burning a piston?

[nhrobalo]

'88 merc 60hp 3cyl

Put new plugs in it runs perfect for about a mile then drops #1 cyl.Take out plug and there appears to be metal splatter on the plug that shorts it out...Am i burning a hole in the piston? thanx...........scott

 

[erie_guy]

Re: burning a piston?

Certainly sounds like you have a piston that is overheating and perhaps melting. It may be caused by: an overlean carb., lack of lubrication, or a cooling problem near #1. I suggest you do a compression test and report on the numbers and try to look in the cylinders with a boroscope. You might be facing an upper teardown. Sorry . . .

erie_guy
Port Clinton, OH

 

[nhrobalo]

Re: burning a piston?

compression is 120+- on all 3 cyl (no hole yet) trying to get a pic inside cyl (dont have access to boroscope) any ideas how to get a pic in there?

 

[erie_guy]

Re: burning a piston?

Harbor Freight has an inexpensive scope that will let your eyeball see inside. Other than that - can you verify that #1 has fuel flow (fuel in carb) or if it is running dry? Check for ring scrapes on cylinder walls, melted pistons, and trash in the cylinder bore. Keeping my fingers crossed that you can discover the problem before it craters.

erie_guy
Port Clinton, OH