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Loss of fins

trooney

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Does loss of fins affect cooling of the cylinder to a large degree, and does it get exponentially worse if there are multiple fins missing?
 

huskihl

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I think 1 or 2 corners broke off is fine. I’ve seen 2-1/2 fins completely gone off the exhaust side run ok. They’ll run rich until warmed up and gradually lean out as they get closer to full operating temp but still 4 stroke out of the cut
 

Lightning Performance

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I think 1 or 2 corners broke off is fine. I’ve seen 2-1/2 fins completely gone off the exhaust side run ok. They’ll run rich until warmed up and gradually lean out as they get closer to full operating temp but still 4 stroke out of the cut
I bought a busted up 362C Mtron.
Solved that problem.
It should be fine. It pulls a 24" 8pin no problem in 30" oaks and base cuts around the flair. This summer I might fix it... might not.
 

Bigmac

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A few fins won’t hurt much. I would run it on my own saw, but would also disclose the fact it was going to be sold. Have seen some pretty messed up cylinders that people clam ran fine with nearly 40% fin loss. But I don’t have any extreme examples, but have a logger friend that I put a nearly new 461 cylinder, that the saw took a ride down the mountain and lost three top fins and most of the rest of the saw was garbage! Install it on a higher hour saw with a debris ruined cylinder, it runs great and has been for 2 years of hard use!
 

Czed

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I've rebuilt a lot of smashed up logger saws with a few of them
Missing 3-4 fins one missing all the pto side fins.
I'm sure they ran a bit hotter
But it never seemed to matter with longevity
Clumsy loggers usually is the end of a saw.
 

smokey7

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I don't know how much of it is true but in my mind I see fuel doing about 40 maybe 50% of the cooling.
 

huskyboy

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I had a 385 with a few missing fins, felling trees and logging it never got hot enough with the idle periods. In the winter cutting firewood it never had a problem. In the summer however, on particularly hot days it definitely overheated a little if I pushed it hard with a lot of logs laid out and no time to idle between cuts. I just compensated by tuning it a little richer. This was several fins missing though, not just one.
 
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