Reservoir won’t stay screwed on tight

Hi gang - I took the reservoir off my Sea Swing to service it and now I can’t seem to get it back on securely.

Can I use Loctite? Also, do I need to replace the lead washer each time the joint is opened?

Thanks.

 

use teflon washer

 

I haven't seen one.
I assume the cutout needs to line up with the filler, so I would say "yes" the lead washer needs to be replaced. A Lead washer relies on compressing a little further each time.

 

Thanks. Okay - new washer installed. But the tank still not stay on tightly. The slightest knock counterclockwise causes it to back off.

Do you guys think I can use high temp thread seal?

 

What changed to create the issue? Add new washers someplace? Unsafe to use now.
Duane