making a large gasket for manway???

[john11139]

I need to make a large gasket (21" dia) for my pumper truck. I have not been able to purchase one of the right size. Basically it is a square gasket about 5/8". in a u channel. I was wondering if I just buy a tube of byutal rubber like you use in a calking gun would hold up or should I use a more rigid material, something like a polypurpoline? I imagine being this thick that it would take some time to cure.

 

[Red05GT]

What about the sealant tape that septic tank companies use in the tongue and groove
between the two tank halves? It is about 3/4" square.

 

[nanan00]

You can get the rtv gasket stuff in calk tubes or give Gulf Coast Rubber a call and get them to make you a to size gasket.