74 Glacier has the tank connected to the regulator, from there a rubber hose connects to a copper line.

The copper line travel goes through the wheel well, along the frame, to just in front of the tire to a "T", one goes up to the frig, the other travels across to the other side where it goes up to the furnace and stove.

My old SOB was all flex copper inside to the fixture. The frige had a small pipe in the frig compartment to attach to the frig but the connections were all metal.

The marine industry uses rubber hoses with gas fittings on them. If I replace the existing system, I have contemplated using the marine grade hose from outside to the appliance. need to be sure they will be protected from vibration and wear, but a GMC cant possibly compare to the pounding the waves give the bow of a boat.

There was only one installation that I wanted to get out of the coach when I found it. The PO had moved the propane tank under the bench seat for the kitch table. It was accessed from a door outside. But there were no vents for ventilation in the door or floor. My SOB had a propane tank attached to the frame and there was no floor beneath it, just road, plenty of ventilation but the road salts really ate it up.

Reason for venting...
Propane is heavy and falls down slowly. It likes to puddle in low spaces and accumulates in box areas very easily and if there is just a crack of space, it will travel through it and begin to puddle again. you obviously are aware of any spark setting it off.

just what I have


Gatsbys' CRUISER 08-18-04
74 GLACIER X, 260/455-APC-4 Bagg'r
Remflex Manifold gaskets
CampGrounds needed, Add yours to "PLACES" /> http://www.gmceast.com/travel
_
Re: Propane install from Hell [message #120679 is a reply to message #120648] Sun, 03 April 2011 10:34 Go to previous messageGo to next message
mike miller   United States
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Registered: February 2004
Location: Hillsboro, Oregon
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Senior Member
Larry C wrote on Sat, 02 April 2011 21:21

...
Reason for venting...
Propane is heavy and falls down slowly. It likes to puddle in low spaces and accumulates in box areas very easily and if there is just a crack of space, it will travel through it and begin to puddle again. you obviously are aware of any spark setting it off. ...


NOTE:

The original GM interiors where designed for an all electric refrigerator. The refer cabinet's floor was lower than the vented door. Some even have ac power plug-ins down in this area. Most conversions from electric to 2 or 3 way propane did not add any provision for venting. While it doesn't seem to be THAT much of a problem... a lot of coaches have been in use like this for some time... The POTENTIAL is there.

On my '73 xPainted D, I added a vent to the wheel-well and moved the plug-in up the side of the cabinet.


Mike Miller -- Hillsboro, OR -- on the Black list
(#2)`78 23' Birchaven Rear Bath -- (#3)`77 23' Birchaven Side Bath
More Sidekicks than GMC's and a late model Malibu called 'Boo' http://m000035.blogspot.com
Re: [GMCnet] Propane install from Hell [message #120681 is a reply to message #120648] Sun, 03 April 2011 10:33 Go to previous messageGo to next message
powerjon is currently offline  powerjon   United States
Messages: 2446
Registered: January 2004
Karma: 5
Senior Member

Of all the coaches that I have seen the description of the copper LP
tubing is probably factory installed. The 2 coaches that I have in
the shop now have copper tubing installed this way and they are
factory installed.

JR Wright

On Apr 3, 2011, at 12:21 AM, Larry wrote:

>
>
> Is that OEM or PO OEM?? I don't know what the other manufacturers
> did, I have heard some talk about different ways things were done.
>
> My 74 Glacier has the tank connected to the regulator, from there a
> rubber hose connects to a copper line.
>
> The copper line travel goes through the wheel well, along the
> frame, to just in front of the tire to a "T", one goes up to the
> frig, the other travels across to the other side where it goes up to
> the furnace and stove.
>
> My old SOB was all flex copper inside to the fixture. The frige had
> a small pipe in the frig compartment to attach to the frig but the
> connections were all metal.
>
> The marine industry uses rubber hoses with gas fittings on them. If
> I replace the existing system, I have contemplated using the marine
> grade hose from outside to the appliance. need to be sure they will
> be protected from vibration and wear, but a GMC cant possibly
> compare to the pounding the waves give the bow of a boat.
>
> There was only one installation that I wanted to get out of the
> coach when I found it. The PO had moved the propane tank under the
> bench seat for the kitch table. It was accessed from a door
> outside. But there were no vents for ventilation in the door or
> floor. My SOB had a propane tank attached to the frame and there
> was no floor beneath it, just road, plenty of ventilation but the
> road salts really ate it up.
>
> Reason for venting...
> Propane is heavy and falls down slowly. It likes to puddle in low
> spaces and accumulates in box areas very easily and if there is just
> a crack of space, it will travel through it and begin to puddle
> again. you obviously are aware of any spark setting it off.
>
> just what I have
> --
> Gatsbys' CRUISER :d
> 74 GLACIER X, 260
> 455/APC/4 bagg'r(ver3)
> Remflex Manifold gaskets
> _______________________________________________
> Purchased 08-18-04

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J.R. Wright
GMC GreatLaker
GMC Eastern States
GMCMI
78 30' Buskirk Stretch
75 Avion Under Reconstruction
Michigan
Re: [GMCnet] Propane install from Hell [message #120682 is a reply to message #120681] Sun, 03 April 2011 11:21 Go to previous messageGo to next message
Keith V is currently offline  Keith V   United States
Messages: 2337
Registered: March 2008
Location: Mounds View,MN
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Senior Member
The coach was redone on 2002 by Executive coaches in Indiana.
they did Excellent cabinetry work, but sucked at plumbing and propane installation.

Every flare connection had Teflon tape on the threads, the connections were impossible to even find without partial dis-assembly of the coach, and now the propane pool issue under the bed.

I will be redoing it with flexible copper lines running under the coach with protection from exhaust and vibration.

I just thought this was SO bad of an install that I had to share.

I just cannot imagine a worse place for a Tee than the one in the original message. Seriously, on a nice quiet calm night, a small leak fills the under bed compartment with propane...the battery charger..sparks, or someone plugs something into the outlet...
boom! Huge propane fire.


Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
Re: [GMCnet] Propane install from Hell [message #120722 is a reply to message #120682] Sun, 03 April 2011 19:29 Go to previous messageGo to next message
Larry C   United States
Messages: 1168
Registered: July 2004
Location: NE Illinois by the Illino...
Karma: 0
Senior Member
Every flare connection had Teflon tape on the threads,
______________________________

I had always thought that threads on flares should be untouched.

Recently I had the fuel pump on my old pick up replaced. the flare at the pump had corroded so bad that it would not come loose.

We tried to get a tight seal at the carb but it kept dripping. They put teflon on the threads and the flare sealed because the nut was MUCH easier to tighten. No teflon was on the sealed surface, just the threads for the nut.

Might be something to consider next time that nut is seemingly tight and the flare keeps dripping.


As for the propane puddling, yes it can do this, but you have to have a leak. That is why they sell propane detectors.

As I said, I am not aware if your coach was oem installed but different companies have different designs. I would prefer the propane lines all be outside.

Look at it this way, of all the vehicles that use propane, there does not seem to be much talk about exploding RV's.....

Propane is safe and I am comfortable with it. Remember too, the regulator brings that supply pressure down to a very low level and if it does leak, IT STINKS. YOU CAN'T MISS IT. IT STINKS!

for what its worth......


Gatsbys' CRUISER 08-18-04
74 GLACIER X, 260/455-APC-4 Bagg'r
Remflex Manifold gaskets
CampGrounds needed, Add yours to "PLACES" /> http://www.gmceast.com/travel
_
Re: [GMCnet] Propane install from Hell [message #120774 is a reply to message #120682] Mon, 04 April 2011 08:16 Go to previous message
Erv Troyer is currently offline  Erv Troyer   United States
Messages: 125
Registered: February 2004
Location: Lagrange, IN
Karma: 0
Senior Member
Keith V wrote on Sun, 03 April 2011 11:21

<snip>
Every flare connection had Teflon tape on the threads, the connections were impossible to even find without partial dis-assembly of the coach, and now the propane pool issue under the bed.

I will be redoing it with flexible copper lines running under the coach with protection from exhaust and vibration.


Every response on this thread has given good advice for you:

-Copper is good; make clean flares; no Teflon tape on flares
-NO CONNECTIONS in a floor cavity or closed compartment
-Fasten all lines to prevent vibration. Vibrating copper gets stiffer, then eventually breaks.

About all I can add is: Due to the extreme cost of copper many RV companies in this area are using 3/4" black iron pipe for the main run under the coach, attached to the frame, then branching off to each appliance with copper tubing.

Get a good grade of tubing (often called refrigeration grade) and not the cheaper grade used for water plumbing.

There are also flexible hoses approved for LP use in RV's. These come in various preassembled lengths and can be used for branch lines inside the RV. They sell lots of these in local RV surplus stores.

And save all the used copper you take out - scrap copper is selling for over $3 a pound now.


Erv Troyer Lagrange, IN
74 Sequoia
reo43@aol.com
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