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Can I please get some help identifying compression number on my 1988 Yamaha 90 hp outboard. I just did a compression test with the motor warm and all plugs out. I got between 80 and 82 on all 3 cylinder. I understand that I am looking for all cylinders to be in the same range.My question is I have seen used Yamaha 90 hp motors for sale that had number over 100? Could this be an issue? Not a ring but crank seal etc? The motor has been running very well and appears to have plenty of power mounted on a 17 ft Montauk and moves it well. I have had to Boat for a few years and I do know the cylinder head was replaced but other than that I have knowledge of a rebuild or any other work. I just want to make sure if I have an issue lurking I can get a grab on it in the off season.Thank you for any help you can provide.
