Fuel Tanks

[Roy Jensen]

Hi all,
   I have a question about the fuel tanks on my 1980 Clipper.  I have 2 tanks that fill from the same fuel inlet.  I am curious as to the capacity of these 2 tanks.  I also have trouble filling them both as the fuel keeps bubbling up the spout.  Is this a common problem?

[Andy Illes]

Hiyya Roy

I don't know about your setup, mine's a single 36 gal '76... but as to the fuel bubbling back while filling... yeah, for some reason, a lot of us have that.  I found my vent was plugged and cleaning that helped some, as did clearning the charcoal canister line, but only for a while it seems... I still have to watch filling it or it bubbles back.  One mechanic told me it's cuz of what he thought was a too-sharp bend in the filler pipe that causes it to back up, but it seems to me that shouldn't make any difference if you're filling slowly.  

There have been quite a few comments about it, and I've not seen that anyone has solved it.... am I wrong?

[Roy Jensen]

Thanks Andy,
    I have had this problem with other moter homes because of the too sharp bend in the inlet piping as you have mentioned.  I wanted to be sure I was seeing the same thing.  I'malso wondering about the capicity of my fuel tanks, got any ideas/

Roy

[Andy Illes]

Sorry, but all I know is what this site sez... i.e. 36 and/or 50 gal.  I'm sure someone that has your setup will post to answer your Q.

Yeah, that bubbling thing gets pretty old, esp when you have to fill at a pump without a canopy... and it's raining, huh?  Other (non Clip) RVers have complained about their rigs doing the same thing, so I guess it's just something we live with, unless someone's found an answer.  The mechanic I mentioned faulted the bend at the bottom of the filler, where it angles over to the tank.  When I had my tank off, I thought about using hydraulic hose stock to replace the whole thing from the filler on, to straighten it out, but didn't.... can't remember why now.

[Rodney]

Years ago when I was a mechanic at the local GM dealership the fire managment bought several cab and chassis' for there tanker units. after they installed the boxes on the units everyone had that issue of filling slowly and having the air that has to escape the tank bubble the fuel back out the filler inlet. Not to big a deal unless you are off to put out a FIRE. Well they were so it was a big deal to them. I was elected to try and fix the problem which was to take the kinks and sharp bends out of the filler hoses and the smaller vent tube going to the tank. I also had to use in one area the spiral wire you see in radiator hoses to hold the larger filler hose open where the hose ran between the frame and box. My suggestion is to look close at the routing of the hoses for any kinks of sharpe turns that may restrict not only the fuel but the vent lines as well. as for filling both tanks with one filler is a strange design? could it be that one tank is filling first and covering the air vent to the other tank before is is full? I would have to see that to understand how that works.
let us know how it goes
Rodney

[Roy Jensen]

All,
   It appears my main tank is a 33 gallon factory tank with an auxiliary tank that holds about 20 gallons.  The way it is setup is the main tank fills first then backs up into the aux tank.  It appears that I will have to run off the aux tank first because if I run the main tank first it pulls some gas from the aux tank.  Pretty wierd setup.  I believe once the main is full and it backs up to the aux tank is where my bubbling up is happening.  At least I think I have it figured out now.

[terry and karen conkle]

We have dual tanks on our 79 Chevy.  On our first trip to fill up, we discovered a major leak due to the rotted rubber vent hose from the main tank back to the filler orifice.  Curiously, our Clipper was plumbed from the filler orifice to the main tank and secondary tank with PVC pipe.  In two different places, some connections were screwed-together PVC which allowed gas to seep past the threads. I then had to empty the main tank and drop the tank to get to the rotted vent hose, and  I subsequently replaced all the PVC pipe with high quality straight and bent rubber radiator hoses.  I plan to replace these radiator hoses with  Dayton brand fuel hose as soon as I find a distributor.

As for filling the primary and secondary tanks, I'm sure the main tank fills first, and gravity forces fuel into the second tank.  However, we don't  know how much our secondary tank holds, since we haven't had the opportunity to take our Clipper on the road yet.  We're sure that our primary tank holds 36 gallons.  Our secondary tank is an add-on, and as soon as we run all the gas out of the secondary tank and refill, then we'll know how much it holds!  

We've taken care of fuel tanks and hoses, replaced the starter and battery, replaced the water pump for the house, replaced the fresh water tank and plumbing, got the Onan generator running perfectly, replaced roof vents, refinished the interior cabinets, thoroughly cleaned, added some gear, tested all of the appliances (which all work well), and we're ready to go on our first outing.  Wish us luck!

Terry and Karen