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gas fuel tank removal for repair

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http://www.barthmobile.com/eve/forums/a/tpc/f/3631087061/m/2941092513

07-23-2008, 06:37 PM
Jim and Tere
gas fuel tank removal for repair
The gas tank has been reinstalled. I am now an expertSmiler If you have questions I may be able to help. I took some pics for documentation. I may not know how things work but I know how to take apart & put back together.

Tere


Jim and TereJim and Tere

1985 Regal
29' Chevy 454 P32
8411 3172 29FP3B
Gear Vendor 6 Speed Tranny
07-23-2008, 06:57 PM
Jim and Tere
We have a curious situation. There are three fuel lines going from the rear tank to the front of the MH. 2 attach to the 6 hole transfer unit & the other goes from front to rear without attaching to the transfer unit. Oddly from the transfer unit to the rear tank there is a 5/16" hose with a fuel filter on it & there is a 3/8" hose with a fuel filter on it. Isn't one of these supply & one return? & what is the third fuel line for? Our generator does operate off the rear fuel tank.
Thanks for all you input.
Tere


Jim and TereJim and Tere

1985 Regal
29' Chevy 454 P32
8411 3172 29FP3B
Gear Vendor 6 Speed Tranny
07-23-2008, 07:00 PM
Jim and Tere
Oh & why is there a fuel filter on a return line. Furthermore what is a return line for. Seems to me the fuel pump at the engine pulls fuel from tanks. One line right?! Why a return? Educate me.
Thanks,
Tere


Jim and TereJim and Tere

1985 Regal
29' Chevy 454 P32
8411 3172 29FP3B
Gear Vendor 6 Speed Tranny
07-24-2008, 06:19 PM
timnlana
Sparks and gas oh my.

Welders tell me their trick is drain a tank and then drop dry ice into the fuel tank before they start working. The tank is now full of CO2 and the oportunities for an enlighting experience are decreased.

Timothy
07-24-2008, 09:41 PM
bill h
quote:
Originally posted by timnlana:
Sparks and gas oh my.

Welders tell me their trick is drain a tank and then drop dry ice into the fuel tank before they start working. The tank is now full of CO2 and the oportunities for an enlighting experience are decreased.

Timothy


If the dry ice store is closed, I use a hose from the exhaust from a running engine. The heat purges remaining gasoline, and the CO does not support combustion.

I had a student in a class tell me he uses the blower output of a shop vac. Says the incoming fresh air makes the PPM rate too low to support combustion. We checked it out with a calibrated explosimeter, and he was right. Our safety standards were for jet A fuel, so I am not sure how wide a safety margin he had, but he is still alive.


.

84 30T PeeThirty-Something, 502 powered
07-24-2008, 09:48 PM
bill h
quote:
Originally posted by Jim and Tere:
Why a return? Thanks,
Tere


The return line is to keep fuel moving. This prevents vapor lock by getting rid of bubbles and the extra volume of fuel moving through the line keeps things a little cooler. The vapor return also gets involved with smog stuff, which changed from year to year, and was even different for different states and vehicle weights.

I still see my old 85 P30 SOB, but I can't remember if it had one tank or two, so memory is shaky here. Several of my MHs had two tanks, though. I envy you with your two tanks, though, as the smaller tank can hold high-octane for hill climbing and the other has the cheap stuff.


.

84 30T PeeThirty-Something, 502 powered
07-24-2008, 10:24 PM
Rusty
quote:
If the dry ice store is closed, I use a hose from the exhaust from a running engine. The heat purges remaining gasoline, and the CO does not support combustion.

I had a student in a class tell me he uses the blower output of a shop vac. Says the incoming fresh air makes the PPM rate too low to support combustion. We checked it out with a calibrated explosimeter, and he was right. Our safety standards were for jet A fuel, so I am not sure how wide a safety margin he had, but he is still alive.


Gaso has to be at a air:fuel rato of around 12:1 to 18:1 to combust. If the tank is dry, the shop-vac exhaust is plenty to render the tanks gas-free, if all the liquid has been drained. The dry ice is an excellent suggestion, but it doesn't render the tank gas-free - it just replaces the air with CO2 - which is fine, as long as the openings are at the top (CO2 is heavier than air.)


Rusty


MilSpec AMG 6.5L TD 230HP; built-to-order by Peninsular Engines:  Hi-pop injectors, gear-driven camshaft, non-waste-gated, high-output turbo, 18:1 pistons.  Fuel economy increased by 15-20%, power, WOW!"StaRV II"

'94 28' Breakaway: MilSpec AMG 6.5L TD 230HP

Nelson and Chester, not-spoiled Golden Retrievers

Sometimes I think we're alone in the universe, and sometimes I think we're not.
In either case the idea is quite staggering.
- Arthur C. Clarke

It was a woman who drove me to drink, and I've been searching thirty years to find her and thank her - W. C. Fields
07-25-2008, 09:52 AM
Jim and Tere
Thanks for the education on supply & return. I really liked the idea of using the two tanks, one for regular driving & one for load. I am gradually replacing my 3/8 & 5/16 fuel lines with marine fuel lines. Most of what is left is in good enough shape that I will wait for more wear & tear.

One little issue occurred while I was checking the other lines to the engine, to the rear tank, to the generator. While reaching up on top of the rear tank to see if I could feel the condition of the hoses @ the sending unit, yep you guessed it. Fortunately it was only the skin but it was a snake skin. Even though he was long gone, I packed up, & left the scene. No more reaching up to unknown, unseen areas without first checking things out with a mirror or an air hose or a fire hose. Something other than my exposed hand.

There you have it.

Tere


Jim and TereJim and Tere

1985 Regal
29' Chevy 454 P32
8411 3172 29FP3B
Gear Vendor 6 Speed Tranny
07-25-2008, 09:53 AM
Jim and Tere
The third metal line I was asking about was the brake line.
Tere


Jim and TereJim and Tere

1985 Regal
29' Chevy 454 P32
8411 3172 29FP3B
Gear Vendor 6 Speed Tranny
08-20-2008, 10:43 PM
BarthBluesmobile
Barth owners learn more about the fuel tank issues than other brands I figure, because the construction of the coach allows the rig to last for decades, and there will be use and rehab of the coach in there someplace.

Since with mine, I wanted to see what was up on the top of the tank, and knowing what could go wrong with rubber lines and hose clamps after 20 years, I figured I'd rather do it in my driveway than have a problem in Death Valley.

The removal of the 75 or 80 gallon tank was straightforward, remove the bolts at the ends, remove the bolts on the straps, and gently lower it via jacks, blocks, and 2x4 blocks. Having a crew of guys would help. I used cargo straps also, to ensure a problem wouldn't bring the tank down hard.

Down part way, it was easy to see that the return line from the pressure regulator was too short to allow the tank to reach the ground, so I removed one connection and that was that. Also, then filler line and the breather line need to be attended to as well.

With it on the ground, I found some brittle and cracking hose, and some quite rusty hose clamps. I was happy to have this finding happen in this way.

The assembly is the reverse of the removal. However the filler hose is a very stiff hose, and it feeds through a hole in the P30 frame to reach the tank, and the clearance to the tank and the frame is about an inch or less, and the connection point is up an inch. So laying on my back, wrestling this, I began to think that it would be a good final test for approval in the NASA astronaut program. Tomorrow, I'll tighten all bolts and clamps I haven't already done.

One pal at work gave me this suggestion, and this is worth something to anyone else rehabbing a Barth. I had redone the floor already, and he said, I should have done the tank inspection first, by cutting an access through the floor. It would have taken minutes. And then rebuild the floor after. The tank removal and installation probably took me working alone around 5 hours or more. Still, better five hours in my driveway, than waiting for a road service call should I have trouble on the highway.

Happy Motoring!
Matt


1987 Barth 27' P32 Chassis
Former State Police Command Post
Chevrolet 454
Gibson Exhaust
08-21-2008, 01:07 AM
olroy
I tried the access-through-the-floor method, chasing a leak in my fuel filler hose. As I recall, the aluminum floor beams are on about 12" centers. There's 5/8" plywood on top, fiberglass insulation between the beams, & a solid metal belly pan underneath. I decided I couldn't do much through a 12" square hole, I didn't want to disturb the structural integrity by cutting through the beams, & I thought it would be more discreet than not, to leave the metal belly pan intact. The work didn't accomplish my objective, but I learned something.

At the end, I cut out the metal pan under the black water holding tank, removed that tank, replaced the filler hose which ran across the top of the holding tank, repaired & reinstalled the holding tank, & re-skinned the bottom with what was on hand, some painted steel roof flashing, heavily gooped with undercoating, & attached with pop rivets.
08-21-2008, 09:10 AM
Jim and Tere
I have the solution! Someone with some extra $$$ needs to buy a camera on a flexible arm. Then rent it out to the rest of us!! I'm calling my cousin to see how much I can get one for. Stay tuned!


Jim and TereJim and Tere

1985 Regal
29' Chevy 454 P32
8411 3172 29FP3B
Gear Vendor 6 Speed Tranny
08-21-2008, 09:48 AM
Danny Z
My proctologist has one, but he won't lend it out. Frowner


Dan & Suzy Z
'81 Euro 28 - Slide Show
454 Chevy


Venice, Florida
08-21-2008, 10:55 AM
Jim and Tere
Re stiff fuel filler hose. Gates makes a fuel filler hose that has an integral spiral metal wire that runs the length of the hose. This hose is recommended by Gates when you have to have any bending much over 1/2". It is also good if the hose will experience any pinching when it goes through chassis members on the way to the tank. When we drop the rear tank, I will replace the fuel filler hose with this type.


Jim and TereJim and Tere

1985 Regal
29' Chevy 454 P32
8411 3172 29FP3B
Gear Vendor 6 Speed Tranny
08-21-2008, 12:46 PM
chrisW
quote:
Originally posted by Jim and Tere:
I have the solution! Someone with some extra $$$ needs to buy a camera on a flexible arm. Then rent it out to the rest of us!! I'm calling my cousin to see how much I can get one for. Stay tuned!


I have one - its made by Rigid and it works quite well.
http://www.ohiopowertool.com/p-664-ridgid-seesnake-micr...on-camera-25643.aspx
Saved me many hours of frustration!!!


1985 Regency 35'
8.2T Detriot Diesel / Allison
other toys - a bunch of old Porsches, a GT350 and a '65 mustang convertible.