Seized Bar Sprocket?

I have a Husqvarna 450e, 18" bar & hogged off a 16"-17" oak stump. The saw struggled as the cut finished. When I tried to knock down an adjacent 2" Beech, the chain would not turn. After troubleshooting, it appears that the sprocket has seized up, almost solid. It will turn, reluctantly, with some light percussion persuasion, but barely. The chain seems to be adequately oiled.

What did I do to cause this failure? The saw gets run 1-2x per week for about 1 tank of fuel & bar oil each time. Any advice/ input is gratefully sought!

 

Probably nothing you specifically did. Could be some chips or something got rolled in or the bearing could have just failed.

 

Take a flat screw driver and pry the tip of the bar rails apart a little to see if this frees up the sprocket. Pretty easy to pinch the nose of bar to where the sprocket won't turn freely...

 

Could be packed with chips and needs to be cleaned. Scrape out the groove and make sure the oil tunnel is clear. Use compressed air on it. Hose the sprocket with wd40 and roll the sprocket back and forth on a wood surface to see if it will loosen up. Lay the bar on a flat surface to see if it’s bent. Sprockets fail, tips get smashed, bars get bent, grooves and rails wear out. Sometimes you have to get a new one.

 

Chips or a sliver of wood jammed in there , I have had that happen and had to put the bar in a vise and tap the sprocket around and it eventually freed itself up.

 

If this happened during stumping, I agree with carefully inspecting the space between the rails. Could have pinched them together a little. Can you post some good close-up pics? Packed chips is also a good culprit. Compressed air might help in that instance and a larger zip tie cut at an angle to dig out the wood.

 

As has been said , likely wood chips wedged in the nose of the bar . I take the saw ( not running ) and put the nose of the bar on a log with some pressure ,and move it back and forth . If it is stubborn , flip the saw and repeat . Has always worked . Lube bearing afterward .

 

easy fix, follow these EXACTLY or it doesn't work...

Step 1: Disconnect your oiler on the saw
Step 2: Fill saw with gas
Step 3: Start saw
Step 4: Run it like hell to get the bar REALLY hot
Step 5: Wood chips start to smoke, then burn, then turn to ash
Step 6: Spocket now turns freely
Step 7: Profit



Your mileage may vary.

 

Thank you for the great advice! I will play with it after work .

 

Easy peasy

 

After spending 1/2 hour tapping the sprocket through a few full revolutions, it is still very stiff. I am now ready to try Joe P's suggestion.

I need a recommendation for a 7-8 hp saw that will take this bar. I do not think the 3.2hp of my little 450e will be enough to spin the sprocket fast enough to burn up whatever is jamming it.

 

Toss it in the fireplace overnight

 

If the chain doesn't spin free, you risk smoking your clutch. Did you try pushing grease through the tip hole, or does it even have a grease hole @ the tip?

 

How did you make out? I commonly get chips stuck in mine. Could have pinched a bit. Above advice X2.

 

My suggestion was more tongue and cheek than an actual course of action. Disconnecting the oiler is gonna make a hell of a mess. Try KROIL, it is my go-to for un-sticking stuck things or greasing the sprocket as suggested earlier.

It's possible the bar is just used up and ready to be replaced.

 

If it ridden hard and put away wet then this is a good possibility too.

Good looking pup in the Avitar JoeP.

 

thanks!! Wife caught us napping on the couch when she snapped the picture. Probably 3-4 months after we adopted him from a kill shelter.

 

Those make the best pictures

 

I won't buy ANY roller nose (sprocket) guide bar without a grease port in it. No exceptions. Actually, I prefer a replaceable roller nose for my larger saws. They get greased before I use them every time and I've never had issue one with the sprocket nose binding up.

Your mileage may vary but I know what mine is....

 

Thats a cheap bar, grab another one. Im all for fixing replaceable things, but that tip is smoked. It happens, especially on small cheap bars. I've done the same. Its pretty obvious when it is binding inside. If you think there is hope, spray the tip down with oil... but its just like a rod bearing. Once they go, they are gone.