1989 Johnson 90HP - Is This Block Repairable? (Chipped Ports)

[CraigATL]

I've searched around and can't seem to find an answer: Our 1989 Johnson 90 broke a ring and chewed it up. Attached is a picture of what it did to the intake ports (exhaust ports have small chips but not nearly as bad).

Given that the cylinder wall is barely scratched, what would happen if we bored it out and smoothed the ports so they aren't jagged? Is it worth even trying?

Thanks!
-Craig

 

[racerone]

Should be OK with O/S pistons fitted.------This is a very common issue with these motors.-----Used blocks are not hard to find , depends on your location.

 

[Faztbullet]

Bore it .020 all cylinders, smooth and taper the chipped area. Need to replace all pistons.

 

[CraigATL]

First, Thanks for the help and info!

I was thinking of doing the following:
on the bad cylinder: bore and replace piston + rings
on other three cylinders: hone only, reuse pistons and replace rings.

What is the rationale for boring all 4 and replacing all 4 pistons?

thanks again!

 

[racerone]

It is a mistake to install new rings on old pistons.-----Not going to explain why here.

 

[Faztbullet]

Replace all pistons.....the ring groove wears and lets ring roll.