Help - 112 Johnson rebuild / sleeve questions

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Once you take the motor apart and measure all 4 cylinders you can make that decision. The important thing is if the crank is good. You can resleeve but it's expensive. If the crank is good then you could bore all 4 and basicaly have a brand new powerhead. If in fact only one hole needs boring, then by all means do it that way. Keep in mind the pistons wear also. Be sure and use a good brand of piston like OMC or Wiseco. Both are good but have specific paramiters. Your final set up will dictate whether you use forged or cast pistons. Let me know how you make out. Good luck!
 

fishy

Recruit
Joined
Mar 18, 2001
Messages
3
Help - 112 Johnson rebuild / sleeve questions

I bought a boat with a Johnson 112 Special(1994)with a frozen powerhead. It had a head gasket leak and stuck the top port piston, the owner sprayed all cylinders with WD40 and it sat for 2 years. I took the head off, and with a wood block unstuck the piston (motor now turns over) but there are minor pits in the top of the cylinder. Rebuilt heads run from 1400 to 2500, so I will probably rebuild this one. Should I bore all the cylinders and replace all the pistons (other three cylinders are good, no scratches or scoring)or just overbore this one? I don't like the idea to just bore one (one larger bore) but I hear that is OK, and the costs of 4 pistons is high. Could I get this one resleeved and buy a standard piston for this cylinder at a better price? I was just going to re-ring, replace all seals and gaskets, and replace top & bottom rod bearings. Any opinions from others who have been there? Thanks!
 
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