Best Glue to Use for Tank Work?

[Don curt]

I have followed Peggie's advise with my one vent line in my holding take, e.g. cleaned, straightened etc.I think a second vent would help. I have to cut a hole in the top of the plastic (polypropelene??) tank to add a vent hose fitting.What would be the best way to glue this fitting in and with what glue?Don

 

[Peggie Hall/Head Mistress]

No glue, Don...nothing with bond to polyethylene

You need access to the inside of the tank--an inspection port--to install a fitting in it. Buy a "bulkhead" fitting--the kind that's threaded and has a nut that tightens against the bulkhead or hull. Use a hole saw to drill a hole that's a VERY tight fit for the fitting....reach into the tank through the inspection port and insert the fitting...the threads and the nut go OUTside the tank. Make a rubber gasket to go under the nut...it too should be a VERY tight fit. When you put it on the fitting and tighten down the nut, you'll have a leak-proof seal.

 

[Don curt]

Access Port?

Thanks for the quick response. I really don't think I have an access port. The only thing is maybe I can reach thru the hole for the bellows type gague which doesn't work anyway.By the way that cover on the gague opening is only screwed on to the less than 1/16th inch thick tank top and has some caulking around it.Boat is Hunter 336.

 

[Peggie Hall/Head Mistress]

Only 1/16" thick??? Wow...that's THIN!

All the caulk is doing is filling up space...it's not sealing anything. But if you can get your hand into the opening for gauge, you still should be able to do it. I'm also in Atlanta (for the next week, anyway)...so if you'd like to kick this around, e-mail me and I'll give you a phone number.