Is my chainsaw drive sprocket bad?

[fire_man]

I was replacing my worn chain on a Husky 455 Chainsaw and noticed the sprocket teeth look gouged. Does this look like it needs to be replaced?

 

[claydogg84]

Not yet.

 

[fire_man]

Those grooves are normal or just not bad enough yet?

 

[claydogg84]

Those grooves are normal or just not bad enough yet?

You're going to get some wear there eventually. It's not bad enough to worry about yet.

 

[dougand3]

Normal wear, yes. Not bad enough yet. When it starts to make a trough and chain starts to travel a shorter circumference, time to replace.

 

[fire_man]

Thanks for the replies. How do you get it off when it's time? There is no obvious retaining nut.

 

[dougand3]

Here is a BAAAAAAAD sprocket.


Take a pic of your clutch. It's probably like Poulan and there is a tool to rotate clutch CW. Search Poulan clutch tool. Impact hammer works the easiest. Although you can bush league it - rope in plug hole, Saw in corner hemmed in, big flathead screwdriver being whacked with hammer.

 

[fire_man]

Doug

Thanks for the pic. Now I totally understand what a bad sprocket looks like. The chain must have been skipping like crazy.

 

[dougand3]

The chain must have been skipping like crazy.

It was a 52 DL bar and you couldn't tighten chain enough to use it. The previous owner just went and bought a 50 DL chain loop and continued to run it. It was so grabby and stuttering with the 50 DL chain by hand pulling, I was scared to even test it.

 

[fire_man]

Hard to imagine someone would change the chain to make up for a worn sprocket.

I just found this in the owner's manual for a 455 Rancher. Seems kind of crazy to change it every time you replace the chain.

Regularly check the degree of wear on the drive sprocket.
Replace if wear is excessive. Replace the drive sprocket
whenever you replace the chain.

 

[Oldman47]

Nominal life per my Husky manual is supposed to be about 2 chains per drive sprocket, but I keep swapping chains for sharp ones when I am doing a lot of cutting. Rather than wear one out I gradually wear out all 6 but that means I need to ignore the x number of chains per sprocket. Replacing a sprocket on a Husky means removing the clutch to gain access. A Husky clutch is outboard of the drive sprocket.

 

[claydogg84]

Replacing a sprocket on a Husky means removing the clutch to gain access. A Husky clutch is outboard of the drive sprocket.

Not all Husqvarnas are like that. My 455 was, but my 372XP isn't.

 

[fire_man]

My Husqvarnas EPA II 455 manual makes no mention of a drive sprocket replacement interval. But some other 455 manuals say to replace after every 2nd chain. They must use harder metal in some of the sprockets??

I've been through at least ten chains over the years on the same sprocket.

 

[Bigg_Redd]

Does this look like it needs to be replaced?View attachment 159716

No

 

[Jeffm1]

Thanks for the replies. How do you get it off when it's time? There is no obvious retaining nut.

Look on YouTube.

 

[Oldman47]

When you are ready to replace, this video will help.

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Note that the guy uses a chisel where I would use a punch and gets away with no restraint on the engine rotating where I would expect to be stuffing some nylon rope through the spark plug hole to keep the crankshaft from turning.

 

[fire_man]

Thanks oldman!

 

[Hoozie]

Be careful just stuffing rope in the cylinder. If the piston is far enough down, there's a (small) chance you can get a bit of rope out the exhaust. Then with a good wack you break the ring land on the piston.

There's an actual tool available to stop the cylinder to allow removal of the sprocket.

 

[Fred Wright]

That sprocket looks good. I wouldn't replace it yet. That said, I'd recommend ordering a replacement for when you do need it.

Had my 353 apart recently to replace a deceased oil pump and worm. 4 years of cutting, a bunch of new chain loops and the sprocket still looks like new. Thought the shaft bearing might be worn but it's fine and dandy too.

Search Baileys or Amazon for Husqvarna clutch removal tool and piston stop tool. Both tools will make pulling the clutch much easier without breaking anything or stuffing rope or trimmer line into the cylinder. The clutch has left-hand threads, remove it by turning clockwise. Gently.

Just a word to the wise ~ don't be a hammer mechanic with your gear.

 

[fire_man]

I guess eventually the chain will start to skip? That will not be a happy day.