The Chevy Owners and Drivers manual for my '85 28' Regal says that the fuel tank capacity is 40 gallons. Barth's factory order says 70 gallons so I assume that the forward tank Barth added is 30 gallons. The street side, rear mounted, generator, runs of the rear tank(whose fuel level sending unit is stuck on "full"). Problem is that my generator stopped and it only took 22 gallons to fill up the rear tank. Can you adjust the level at which the generator will shut off? And does anybody have any ideas about how to 'unstick' my stuck sending unit? Hope I don't have to drop the tank. Sure would like to get a little more run time out of the generator.
Thanks for the help.

The genset draws from a tube that extends down into the tank. The length of the tube determines how much fuel the genset can suck before it sucks air. A longer tube will allow it to suck more fuel.

It is possible that there is a bad connection somewhere in the circuit from the sending unit to the selector switch. The selector switch could be bad, too. Cleaning and reseating the connection at the top of the tank might help. Can you reach it without dropping the tank? Make sure the sending unit has a good ground to the frame.

The sending unit and its wiring can be checked at the selector switch with an ohmmeter. The readings to ground should be quite different with the tank full and empty. The sending unit itself can be checked the same way if you can get to the connection.

I had the same problem with the rear tank reading full all the time. Traced it to the selector switch. Took the old switch apart and found that the grease in switch had hardened preventing contact, works now. I have the same 40gal---30gal set up but the gen set pulls fuel from the forward 30
gal tank

The Fuel Sender Unit on the 40 gallon gas
tank was designed with a separate tube with
a pressed fit cap that could be punctured
with a sharp tool and used to feed the gen
set. The tube was designed to leave approx.
5 gallons of fuel in the tank when the gen
set ran out out of fuel. We, the design engineers, agreed that 35 to 40 miles range
would be enough to get your motorhome to the
nearest gas station.

Jake Jacobson

One more thing here---is the rear tank in question a Chevy tank or a Barth tank? My 84 has a tank in back made by Barth. I believe the genset shuts off at about 1/4, which would be 20 gallons left. I like having a lot of gas left because we are often very far out in the boonies.

I believe the rear tank is Chevy because it's steel and has no drain plug. The Barth tank is aluminum and has the drain plug. Charles, can you tell me where the fuel selector switch is? The rocker is on the dash and I presume the switch is somewhere underneath the Barth. Thanks
Jim

Jim, FWIW, my Barth-made tank is steel. The Chevy tank looks stamped out and rounded, while the Barth tanks look fabricated of sheet stock.

If you hear a click when you switch tanks, you can look for the solenoid valve by following the click. It is probably a silver colored cylinder with a black plastic end with three hoses going to it.

Thanks Bill. The Chevy tank is stamped out like you described. The Barth tank is made of nice sheet stock. I'll get under Barth soon and look for the selenoid. Problem is, it's in Tere's 85 year old aunts' driveway, and these little red ants are waiting for me each time. Someday, I'm going to build a Barth garage.
Jim

Jim
The fuel gage selector is in the rocker switch on the panel

Charles