Total Rebuild of a 1979 Dodge Class C

oldtrucker63 wrote:
Anyone know what could make the gas flow back to the tank when the motor is shut off, The carb will not hold prime when the Engine is shut off, I'm thinking it is a seal in the fuel pump,.?? :h

It's been awhile, but I'm back around again after the flooding...working on the fuel tanks and waiting on a new sender (#FG61B)...which probably won't be the right one...which I'll probably have to modify to work...

Do you still have the original Thermo-Quad carb on top?
If so, I'll bet you're about ready for a bit of a rebuild and some sanding if you haven't already.
Turns out the Thermo-Quad likes to leak around the top and bottom (more like the bottom) of the phenolic center section after it gets tightened down a bit too much, or after some age.
The fix for mine was to tear it down completely, get the phenolic/plastic center section off by itself, completely stripped, and lightly sand the top and bottom of it on some 600 grit wet/dry. Before I sanded mine, I could visibly see just a tad bit of warp in the bowl when I laid it on a flat table, and it was right where fuel would sit up against a gasket.
Jist of the story, the fuel probably isn't bleeding back into the tank, it's more likely leaking down into the intake manifold. And since we're dealing with a big ol' 440 engine, we probably wouldn't notice a cup full of gas in the intake upon starting the engine. If you re-check those videos I did on youtube concerning the Thermo-Quad, I'm relatively sure I mentioned it in one of them...somewhere...
On another subject, does your rig have a steel, almost perfectly rectangular rear fuel tank? Mine does, and it has about 6 inches of clearance to the front and rear of it. I'm thinking about welding on a "saddle" to the front and rear to increase it's capacity from ~36 gallons to around ~49 gallons if my measurements are right...

JDG