engine dying out!!!

[da-greenboater]

Just recently purchased and semi-restored a "PROJECT BOAT"! (1978 Bonita w/ mercruiser 140). Had lower unit installed and head work done (warped) to make boat functional. Took boat out on the lake experienced some misfiring and bad idling. However, I contributed that to the bad gas that sat in the boat prior to the work being done. Anyway, ran all the old gas out of the unit and refilled with the highest octane, only to find the boat running great for a period of time to die out suddenly as thou I ran out of gas. Refilled tank and found restarting almost impossible. Upon further inspection found out I didnt run out of gas after all. Some other culprit was at work. Pulled plugs and found some light water condensation in 2 cylinders. Can someone PLEASE offer this novice green boater some possible insight and remedies to my dilema!?!? signed the PROJECT BOATER...

 

[sculbert]

Re: engine dying out!!!

Two things you need to look at. Your manifold is a split manifold and they have a few layers of components called water jacket covers that deteriate and start leaking. The is the unit your carburator is sitting on. You will need to make sure it isn't leaking. <br /><br />The cutting of issue sounds like it might be a bad ignition coil. My experience is they seem to go bad alot. I have two of them in my basement. That could be your for cutting off after running for a short time.<br /><br />check the ohms resistance of your coil from the tower point to the - terminal test the resistance. You should have over 10,000 ohms if your coil is a external resistor coil and 7700 if internal resistor. It should day on the side of the coil. If you have 12 volts on the + terminal it should say internal resistor. If you have 7 volts it should say external. this is very important.