fuel system on a 70 396 SS [Archive] - Chevelle Tech

: fuel system on a 70 396 SS

70 nialator
May 6th, 04, 1:32 PM
I have a few questions all relating to the fuel system on a 70 396 SS. My sending unit stopped working. Iím sure itís that because when I ground the brown wire the gauge goes to empty. I have 3 problems.
1. My tank seems to build up excessive pressure after I drive it for a while and remove the filler cap there is quite an air discharge. Return line blocked?
2. The filler neck leaks a little around the seem where it meets the tank. What is the best way to seal this? I have an oxy/acetylene set should I just re-solder / re-braze it. Flame around a tank makes me a bit nervous.
3. Are the sending units repairable and is it possible that some of the symptoms are related? The tank was building pressure even when the sending unit was working. ** If this is in the wrong category ďwiring - ele.Ē I apologize

Thanks for any advise,

May 6th, 04, 2:01 PM
DO NOT put any open flame around the tank. Remove the tank and take it to a pro to fix. Some radiator shops will also work on tanks, call around. They will vat it, purge then correctly repair. Then you can install a new sender and bolt it up.

mr 4 speed
May 6th, 04, 2:11 PM
What D1 said..or just get a new tank.I don't think the return would clog and have that problem..my 70 SS and 68 Cutlass have no returns,and I have no problems with excess pressure.Make sure the tank vents aren't clogged.

70 nialator
May 6th, 04, 2:19 PM
Thanks for the input, I guess I should have added that I had no intentions of trying to fix it on the car with fuel in it. With the tank empty and flushed with a non-flammable substance I think I can pull if off. What about the sending units, repairable or just get a new one for 70.00?

May 6th, 04, 10:20 PM
The tank is much more dangerous when empty because more fumes are present. If you do try this, which I strongly advise against, you must be absolutely certain that there is no gasoline present to build up fumes. A friend of mine had his brother die trying this at home because the gas tank exploded.