Gas Tank

Recently replaced the gas tank in 97 s10 blazer . The tank leak during filling.I ran the blazer to see if it would through a code . No codes I belive the vent in the front of the tank could be the problem. The leak only happens when clear full.:banghead: :banghead:

Recently replaced the gas tank in 97 s10 blazer . The tank leak during filling.I ran the blazer to see if it would through a code . No codes I belive the vent in the front of the tank could be the problem. The leak only happens when clear full.:banghead: :banghead:


You need to look under it and find where the leak is coming from.
But be careful gas leak or fumes will blow and burn you if there is a open flame any where around.
That can includes a heater within 25 ft of it or drop light or smoking near it or a spark from static electric or spark from engine.
In cold weather gasoline fumes will head/walk a long ways on cold concrete floor to find a ignition source.
So Be careful.
MT

The gas tank is new . During the purge no codes show up . This leads me to think that the problem is with the vent at the front of the tank. I could be wrong but I think what is happening . Is during fueling the pressure is pushing gas out the vent. During the pruge cycle the vent is pulling down and sealing. That is showing the closed system.

Does it leak when filling the tank or just after it is started and running?
When filling up tank there should be no pressure on tank?
After fill up and engine is started there should be vacuum on tank.
Craw under there and see if there is a outside tank gas leak.
MT

If leak when filling then it can be coming from the filler tube ?

if you over fill the tank it will leak out of the filler neck.

If it leaks at the filler neck it would through a code like po440. I think its pulling the vent down and sealing. During filling it pushes gas out the vent or around the vent.

I found the leak . When I put the pump back in the gasket must of not seated or the gasket is cut . I have to wait to pull the tank had to fill it to verify were the leak was.

It's been a couple weeks since last post on the tank problem. My update is that when I installed the o-ring on the sending . The o-ring was to large . When I put the sending unit in the tank it push the o-ring down past the seat and cut it leaving a gap for gas to rush out when filling. My advice if you buy a aftermarket tank spend the money for OEM o-ring . Plan ahead you will more than likly have to order it.:iceslolan