Maiden Voyage and fuel line fail

There's gas comibng out where it shouldn't. This means the tanks gotta come down. As you put them back, configures the system the way you want.
Were I to do it again, I'd put metal lines down to the side of each tank.

--johnny
--
'76 23' transmode Norris upfit, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.

"Sometimes I wonder what tomorrow's gonna bring when I think about my dirty life and times" --Warren Zevon
 
Hello all-

So, back from our camping trip, and looking to get some things done on the coach. I've run the engine twice for about 15-20 minutes and no fuel
leaking to be found. I placed a container under the area where it was leaking and it's empty. I'm going to take it for a spin tomorrow to see if it
happens again.

so many projects!

--
1976 Palm Beach
Austin, TX
 
Adam, leaks do not cure themselves. You have a suspect fuel system. Rather than dick about patching ang guessing, become familiar with the
diagram(s), then drop the tanks, have a look to be sure they've no holes or rust through, replace >ALL< the lines, and cease wondering. It ain't that
hard physically, though it will take up the weekend. When you're done, everything will be in alcohol proof lines and now when it quits it ain't
because of a fuel leak or air sucing in a hole in a line:) Build it back box stock and then decide do you want one or more electric pumps, outboard
filters, etc. If you're a perfectionist (I'm not) get a couple of rolls of PolyArmour line, a crimping tool, and a tubing bender, and do the whole
thing in hardline. It willo outlast your children.

--johnny
--
'76 23' transmode Norris upfit, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.

"Sometimes I wonder what tomorrow's gonna bring when I think about my dirty life and times" --Warren Zevon
 
Adam,
Have you replaced ALL the 3/8 hoses?
Also the Fill hose connectors.
I'll be it will not leak again till you fill up. Also the O ring gasket at
the middle of the tank can leak when full.
If you have not replaced all the hoses and tubes, you must do it as the
ethanol is eating the old ones along with rubber in the tank selector
switch and fuel pump.

> Hello all-
>
> So, back from our camping trip, and looking to get some things done on the
> coach. I've run the engine twice for about 15-20 minutes and no fuel
> leaking to be found. I placed a container under the area where it was
> leaking and it's empty. I'm going to take it for a spin tomorrow to see if
> it
> happens again.
>
> so many projects!
>
>
> --
> 1976 Palm Beach
> Austin, TX
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
Listen to The Guru. He's correct.

--johnny
--
'76 23' transmode Norris upfit, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.

"Sometimes I wonder what tomorrow's gonna bring when I think about my dirty life and times" --Warren Zevon
 
Rubber fuel line is obsolete /non compatible with today's fuels. That said it is aged out many times over anyway. New rubber fuel line only lasts a
few years with ethanol E10 and breaks down. Only use fuel line such as Gates Barrier with the plasticized liner layer. It comes in low and high
pressure types and submersible type for those eith in tank pump applications. Fresh Barrier line should outlast all of us at this point.
--
John Lebetski
Woodstock, IL
77 Eleganza II
Source America First
 
> If I over filled the tanks, would it be possible for fuel to Come out of the top of the tank?
>
> Would it be possible to get fuel in the filler vent line?
>
> Fuel issues are no joke so we're grounded until I at least understand why it was happening.

IF everything is as it should be with your fuel system, I think it is virtually impossible to overfill the tanks.

By everything being as it should be, I mean:

1 - ALL hoses, including the filler hoses, are in good shape with tight clamps

2 - the sender O-ring seals are sound and not leaking

3 - the fuel/vapor separator in the left wheel well is working properly (this will keep raw fuel from getting to the carbon canister behind the right
front wheel)

From what I understand, Rob Mueller stores his coach with the fuel topped off to the point that he can see the gas at the filler neck, and doesn't
have any leakage.

I can fill my own coach to the top and not have any fuel leakage. Fuel leaking from the bottom of the coach is NOT normal. Do as others have
suggested and drop the tanks and replace all the rubber. IT is a lot of work, but not all that difficult.

--
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
 
I will get under the coach and poke around. I still have not identified the source of the open ended hose that the initial leak was coming from.

there is a hose with a bolt hose clamped into it, sealing it. there is another hose that open ended, that you can tell at one time had a hose clamp
on it. (where the initial leak was. This is the one I blocked, thinking it needed to be blocked, and had come undone on the road. Perhaps I caused
more pressure by blocking it, thereby causing the fuel to leak from another place? (the tank?)

both are mid way down the drivers side, right next to the fuel pump.

thanks again for your patience. and keep the answers and ideas (and firm suggestions that I trust you guys because you know what the hell you're
doing) coming.

:p


--
1976 Palm Beach
Austin, TX
 
>
> Perhaps I caused more pressure by blocking it, thereby causing the fuel to leak from another place? (the tank?)
> :p

Adam,

Very simply, that is just not possible if everything is as it should be.

I can fill my coach so I can see the fuel in the fill neck, and the only place it leaks now is from the carbon canister because the blasted vapor
valve is screwed up - AGAIN.

Matt
--
Matt & Mary Colie - Members GMCMI, GMCGL, GMCES
'73 Glacier 23 - Still Loving OE Rear Drum Brake with Applied Control Arms
Now with both true Keyless and remote entry
SE Michigan - Twixt A2 and Detroit
 
Adam,
You can spend time trying to FINGER out what is leaking, but you need to
understand that the old hoses must be replaced with the new type that can
survive the ethanal.
You will need to drop the tanks to rehose.
Any questions, call me.

On Thu, Oct 27, 2016 at 10:44 AM, Adam Metzger
wrote:

>
> I will get under the coach and poke around. I still have not identified
> the source of the open ended hose that the initial leak was coming from.
>
> there is a hose with a bolt hose clamped into it, sealing it. there is
> another hose that open ended, that you can tell at one time had a hose clamp
> on it. (where the initial leak was. This is the one I blocked, thinking
> it needed to be blocked, and had come undone on the road. Perhaps I caused
> more pressure by blocking it, thereby causing the fuel to leak from
> another place? (the tank?)
>
> both are mid way down the drivers side, right next to the fuel pump.
>
> thanks again for your patience. and keep the answers and ideas (and firm
> suggestions that I trust you guys because you know what the hell you're
> doing) coming.
>
> :p
>
>
> --
> 1976 Palm Beach
> Austin, TX
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
can someone remind me where I saw a list of fuel line lengths and sizes for a fuel line re-do?

Any other must haves?

--
1976 Palm Beach
Austin, TX
 
We have that data here we pass to people that call us.
3/8 hoes 22'
5/16 hose 33'
1/4 hose 11'
There are few other things I feel important to do at the same time to avoid
Vapor lock and also make fueling fast and easy. Just call and ask for me.

> can someone remind me where I saw a list of fuel line lengths and sizes
> for a fuel line re-do?
>
> Any other must haves?
>
>
> --
> 1976 Palm Beach
> Austin, TX
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
I've been under the coach trying to map out what the PO did so I can decide how to move forward.

I found out first that the line with the bolt in it, was about 18 inches long, and was open on the other end, connected to nothing. 8o

Some questions-

The connections on the bottom corner of each tank....these are what?
On my coach they are connected, including a t and a pump. The pump appears to run to the Onan.

There is a connection mounted to the driver side rail fore of the front wheels. Is this the selector switch?

Sorry for the seemingly dumb questions. There will be many more. :?

The diagrams in the manuals are no bueno.
--
1976 Palm Beach
Austin, TX
 
just forward of the rear wheels along the outside frame rail, was where the original selector switch was. Lots(included myself), install a pump
there as well, on the aux tank line. Usually close to that cross member. there should be a wire there that gets 12v when the fuel tank switch on
the dash is switched down to Aux.

OEM selector switch looks like this:
https://www.amazon.com/Standard-Motor-Products-FV1T-Selector/dp/B005ETOVZM/ref=sr_1_1?ie=UTF8&qid=1477927997&sr=8-1&keywords=fuel+selector+valve

Normally, the generator line runs from the top of the rear tank, to the generator, and the fuel pump for that is mounted on the side of the
generator. Those lines pop out about the rear wheel, and go toward the rear of the coach.

not going to guess as to anything else you might have going on.

--
Jon Roche
75 palm beach
St. Cloud, MN
http://lqqkatjon.blogspot.com/
 
Adam,
Pictures are worth a thousand works.

JR Wright

>
> I've been under the coach trying to map out what the PO did so I can decide how to move forward.
>
> I found out first that the line with the bolt in it, was about 18 inches long, and was open on the other end, connected to nothing. 8o
>
> Some questions-
>
> The connections on the bottom corner of each tank....these are what?
> On my coach they are connected, including a t and a pump. The pump appears to run to the Onan.
>
> There is a connection mounted to the driver side rail fore of the front wheels. Is this the selector switch?
>
> Sorry for the seemingly dumb questions. There will be many more. :?
>
> The diagrams in the manuals are no bueno.
> --
> 1976 Palm Beach
> Austin, TX
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Indeed, they are! A thousand works is what I'm in for, I'm sure. :d

Troubles with my Photobucket prevent that at the moment.

So it turns out that of the three hoses that run to the selector switch, the one running to the front of the coach is cut and blocked with a bolt.
Another is the host that is open, and the very hose that the fuel was originally leaking from to start this whole mess.
The third is running to the top of the aux tank.

This leads me to believe that the PO chose to combine the tanks? Would that explain it?
--
1976 Palm Beach
Austin, TX
 
Adam,

There were no stock connections to the bottom of the tanks - ever.

It sounds like you have a seriously cobbled mess there. There is a movement here to use the drain plugs to connect the tanks. While this may seem
convenient, my coach shows strike damage to the tanks and transmission pan that would make me worry. The other thing is the unfortunate fact that the
mod eliminates any possibility of fuel inventory management.

With the APU (generator) pulling from the bottom of both tanks, you have an opportunity unique in the GMC world. You could run the fuel down enough
to immobilize the coach just by running the generator.

Here is a link to a good diagram:
http://www.gmcmhphotos.com/photos/search.php?searchid=282701&cpage=14
I hope this is a help.

With the exception of the problems directly related to crapahol, the designed fuel system is quite effective - if it all works. Repairing it is not
an insurmountable task. It does take some determination, and I have done it all....

Matt

> I've been under the coach trying to map out what the PO did so I can decide how to move forward.
>
> I found out first that the line with the bolt in it, was about 18 inches long, and was open on the other end, connected to nothing. 8o
>
> Some questions-
>
> The connections on the bottom corner of each tank....these are what?
> On my coach they are connected, including a t and a pump. The pump appears to run to the Onan.
>
> There is a connection mounted to the driver side rail fore of the front wheels. Is this the selector switch?
>
> Sorry for the seemingly dumb questions. There will be many more. :?
>
> The diagrams in the manuals are no bueno.


> Indeed, they are! A thousand works is what I'm in for, I'm sure. :d
>
> Troubles with my Photobucket prevent that at the moment.
>
> So it turns out that of the three hoses that run to the selector switch, the one running to the front of the coach is cut and blocked with a bolt.
>
> Another is the host that is open, and the very hose that the fuel was originally leaking from to start this whole mess.
> The third is running to the top of the aux tank.
>
> This leads me to believe that the PO chose to combine the tanks? Would that explain it?

--
Matt & Mary Colie - Members GMCMI, GMCGL, GMCES
'73 Glacier 23 - Still Loving OE Rear Drum Brake with Applied Control Arms
Now with both true Keyless and remote entry
SE Michigan - Twixt A2 and Detroit
 
I worked on a coach once that had the two drain ports cobbled together. The person that did this also added a piece of angle iron to cover the ports
and the line between the two tanks. While there were no marks on the tanks there sure were a lot of scratches on the angle iron.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
selector switch. You can see one of the two hoses cut and plugged. that one goes forward to the engine. the other is the one that was leaking fuel.
the third goes to the top of the main tank?

Layout of tanks as I can tell. This is the bottom view, meaning the tanks are combined through the drain plugs.

filter and pump. Pump goes from main tank to generator. I followed the wire to the front, into the dash, under the steering wheel, where it is not
connected to anything, and taped. I suppose that this allowed the Onan to run the main tank to the very bottom. this also explains some
inconsistencies I noticed with the fuel tanks while driving.

initial view of under the coach. lines hanging like this.

I plan on re plumbing this to spec.

lets here your arguments! thoughts? Ideas? anything I should do or not do while the tanks are dropped?


--
1976 Palm Beach
Austin, TX
 
Adam, The top of the heap in fuel systems seems to be with an electric pump
installed in the tanks in each tank. The controls seem to be with a
selector switch to power each pump separately. Eliminate the tank selector
valve with one way check valves on each output line, followed by a single
line to the carb or fuel injection unit of your choice. Obviously all metal
lines instead of hoses where possible.
Second choice is a stock hook up with Gates Barrier hoses, new selector
valve followed by a carter 4070 electric fuel pump hooked in the auxillary
fuel line or alternately in the single supply line to the carb or
injection. Wire the pump to the tank selector switch and when vapor lock
rears it's ugly head, just switch to the aux tank and supply pump. Filters
should be made of metal, not clear plastic.
Other variations are out there, but both of the above set ups will result
in a trouble free fuel delivery system.
Jim Hupy
Salem, OR
78 GMC Royale 403

>
>
> selector switch. You can see one of the two hoses cut and plugged. that
> one goes forward to the engine. the other is the one that was leaking fuel.
> the third goes to the top of the main tank?
>
>
>
> Layout of tanks as I can tell. This is the bottom view, meaning the tanks
> are combined through the drain plugs.
>
>
>
> filter and pump. Pump goes from main tank to generator. I followed the
> wire to the front, into the dash, under the steering wheel, where it is not
> connected to anything, and taped. I suppose that this allowed the Onan to
> run the main tank to the very bottom. this also explains some
> inconsistencies I noticed with the fuel tanks while driving.
>
>
>
> initial view of under the coach. lines hanging like this.
>
> I plan on re plumbing this to spec.
>
> lets here your arguments! thoughts? Ideas? anything I should do or not
> do while the tanks are dropped?
>
>
>
>
> --
> 1976 Palm Beach
> Austin, TX
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
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