Frustrated by the black tank

[ND10CentCan]

I have posted on my thread about our restoration of the 1976 31' Sovereign with our frustrations with the black tank. No one has responded yet and we need help.

We bought what was called the "correct replica tank" for it and the threads on the tank do not match the original metal flange that screws into the tank. We tried another one after buying it from the local RV dealer. That doesn't work either. DH says he is totally frustrated trying to get something to work on that tank. Does anyone know what else we can do? A source for other flanges? Retrofits? Hints, suggestions, ideas, thoughts, and guessed appreciated.
Sandy

[xrvr]

Try Inland RV at least for advice. jim

[Lance M]

Sandy,
Uffda! The toilet inlet on the tank should be a 3"FPT (female). New toilet flanges come in a variety of combinations and sizes, but they are all 3" You need a 3" MPT (male) toilet flange. Most of the old metal toilet flanges are 3" MPT. They can be very difficult to get the threads started. Post some pics. Tell him to get back out there and git r done.

[ND10CentCan]

Originally Posted by Top

Sandy,
Uffda! The toilet inlet on the tank should be a 3"FPT (female). New toilet flanges come in a variety of combinations and sizes, but they are all 3" You need a 3" MPT (male) toilet flange. Most of the old metal toilet flanges are 3" MPT. They can be very difficult to get the threads started. Post some pics. Tell him to get back out there and git r done.

UFFDA is right! He has gotten so frustrated that he headed to town to order Formica, get some fasteners, some fittings, and maybe a gigantic bottle of Excedrin. Or a bottle of something I expected him back by now but maybe he sees the error of his ways and has headed to Montana...or Canada. I will pass your message along. He has been hesitant to try to put too much force on it and bugger up the threads. I wonder if he just needs to really apply some pressure? Thanks for your help.
Sandy

[Minno]

Can he get the flange started into the threads at all? If yes, but it seems like way too much force is needed to screw it in all the way, some liquid pipe joint compound should help. It will provide lubrication to help the flange seat into the opening all the way, and then, as an added bonus, seal the threads once you're done.

Chris

[Wabbiteer]

Cold plastic tank fittings can fight back - anything in North Dakota might use a little warming up even this winter? Just mild heat, hair drier blah, blah on the tanks FPT threaded insert to get it expanded out some. And some vegetable oil on the threads might help keep something resembling friction welding down...

[ND10CentCan]

DH finally returned from home and he took the advice given above and finally got the flange into the tank. PHEW!! It took some persuasion and some Norwegian courtesy comments but it is in, hopefully for good. I was on the roof of the Albatross trying to lift some layers of silicone when I heard it all. Thanks for everyone's advice when we needed it.
Sandy