Chain Binding Up Problem

[buckwheat]

Help me out, guys. I decided to go down to a 16" bar from an 18" on my 026 (Walkerized). I picked up 3 loops of Oregon chain off of eBay: full chisel 3/8", .050, with the bumper drive links. There is a "72" on the drive links. At the same time, I picked up a 16" Stihl Farmboss laminate bar at the local shop (I was in a hurry), clearly marked 3/8", .050.

So I take it out to the job and everything is cutting great for about 10 cuts. Then things just appear to bind up with the chain not moving through the bar. I switch to a new loop, and the same thing happens.

It appears to be oiling OK. The 18" setup was a GB solid bar with Sabre chain, same specs, which worked fine for years.

Anyone else familiar with this? Is there a chance I got the wrong guage? Is it possible that the tolerances are so tight that the bar rails are expanding? Any ideas?

 

[Locoweed]

Do you have a 3/8 sprocket on the saw?

 

[skwerl]

Is the bar the newer 'reduced oil flow' style with the tiny oil hole? Does the oil hole line up with the oil output hole on the saw? One of the reasons I quit running Stihls is the reduced oil flow. My Huskies gush in comparison and oil is much cheaper than bars and sprockets.

If the oil hole in the bar is the new tiny angled style, try drilling it out. I have a set of DeWalt pilot point drill bits from HD and the 3/8" bit works perfect for drilling out the oil hole. As soon as the pilot point punches through, you're done.

Another option is to use a thinner bar oil so it flows faster.

 

[manofstihl]

check sprocket

Make sure your bar and sprocket are 3/8 gauge- 026's came new as 325 saws- binding could be a bad bar, even if it is new- (it happens0 do not waste your time drilling out oil holes, I was respnsible for a fleet of Stihl rental saws for years and we never had any issues. as long as your saw throws a line of oil when you run it is oiling enough. look at your chain links and see if they areburred or beat up, signs of a sprocket or tension problem.

 

[RaisedByWolves]

Sprocket???

Oil problem or chain simply too tight to begin with = hot bar--->

 

[Dadatwins]

Worn sprocket/bearing, bad oiler/not enough oil /misaligned oil hole, chain too tight, wrong gauge, poorly made chain/ bent drive links all could cause what you describe. If all gauges are the same, Start by running the new chain around the bar off the saw and make sure it flows easily with no binding. Next check the sprocket and bearing to make sure they are not worn. Should be easy to diagnose, if the sprocket is loose on the bearing, replace it. Good luck.

 

[Lakeside53]

as the last three replies have said......

Also, there's NO problem with Stihl bars and oil hole sizes... and particularly on the 026 - that saw liternally drips oil everywhere... and the bar is the same type as all the others with the 3003 tail - up to MS660...


...and check your oil tanl vent... if the oil reduces over time, then it can be your vent not allowing pressure to equalize.

 

[Dale M]

Hi. Im new around here and this might not be your problem but my Husky was doing the same thing, with a new bar and chain, thought I had it too tight.. The chain would stop turning as soon I Let off the throttle,, My clutch bearing was shot,, when cleaning the saw i used a spray degreaser and washed out all the lube in the bearing, and it would get hot. expand and just grab onto the clutch drum,, . I put in a new greased bearing and all is fine..

Dale M

 

[buckwheat]

Thanks for your replies fellas. After having a chance to look at it, without being able to run it this time of night, I think it is the new chain. The sprocket is the same one I've been running with the 18" setup, which is all the same: 3/8". .050 guage; and the oiler appears to be working.

Spinning the chain by hand on the saw with the new bar feels a bit tight compared to the 18" GB/Sabre. Comparing the two loops I used today with the one I didn't use, I noticed wear on the sides of the drive links where there appears to be a kind of anodized or painted finish. It might simply be that I had the chains too snug, and without sufficient break-in, it generated enough heat to cause it to bind. Fortunately, there is no blueing on the bar rails.

I'll try running it with the chains a bit more loose until that anodizing wears off; and I'll probably end up ordering another GB bar, which I should have done to begin with. If that doesn't do it, I'll look further with some of the suggestions given here.