I recently bought a very good condition gas tank and while removing the fuel pump, one of the small screws broke from being rusted stuck. I fiddled with pliers and it just made it worse breaking off more and more until there is nothing left to get hold of. This screw is tiny...how can I get it out of there? Would it be so bad as to just forget about it and leave it? I thought about using a screw extractor but it is really really small and I don't know if it would work. Also thought about just trying to drill it out...

 

spray it down with some PB blaster and let it soak in for a few days, periodically refreshing the lubricant.

after the days passed, take a dremel with a cutoff wheel and cut a straight slit in the head trying not to damage the pump seal surface. use a flat head screwdriver and carefully try to remove the screw. if it still won't budge and rounds off then your only alternative is to either weld a tack bead to the head of the screw trying not to weld the screw to the housing, so you can get some pliers onto it with a good grip. if that all fails then you can only drill and rethread the hole.

realistically you would probably be fine not having the one screw, but that is your gamble and it may leak when the tank is full.

 

I agree. I would IMO if it was me let it Fly. Because i have a missing screw and mine has no issues.. No spilling gas. No air leaks. its a rubber seal so it should be ok. But thats me.

 

Just drill out the broken piece trying not to enlarge the hole bigger then it is and send in a small self tapping screw. Done.

 

All good suggestions. I think I will try cutting a slit with my dremel and if that doesn't work then I will drill out the center and try a self tapping screw or a small extractor. Would WD-40 do the same job as PB Blaster? What about Liquid Wrench?

 

IMO wd40 is only beneficial to the guy that makes and sells it ,better than nothing . If you can , use a penetrating fluid of some kind .. Liquid wrench is the better of the two for penetrating rust . Be careful if you use a a dremel or any kind of tool that you don't blow it to hell with sparks and gas fumes ,, ( it don't take much even if the tank is empty and dry or the hole is covered there will still be volatile fumes present )