Hi there, A while back I posted about an issue I had with my chain not turning, even when trying to manually turn it. Wasn’t sure if it was chain, bar or what. I cleaned out the bar guide grooves, greased the nose sprocket that wasn’t turning, put on a new chain and all was honky dory until this past week. I was cutting an ash log and when I completed the cut the chain popped off. When I went to take the cover off to replace the chain I noticed the nuts were really loose. I tried to put chain back on and it just wouldn’t work. Inspected the chain and I noticed the teeth were nicked and burred. so definitely user error here. I hadn’t checked the chain tension or the clutch cover. I will replace the chain. Maybe the bar. But I also want to make sure this isn’t possibly a sprocket issue as well. Here are a couple pics...looks fine but one of you guys might know better.
Yup. Check the drive links on the chain. If the chain jumped it hit the bar and made tiny and i mean tiny dings in the drive links. Enough to bind and stop rotation. My Stihl 194T has a spur type sprocket and not the rim type like yours. Carefully inspect each drive link on the chain and hit it with your flat file (i used the one for my rakers) and 2-3 passes and walla it worked. I had the bar off and slowly pulled the chain along slowly pulling each cutting tooth to see if there was any resistance for the DL below and if so i checked and filed as needed. Also eyeball the chain when pulled taught and see if any links are bent. Check bar groove the same way. "Luckily" it was only a 12" chain on my saw. Its a rather tedious process and id rather sharpen a 36" chain. Ive had a chain jump numerous times over the years but a first for this. Bent one good once when the saw bound in the cut and i wiggled the hell out of it to remove and in turn bent it!
Hard to tell for sure, but it looks like some chips off the casting, maybe a small crack too For the $7 or so, I’d replace it. That’s on your 550?
Yeah it’s the 550. Are these things tough to replace? yeah thisis 18”. I’ll give it a go. It’s not like I have a busy Christmas
I'd say the drive looks good. I have grooves wore into some of mine and the still run. I have replacements sitting on the shelf if they start giving me problems.
