Check to make sure it has the correct chain on it. The chain on the clicky one could be stretched out also. I’m not saying it’s not the spur, but I’ve seen a lot of them that are worn completely through to where the sprocket will fall off
3/8 pitch picco chain with the "p" symbol on it. Another gas "6" on it. I believe there are quite a few chains for that saw but it matches the sprocket that says 6z picco as well with 6 teeth. I'll double check with the owner too. The sprocket on the working saws matches the sprocket from the snapped saw. They all say 1137 /01 and z6 picco. I think I figured it out - the grooves are made from the two pieces that connect each link of chain and the raised piece is formed from wear because there's a gap right in between those two pieces. Just filtered the old fuel in there and it sure was yummy.
Probably a crap load of chips in the oil reservoirs too. Work saws that are not yours are so abused and neglected.
Checked the spark arrestors on the 2 almost-ready-to-go saws. They both need new spur sprockets. Ordered some Stens ones on eBay. I did take one slightly used one and install it on one of the saws. Now it doesn't make the noise it was making. Also checked the plugs. One saw needs a plug and the other one has a new one. Ordered 4 of those on eBay too - NGK CRM6H. The one that needed a plug had a lot of crud under the boot of the spark plug. Yuck. Replaced the sprocket on the right with the sprocket on the left. Plastic needle bearing looked alright. A dab o' lithium grease. The new Stens sprockets come with a metal needle bearing. Spark arrestor not bad but brushed it clean. There was more carbon buildup on the spark arrestor cover on both saws than on the spark arrestor itself.
Got the sprockets, needle bearings, and new spark plugs and put one new sprocket/bearing combo on along with 2 new spark plugs. Tested out the saws and they seem to be running pretty good. This sprocket still has life. Just ended up brushing it clean and lubing up the bearing with some lithium grease.
