[THEFERMANATOR]

If your distributor has a vacuum canister on it, that means it is NOT a marine distributor. And marine carbs do not have a vacuum hook-up as marine engines do not use it. Vaccum advance is there for auto use to advance the timing when the engine isn't under heavy loads to improve the economy. In marine applications this is not needed as a marine engine is always under full load at every given RPM point. You have just confirmed you have a truck engine in your boat. The next thing I would look for is a marine distributor to fit your engine as automotive distributors do not have flame arrestors in them to prevent sparks from igniting any fuel vapors. I would reccomend you get a timing light and set your timing to around 24-28 degrees total timing.