Boat question

[watermedic]

This is a question about a Yamaha 310 boat. I am hoping that some of you may have some knowledge to share about them. This is my nephew's boat, so forgive me for not having the best information.

The boat has a "clean-out" port for each jet drive. After storage the rubber plugs will not come out. He has sprayed penetrating oil on them etc. Do any of you know a way of getting these stuck plugs out without damaging anything?

I have posted this on the Yamaha forum also, but haven't gotten a response yet.

[cyoungesq]

Try dumping a bag of ice on the top of the plugs, the theory being that the rubber will contract much more significantly that the surrounding fiberglass and/or metal. Wait 20 mins, then try twisting it out.

[watermedic]

Thanks for the reply and tip and thanks to Kaybat for the PM and help.