Chainsaw Sprocket Wearing

[jstutz]

I let my buddy borrow my chainsaw and he called and said it was skipping. I have not felt this before but when i took the cover off and looked at it, the drive sprocket was very worn. This is a Poulan Pro 4218. No a pro saw by any means but it does what i need it to around the house. I ordered a new sprocket and put it on no problem. I ran the saw for about 5 minutes and checked it out. There is already small wear nicks on the corners of the sprocket.

Is this normal? How often do these go bad. The sprocket that i took off there was about three years old. Could a bad chain or over tightening the chain cause this? I dont want to ruin the new sprocket and im concerned because i have read posts where people say then never change them or they should last 10 years or more. I know the Poulan is a cheap saw so i dont expect super long life. Any advice will be appreciated.

 

[Bluestream]

They don't last all that long, as its mostly metal on metal even with the chain oil. It should last for you to use up 2-3 chains as they wear out.

My saw goes through about 7 chains to one sprocket. And I keep my chains way longer than I should because I'm cheap...

 

[MolaKule]

A few possible problems may be occurring:

Saw guide is pinched in one or more places causing undue drag,

Oiler pump bad or not enough oil being supplied to chain,

Wrong or improper lubricant,

chain tensioning too tight,

improper chain type.

 

[jstutz]

Cool, How do you know when a chain is bad? I have never replaced one. I do a light sharpen after every use and it stays sharp and cuts great. If it did wear out, i dont know that i would know. What happens to them as they wear out? From what i see online, you can get tight spots but thats about all i see.

 

[jstutz]

Originally Posted By: MolaKule
A few possible problems may be occurring:

Saw guide is pinched in one or more places causing undue drag,

Oiler pump bad or not enough oil being supplied to chain,

Wrong or improper lubricant,

chain tensioning too tight,

improper chain type.


Thanks, Well going down the list, if its my fault, it would most likely be too tight of a chain. I mostly use Husqvarna bar oil and always some kind of bar oil. The chain rolls nicely around the bar, the chain is the one that came with the saw, oilier uses about even with gas which i think is about correct. This pretty much leaves tension. I have let a few people borrow it and i know they dont know much about saws so who knows what they did to it( not purposely). I also , after read a bit today, probably ran the chain too tight. I was just surprised to see nicks already. Very small but i could feel them with a finger nail. Could the current chain be ruined and scoring the new sprocket?

 

[Loobed]

G-Oil had a free after rebate deal for bar and chain lube.

 

[doitmyself]

Originally Posted By: jstutz

Could the current chain be ruined and scoring the new sprocket?


Chains can also stretch. They get a tiny bit of wear on each rivet and that can add up to a lot of stretch. Now you have a stretched chain riding on a sprocket designed for the a certain sized drive link.

Having said that, I have never had this problem with high quality chain, bars, and sprockets. Like said above, a sprocket should last through 6 to 8 chains.

Inspect your chain very close. Feel for stretch. Look at the individual drive links. Look at the bottom of the links (ride along the rail) for unusual wear. Do the same for your bar, because the rails can wear uneven also, which will affect a new chain.....which will affect the new sprocket......around and around it goes!

I imagine youtube has demonstration of this stuff. I rarely loan chainsaws anymore due to obvious reasons.

 

[cchase]

It seems to me that a sprocket should last many, many years. We have saws that are 35 years old and older with original sprockets. The saws aren't used daily but do have a LOT of hours on them.