I tried searching the forums but had no luck. I have a 71' F-150 that pushes fuel out of the rear tanks gas cap. I searched on Google and saw mention of re-placing the front fuel pump as it has a faulty check valve. I would like to get your opinion on this along with any other possible causes. If it is the fuel pump how difficult is this to replace?

It happened again today when I was sitting and idling for 5-10 minutes.

Thanks!,.....

 

This is a 1971 F150? There is only one pump on this engine. Are you sure you didn't mean a 1991 f150? It has pumps in the fuel tanks. If this is the case, then the problem is a weak check valve in the pump that is allowing fuel back into the tank.

 

Yes it was my gooot typing, it is a 1991 F-150.

thanks...

 

Oldtimer hit it right on the button. Should not be a big deal to have it replaced.

 

There is a recall on that and the dealer will repair. They used to replace the fuel pump but the last recall was to install an in line check valve and replace the pressure regulator.