Plastic rear main tank not sealing

[tk1218]

I have a brand new plastic rear main tank from broncograveyard that I'm having trouble getting sealed. The sending unit and oring are also new.

On the second attempt I put some rtv on the 6 bolts thinking they might be the issue with no improvement in the leak

Any thoughts on how to get this tank to seal?

Thanks

 

[DirtDonk]

Got a picture? You're talking about a replacement tank for a pre-77, correct? From the sound of it with your mentioning the bolts, I think this type of tank is known for having leak issues. I've never personally experienced it, but maybe others here have and can comment.

 

[pbwcr]

Thee are plenty of gasoline compatible sealants available. Find one and use it.
The one I like best is sold by Yamaha. Not permanent. Expensive for a rather for the size of the tube.

 

[tk1218]

Thanks for the replies

Yes, it's a replacement tank for a 66

Here are some pics

It's not leaking much right now as I've drained it down to 1/3 tank

 

[Rustytruck]

I just installed a new metal rear tank in my 1974 and the seal that came for it was too skinny square cut seal ring. I could see where there would be no compression on the sending unit to seal before using the lock ring. when I ordered the new tank I ordered extra o-rings so I didn't use the square cut o-ring and used the thicker round o-ring of the extra ones I bought. I was disappointed in the seal but the tank and everything i got was great except that seal was no way it would work. cant buy anything these days without some form of hassle. I don't blame the vendor when the supplier cant see obvious failure of their own parts. Of courses I know what to look for and double check and question everything these days.