Got the free boat with non running 3cyl blues. Brought her home started to check If motor was worth fixing. Compression test 140all, weak fire- replaced stator and trigger, power pack ok, new starter, paid for water pump and lower gear oil and new fuel pump kit(supposedly installed.) Electric choke solenoid missing(NLA Part). Have much time and money invested. Presently will start if primed directly into carbs,didn't stay running until I put gas tank up at carb level(they replaced vacumn hoses and diaphragm something still not right!) but now after priming and with gas tank elevated will start and run ok and restart without priming. No bad running noises. The water pump was correctly serviced? I am not seeing water stream from discharge hose. I read or heard that the three cylinder mercs top cylinder often heated up and died and that the fuel pumps were sometimes modified to improve function? At this point wondering if I should give up?? Anyone know this model motor? Was this a poorly designed model?(2 carbs 3cyl) I can redo water pump and fuel pump and flush out cooling jacket(maybe water pump pieces) or try to sell it as is for the $500 invested and repower? Seems strange that it heats up even with pressured Flush ears attached!! Just an old motor but would use if I could. Thanks for help.
. Good luck.