Posted by mannyc [173.245.52.194] on Monday, April 05, 2021 at 21:52:49 :
greetings. I have a 1940 wood Matthews sedan cruiser. it was repowered in the late 1990s with 454 marine power carburetor equipped engines with mechanical fuel pumps. They have proven super reliable. Every year we winterize the engines, change the oil, change the oil and fuel filters and fog the engines. we flush the engines with pink antifreeze. every spring we open water valves, start engines and are good for the season. this year (today) we readied the port engine for starting. we cranked the engine, it started after a few revolutions and fluid started misting out of dip stick tube - dip stick was in. Upon checking and rechecking, the crankcase had gasoline in the oil. I drained the oil and gas and am now trying to figure out how this happened. I suspect the fuel pump somehow allowed fuel to flow past the diaphragm into the crank case. The fuel tanks are situated so that the engines self prime. I do not know if gm marine 454s are like dodge inline sixes in that a bad diaphragm will allow fuel into the crank case. can someone here with knowledge of gm engines assist? I removed the fuel pump and will replace with a new quality replacement. I will also replace the clear tube that returns fuel to the carburetor as it was brittle. Can someone here assist? thanks. mannyc
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