I just purchased this boat about a month ago and noticed that it has a substantial oil leak. I cant find the leak but it just leaks after you run it for a while and cut it off then it leaks while its not running. The guy that I purchased it from said that it was a 4.3 litre volvo but the intake has GM stamped on it. If I have to pull the engine to fix the leak then I want to go ahead and rebuild the engine. Is it possible that this is a GM and can conventional 4.3 automobile parts be used to do this? Thanks.