Force 40hp, loosing one cylinder.

[backyardangler]

1995 40hp, has been running like a Singer sewing machine after this years rescue and rebuild. Will run about ten minutes and then one cylinder drops off. Happened first last weekend, one cylindered back about 10 miles. Thought it was a plug wire, nope. Plugs check good. Thought the plug wire was not connected at the distributor, seems good. Did it again tonight.

I have just mounted a transducer at the transom, not far from the motor. I noticed it throws water up against the bottom cowl of the engine. When it quit tonight, there was water in the bottom cowl. Any ideas? Can a little water flood out a coil? As I raise the engine and pull the cowl off there is about a half pint of water.

Thanks in advance all.

 

[pnwboat]

Re: Force 40hp, loosing one cylinder.

Yes water can short out the plug. I had a similar problem when I mounted a fish finder transducer on my boat. Threw up a rooster tail higher than the motor. Turns out there is kind of a hole or gap between the transducer body itself and the part of the bracket that is screwed to the transom. I had to make a metal plate out of aluminum to cover that area where the hole or gap was. Mounted the metal plate under the bracket for the transducer. Used the screws that secure the bracket to the transom to also hold the plate in place. Fixed the problem. See attached pictures.

 

[backyardangler]

Re: Force 40hp, loosing one cylinder.

Thanks for posting those pictures. My transducer is exactly the same. Thats a great fix, I'll give it a shot. You probably just saved me $300 bucks.

 

[backyardangler]

Re: Force 40hp, loosing one cylinder.

Follow Up: Finally got a chance to run the boat tonight. First I started the boat and had both cylinders, so it felt like something dried out. I removed the transducer, which eliminated the rooster tail hitting the cowling. I ran the boat WOT for 45 minutes and could not duplicate the gripe. So I guess that stupid rooster tail was flooding out my plug. Who'd a thunk it. I'll make a bracket like pictured above. Thanks again to everyone for the help.