Piston Scoring

[JimmyT]

Here is a pretty good article from Madsen's on piston damage. Click on the link below: https://www.madsens1.com/copy-of-rod-bearing-failure-on-pro-saws

 

[cwballistics]

I just received a non running 038 super. It turns over, but has no spark. I’ve already bought all of rubber and a new carb to replace right off the bat, and hoped I would try and get it running before I go tearing it apart like I am prone to do. I am satisfied with the super, but like many, I am looking for a reason to throw a magnum p and c on it. Here are the best pics I could get. I read the above article, and it seems the damage resembles overheating/lean. What I really need to know is your opinion on the pictures. Is this an automatic replacement, or should I continue with the plan and just try and get it running and see how she goes? I know I could always stick with the plan and upgrade later, but if it’s a definite switch out, I’d rather just do it all in the beginning. I know if v/c tests fail, I’ll be tearing her down, but I won’t know that until next week. I guess the real question is, can I spend this weekend shopping for a new jug and piston?
Thanks

 

[Wood Doctor]

The v/c tests will fail but you do not even need to conduct the tests. It's "an automatic replacement". First two Pics reveal it. Rebuild the top end. The saw is worth keeping.

 

[cwballistics]

I’m new to this, so bear with me.
How can one tell that the v/c test would fail just from looking at those pictures? I’m trying to learn all I can. Thanks

 

[irhunter]

My 2 cents. Based on the pics, you will want to pull the cylinder and see more fully what's up. I would not buy parts before that. You won't know, fully, what you might want.

But...I would P&V test before the cylinder removal. The pre-tear-down test provides useful intel. Once you have the carb and muffler off...a test takes...a couple minutes.

Making a plan knowing what caused the damage is nice.

Roy

 

[cwballistics]

I can’t help myself. I just scored an oem jug and piston kit off chainsawr in “good used condition.” Piston looked good, but no pics inside cylinder. I left a note saying that if there was any scoring, for him to contact me before processing the order.
From reading on here, they seem to be well trusted, so I took a chance sight unseen.
This might be a stupid question, but should I get caber rings or go with NOS OEMs, or just wait and see what they look like?

Thanks

 

[irhunter]

should I get caber rings or go with NOS OEMs, or just wait and see what they look like?

Thanks

Well, based on the pics, you will want new rings...

OEM or real Caber...either is fine, I say.

BTW, I imagine you will be able to sell your old cylinder.

Roy