20" tsumura light bar, tip locked up after 3 hours of use ???

[ken morgan]

so i bought a 20" tsumura off of fleabay new. put it on the 372 and after about an hour of cutting some 30" elm with a dry center I noticed the tip started smoking.

the wood was kind of pithy in the center 4" or so but never had an issue with my oregon bar and this. so I grabbed my sprocket greaser and greased up the front sprocket checked to make sure the saw was oiling and after about another hour it was doing it again. greased it again and it locked up at the three hour mark. since I did not bring a spare bar i finished up with the 346 and went home for the day.

got home and the sprocket would not move at all. thought maybe the fine crap from the pithy center had caked up the sprocket bearings or something so i dunked the bar in the parts cleaner and let it soak overnight came back out the next morning, blew it dry, relubed the sprocket and still no dice. could barely turn in with a shim slid into it. chain was fine, the guide rails up to the sprocket were fine, just the sprocket was locked up....

anybody got any suggestions?

 

[nighthunter]

Did you experience a kick back with that bar, bearings could be out of whack cause of it

 

[ken morgan]

Did you experience a kick back with that bar, bearings could be out of whack cause of it

nope, smooth cutting the whole time and chain, while gunky had lube on it. we were using peavey's to get a clean cut as the Japanese members of the crew were ooh-ing and aww-ing at Carl Millers port work and the awesomeness of its chip throwing powers

 

[ken morgan]

From Scott via PM....

Hey Ken , many years ago I had a tip lock up cutting up a punky (heart wood rotten) Chinaberry tree . I was 19 miles from home so I borrowed a empty coffee can , took the bar and chain off to wash out all the fine dust/goo out using fuel mix . Then I used bar oil to relube the bearings . I have never used grease on a sprocket tip .

I have a old carb cleaning kit (caustic soap type) that I use to clean carbon off of plugs and cylinder heads . I would soak my bar tip in the carb cleaner for 15 minutes if the mix didn't free it up .

Scott

 

[Sepia]

How tight was your chain when the sprocket locked up. How hot was the sprocket tip? Perhaps running with the tip buried for extended lengths of time allowed fine dust to build up around the sprocket tip area and cause the chain to tighten and overload the sprocket bearing.

 

[blsnelling]

They do sell replacement tips.

 

[Marley5]

I'd be a little upset, glad you had the 346.

Out in the field,I would just walk the saw across a log at wot, always cleared.

And I was in the Market for a new bar.

 

[rupedoggy]

Tsumura, isn't that Japanese? Why not buy local instead of the internet? Then you could return it. Sometimes it isn't worth a few yen saved.

 

[Sepia]

Tsumura, isn't that Japanese? Why not buy local instead of the internet? Then you could return it. Sometimes it isn't worth a few yen saved.

The O.P. is in Japan

 

[rupedoggy]

I know that is why I posted what I did. He could buy the Japanese bar in Japan, right? If you wanted a Sandvik bar, made in Canada, would you send to Japan for it?

 

[Sepia]

I know that is why I posted what I did. He could buy the Japanese bar in Japan, right? If you wanted a Sandvik bar, made in Canada, would you send to Japan for it?

I'm kinda slow so it took me a bit of head scratching and re-reading of the original post to see what you are saying. Assuming the ebay seller wasn't in Asia, I see your point now.

 

[ken morgan]

How tight was your chain when the sprocket locked up. How hot was the sprocket tip? Perhaps running with the tip buried for extended lengths of time allowed fine dust to build up around the sprocket tip area and cause the chain to tighten and overload the sprocket bearing.

neither tight nor loose, as far as how hot??? it was smoking so hot enough would be my guess the tip was never buried for any serious length of time, at least no more than any other bar I use.

 

[ken morgan]

I know that is why I posted what I did. He could buy the Japanese bar in Japan, right? If you wanted a Sandvik bar, made in Canada, would you send to Japan for it?

actually thats the problem its not that easy to acquire in japan, and the price is actually higher. they maintain high prices over here as there is no competition...you either buy stock parts form a dealer, (at great cost I might add) or pay roughly the same price for aftermarket. thas why I buy all my stuff from the states, its cheaper even with the price of shipping. It might surprise you to know that when the 365/372 was selling in japan it was over 1900 USD for one. Funny but you can buy Makita's cheaper in the states then you can here... that why lately there has been a bunch of folks selling the mid grade ranchers or stihl farm bosses on yahoo auctions at a pretty reasonable markup... just couldn't abide with the plastic cases.

 

[Czed]

Not defending them but I've run total/tsumura since the 80s and have had excellent use out of
Them.
Bad one maybe?
who knows
Have you tried the customer service route?

 

[pioneerguy600]

Ken, did you grease up the tip before running it? If not then it likely filled up with fine dust and that stuff mixes with whatever oil was in there plus the chain lube and makes a mix that will jamb up the little rollers the tip spins on. You have to get that gunk out somehow so its either soak the tip for a long spell and keep blowing the softened crap out or bite the bullet and remove the tip.

 

[ken morgan]

Ken, did you grease up the tip before running it? If not then it likely filled up with fine dust and that stuff mixes with whatever oil was in there plus the chain lube and makes a mix that will jamb up the little rollers the tip spins on. You have to get that gunk out somehow so its either soak the tip for a long spell and keep blowing the softened crap out or bite the bullet and remove the tip.

yeah I did, but I got it unlocked this weekend, it just took multiple tries at forcing grease through it to push the crap out. it spins fine now. Had me worried for a while there

 

[pioneerguy600]

Whew, great luck, that punky wood can jam the heck out of sprockets. Best to continue with the grease now as the chain oil won`t be able to get down around the rollers any more.