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Fuel line leak

This topic can be found at:
https://www.barthmobile.com/eve/forums/a/tpc/f/3631087061/m/6513912097

07-18-2017, 12:02 PM
Steve Griffin
Fuel line leak
We are packing to leave for New Mexico and I noticed a little drip after I shut off the engine in the driveway. It stopped after a couple of minutes. I crawled under there and found that the rubber lines from the top of tank are probably original (1978), brittle and a little porous. I thought I would loosen the (vey rusty) straps and lower the tank...BUT the brackets that hold it to the frame are WELDED on and not bolted to the frame. I think the tank is too long to slide out the back, it would hit the rear wheels. It looks like it was installed before the structure was built around it closing it out. Anyone else have this problem?? This looks like it might spoil our vacation.
07-18-2017, 12:33 PM
bud@YXY
Our 1977 21 ft has two tanks --- the starboard (right/passenger) side is conventionally held on with straps and bolts, but the port (left) side bracket, is like yours --- welded to the frame. I have wondered if this was just our coach's issue or if this was routinely done by Barth.

Bud


1993 Breakaway 36ft & 1977 20 ft
Spartan: air ride and brakes & P32(?)
Cummins: 8.3 litre 250hp, PACBrake
Allison 3060 (6 spd)
Front entry, side hallway
7.5 kw diesel gen.
1999 2dr Tracker 4X4 5spd, SMI Braking system
07-18-2017, 12:37 PM
Steve VW
One of my pet peeves with the gas coaches. In tank pumps, etc, require access and you can't get to them easily. head bang

I got lucky on my side tank. It is located under the bed so I could cut an access hole through the floor and service from above. Not so lucky on the main tank.





Good luck.


9708-M0037-37MM-01
"98" Monarch 37
Spartan MM, 6 spd Allison
Cummins 8.3 325+ hp
07-18-2017, 03:19 PM
Steve Griffin
That was my fear. I can't believe they would box me in like that with perishable lines and a sending unit closed out. The only other way to access is to remove the right hand lower outside panels, cut out the support structure and take the tank out the side. We are leaving tomorrow for a rafting trip on the Chama River and planned camping at a high Lake near there, but now I guess it will be a car trip instead and motels. We are cancelling all our RV Park reservations and starting over.

I haven't measured yet, and won't be able to do any heavy deconstruction until we get back, but I think I might be able cut a trap door under the dinette. I may have to take out the forward bench to do that but it would be better than cutting out the side of the coach. I'm thinking a hinged door with a metal flange all around to provide a seal surface. It will have to be large enough to service the float valve (gas gauge sending unit) in case (when) that needs to happen. I just hope I can get it either entirely under the bench or entirely under the table and not in-between.
07-18-2017, 11:14 PM
Mogan David
I feel your pain Sorry
one of the major projects I had to have performed by Bernd's men at World Line Motors, Nacogdoches, TX was new fuel lines to motive power and generator engine. The 1998 or 1999 rubber fuel lines had become punky and leaked. Actually, the leak first manifested itself as sucking air into the generator fuel line, causing it to stall.
Be glad that at least the underside of your Barth is all accessible.
Almost everything is boxed in by bulkheads and belly pan with the monocoque ForeTravel UNIhome construction.
08-04-2017, 05:05 PM
Duane88
I am having problems with fuel flow, I wonder if our problems are similar, is the fuel pick in the center of both the front and rear tank? I would like to get at both areas. Mine is an 82 Thanks Duane
08-04-2017, 06:50 PM
Steve Griffin
Our coach only has one 30-something gallon tank, on the passenger side. The pickup fittings are in roughly the center side to side but forward of center front to back. Once I got the location I removed the dinette benches and cut an access hole. Unfortunately, there was a steel tube structural member directly above the pickup fitting. I was able to get to the lines but if I ever need to service the float valve, I will have to either cut out the steel tube and weld it back or cut off the tank brackets and replace with bolt-on ones.
08-04-2017, 07:24 PM
Steve Griffin
One other thing...and this is VERY important. Be careful what fuel lines your friendly parts store tries to sell you. Do NOT use SAE30R6 or SAE30R7 lines. They are NOT for gasoline with ethanol blend and will deteriorate rapidly if used with the blended fuels that we are forced to endure today. It is hard to believe that after all these years the stores still stock that stuff, but they do. Use only SAE30R9 (high pressure) or SAE30R14 (low pressure) lines as they are compatible with ethanol blended gasoline. Gates calls theirs "Greenline" or "Barrier" fuel lines. It is too big a hassle to get to the top of your fuel tank to use the incorrect lines and then have to do it all over again a couple of years down the road!
08-04-2017, 07:40 PM
Duane88
I would have never thought they stock fuel line not compatible with alcohol in this day and age. That may save me time and frustration. I think I will cut the tank straps if I have to and as you suggested go with bolt on. I read the other fuel problems folks here have had and I guess the best thing to do is go full bore. I have a full tank and a half tank of gas, I hope when I pump it out and pour it through a filter I can put in my cars.
08-04-2017, 09:03 PM
Duane88
I was looking to find fuel system parts and saw that the gasket between the carburetor and intake manifold is called a "heat insulator" and mine is pretty thick about .25 inches. I used gas to prime the system during my time in hell trip and did notice it would boil if I poured it on metal in the carburetor. I wonder, it seemed to take about the same length of time between problems, and when it was started cold the thing ran fine for 60-80 miles. So is it possible the carburetor just gets hot and vapor locks? Bye the way, I can not find a fuel pick up sending unit for my 30 gallon tanks, only for 40. No fuel pumps in these tanks either. Just the mechanical unit.

When I look at the front of the standard vrs the Glassnose I think air passage looks like it is better on the standard, is this another problem??

Going nuts in Iowa!!!
08-05-2017, 06:22 AM
crouch38
GM had a problem with vapor locking back in the 80's . The fix was to add an external electric pusher fuel pump to the p30 chassis . It is a low pressure (5 to 8 ) fuel pump mounted on the frame rail close to the tank . it is recommended to place an inline filter before the pump .

My 86 barth was mounted on a 85 chassis. Doesn't have intank fuel pump .
Has a canister fuel filter, inline fuel pump, then regulator on frame rail just ahead of tank . also has a fuel pump on side of 454 engine .
Bob


Year:: 1986
Model:: Barth Regal
Length:: 25 ft
Engine:: New Chevy 454 HO
Chassis:: P-30
Data Tag Number:: 8606 3339 25FP2
08-05-2017, 08:23 AM
Steve VW
You may have a stuck heat riser valve (also called EFE valve by GM)

On one side the exhaust manifold has a flapper valve near the exit port. It is supposed to close when cold, forcing exhaust across the engine through the intake manifold and out the other side. If it sticks shut the intake manifold will be really hot uner the carb. Some are vacuum operated some have a bimetal spring.

https://www.barthmobile.com/eve...543915387#3543915387

Good luck.

Be sure it is free to open or wire it open for testng


9708-M0037-37MM-01
"98" Monarch 37
Spartan MM, 6 spd Allison
Cummins 8.3 325+ hp
08-05-2017, 10:24 AM
Duane88
Geez; the flapper valve on this old beast has not worked in years. It is frozen in the closed postion. I looked at that when I got my Barth, but assumed it was burned away, going to pull it out. It gets cold in Iowa I guess I need a whole new set up, or just let the engine warm a longer time.

The fuel pump seems to be a great choice too. Thanks again all!!!
08-05-2017, 10:37 AM
Duane88
The regulator you mention is it in the return line or supply line? I have two tanks. So I would put the pump after the selector valve, that's several feet from the fuel tanks. Should I install the regulator after the pump or in the return line.
08-05-2017, 11:05 AM
Duane88
Another thought, I put a water temp gauge in the port vacated by the ported vacuum switch that ran the flapper valve, the temp got to around 115C during this trip, before it only hit like 105C. I have hope!!!