1987 60 Hp Evinrude, 3 cylinders. Need advice!

[Force 120]

Hello,
Just check the compression of my 1987 60 hp Evinrude, 3 cylinders. Top cylinder 120 psi, Middle cylinder 108 psi and the Bottom cylinder 119 psi. Is it Ok for the middle cylinder low but with in 10% spec. Could I keep running like this?

 

[racerone]

Parts today are precision made.----Compression does NOT vary that much on a " good condition " motor.--My tester on a 49 cube 3 cylinder would show 135 + PSI.----I say pull the head , simple and a head gasket is really cheap for the learning you get.

 

[Force 120]

Parts today are precision made.----Compression does NOT vary that much on a " good condition " motor.--My tester on a 49 cube 3 cylinder would show 135 + PSI.----I say pull the head , simple and a head gasket is really cheap for the learning you get.

Yes, I did, and put a brand new gasket on. The middle cylinder piston wall has some mark along the piston. The top cylinder has 0.03 oversize piston already by previous owner. Just found out when remove the head. Should I bore out to 0.03" over for the rest of 2 pistons? Just for the estimation, how much should I expect to pay to bore out only 2 cylinders? The motor is still running Ok, it does not show the issues yet.