Busted Fuel Tank Sender Unit Screws

[John_W]

Hi guys,

I'm working on a BN-1 restoration project and have a little challenge with the fuel tank sender unit. As I was removing the original fuel tank sender unit, I noticed that the head of 1 the 6 screws was broken off long ago. 4 of the remaining 5 screws came out fine and the head of the last screw broke off. So I now have 4 of the 6 screws in good working order and 2 of the 6 are busted off. The male portion of the screw remains in the female portion of the tank fitting.

The problem screws are sort of diagonally opposed (not next to each other). I can think of two options: 1) try to drill out and hope not to damage the treads; or 2) leave as is and use a little extra fuel resistant tank sealant

Any pearly words of wisdom for me on this one?

Thanks.

John W

 

[BigGreen]

I would go for option 2
No need for a very tight fit
Do take the original type of bolts

Hans

 

[57_BN4]

That is one of those issues where I know I'll think about it while driving unless I get the broken ones out and replace them. Had the exact same thing happen on my tank.

The female threads are in a brass ring which is soldered in two places to the underside of the tank (assuming BN1 is same as BN4). I'm pretty sure the two that break are related somehow to the soldering, perhaps the flux wasn't cleaned and causes the threads to corrode more than the others. I ended up unsoldering the tank sides to repair rust and managed to unwind the broken ones by gripping onto the threads protruding out of the under side of the brass ring. They weren't very firmly stuck.

You should be able to get them out relatively safely if you first make a piloting jig out of 1/4" steel plate to bolt on top so the drill doesn't wander. Fairly involved though and as mentioned- probably ok to just reinstall it with four screws.

Andy.

 

[BlueRidge1]

John,

My first concern would be,is there gasoline or fumes present in the tank before you start the drilling process?

Bob

 

[Legal Bill]

I'd drill them out if I could not get them out with a vice grip.

 

[Bob_Spidell]

I've had some success with 'left hand' drill bits; you drill in the opposite direction and often the bit will extract the screw without needing an extractor.

 

[57_BN4]

Bob- as these ones go right through, an unsharpened regular drill bit will heat the remaining screw enough to fire it right out the other side.

Andy.

 

[John_W]

Thanks for the advice on this. I will try drilling them out.

I also appreciate the safety concern raised by Blue Ridge Bob. My tank has been empty for >30 years and well purged.

Thanks.

John