This may help someone out in the future. I order a new gasket that goes around the fuel filler neck of a Max IV, it needed to be replaced do to dry rot. The new gasket was hard and stiff. I tried using dish soap was no help. Not sure where I got this, I put the gasket in a pan of water, brought it to a boil for two minutes, took gasket, pan and all into the garage. With the help of a large flat tipped screwdriver the gasket went in very easily.

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