Help Identifying Piston - '86 Merc 150 XR2

[hsdtech]

I'm trying to find out the make and size of a piston in my 1986 Mercury 150 XR2. It's hard to make out the info on top of the piston, but looks to be;

3209 HE29

"S" with maybe 3 letters above...This not an OEM piston.

 

[Faztbullet]

Re: Help Identifying Piston - '86 Merc 150 XR2

Look to be a old Wiseco and its .015 oversize as its stamped on the flange of your block...(2nd picture). You can measure the bore to insure correct size, from the looks of piston/cylinder you have a carb or ignition problem.