Is my cylinder toast ??

[onelugnut]

I just pulled the cylinder off my new to me 87 js 550. It would not stay running running so I figured I would start from the ground up. I found this nick at the bottom of the port, The cylinder walls look good as far as scratches go. Sorry if I didnt post this correctly

 

[badboyr6]

doesnt look pretty to me..

 

[onelugnut]

doesnt look pretty to me..

Are you trying to make me cry LOL

 

[FlightPlanDan]

It may not be that bad ....did you check compression on both cylinders b4 you tore it down?
It doesn't look happy, but a js550 has likely seen some ride time.

 

[onelugnut]

It may not be that bad ....did you check compression on both cylinders b4 you tore it down?
It doesn't look happy, but a js550 has likely seen some ride time.

I did check the compression about 155 both sides. I tore it apart to replace the seals. I the nick is at the bottom of intake, I may just run it as is for the rest of the year.

 

[badboyr6]

if its running, then it may be still good to run. i was looking at the nick, and as long as it doesnt snag a ring, you should be ok

 

[SUPERTUNE]

That's not bad enough to be a problem as long as the crank bearings are good. measure the piston to make sure it's the same as the other piston. (within .001)
Keep in mind when doing a crank reseal on these old 550/440's engines, use only OEM Kawasaki seals and don't buy the front seal, then buy 2 of the rear seal (one that's next to the crank bearing) and use it for the front seal.
This gives you a double lip seal to replace the single lip seal that's always been a problem with crank seal leakage and failure for 550/440's.

 

[onelugnut]

Thats good news : ). My manual is on the way.
When I measure the pistons do I just mic them from side to side at different areas?
One of the pistons has a nice gouge in the side, I think I will replace them.
I am always looking for good tips

Thank you guys for the help