Yellow 587 top end rebuild advice

[tregger]

Hello all,

I acquired a 90 SP with low compression. I'm not trying to restore it to perfect condition, just some practically free summer fun.

I am planning on going with a top end kit from WSM. Both cylinders look to be glazed, but are not gouged or scratched.

Do people have good luck with just a flex hone and standard sized pistons? My (cheap) micrometer reads 75.8-76 when I measure the bore across the top.

This is just a project for fun/learning, I am not looking to increase performance, just looking to get compression above 120.

Looking forward to any advice

 

[mikidymac]

You can't accurately measure the cylinders with a caliper, you need an actual bore gauge. Take the clearance specs to your local machine shop and have them measure them. If they are within spec then yes, just a ball flex hone is fine for new pistons and rings.