150 johnson scored cylinder

[greg2767]

What are my options on repair for an engine that has scored one cylinder. Would this engine run for a season if I honed the cylinder and put in a new piston. The one mechanic I took it to wanted to completely rebuild with boring and new pistons for $4,000.<br />Greg

 

[Dave Abrahamson]

Re: 150 johnson scored cylinder

You can do one piston at a time. The weight of the pistons will be the same. You could also hone and re ring the other pistons at the same time as long as you got it apart. The important question is why it scored the cylinder in the first place. Has that been fixed?<br />You also might want to keep this all in one thread..it gets confusing sometimes

 

[Paul Moir]

Re: 150 johnson scored cylinder

In the other post he mentions other cylinders being rusty from exposure. I'm worried about the crank & bearings not far behind them. All of a sudden $4000 doesn't seem unreasonable...<br />But please understand Greg, I know next to nothing about your engine. I just thought that needed pointing out.

 

[Dave Abrahamson]

Re: 150 johnson scored cylinder

Paul knows more than I,(or most on this board for that matter), I would heed his advice. I'm a backyard hack at best.

 

[rodbolt]

Re: 150 johnson scored cylinder

depends on why it failed. you have to finnish the dissasembly and inspect the crank,rods bearings and exhaust divider as well as the block for excessive corrosion. after honing,not really reccomended. the bores MUST be measured in 9 places each and the egg and taper recorded and cross checked for the maximum piston to wall clearence. while a one piston rebuild is doable not many can do it correctly. the only way to know is a thourough inspection of all the parts and a complete inspection of the bore and the actual piston skirt measurements to insure a correct piston to wall clearence. if its at the max or over you will see a lack of idle quality and a shoet engine lifespan. what you can get away with on a tinymite motor just wont work on a 150. the operating stresses are much different.