<!-- from fixya rte -->Stihl cut off saw blade won't guit turning - Stihl Ts 510 760 Cut Off Saw Repair Manual

Replace The blade.

Hi Thomas its probably had its high/low screws reset and whilst it runs fine on the bench under load its running weak try unscrewing the high screw out a half a turn

Blades slip off the wheels on these saws is because one or both wheels are not turning true to the blade. This can be caused by:
- Missing or worn tires on the wheels. The rubber tires have to be on the wheels and they have to be in good condition.
- Occasionally the screws holding the sprocket on the driven wheel come loose and the wheel will wobble causing the blade to come off.
- Both wheels ride on bearings and shafts that, if seized, worn or broken, will let the wheel wobble enough that the blade won't stay on.
- If the blade is stretched or twisted from use it won't stay on very well.

I can't find a Bosch model GCM800 saw in their library but regardless; all arbor nuts, bolts, etc. that hold on blades will loosen if you turn them in the same direction the blade spins when cutting. This makes them self tightening so the blade won't come off while in use.

seems that ur clutch is sticking.take recoil caseing of and check by turning blade by hand,if you feel the engine turning over,then your clutch drum is sticking,be sure to remove ur spark plug cap! it will be the bearing at the rear of the clutch drum,maybe a little oil and a few turns will help it free itself.hope this helps.

Cole, The cut you are describing is challenging, but possible on a 20" scroll saw. First the blade--- you call this a hollow plank. If this is something like a hollow-core door, then the 1.5" thickness will be no problem. If you have to cut through a solid 1.5" (as you would at the edge) then you have a slow go of it unless you can find a pretty coarse pitch blade (big teeth). Second, making the turn----- assuming you are making this cut somewhere near the center of the 5' lenghth, then you won't be able to simply make a 90 degree turn after you cut the initial 5 inches. But you can make an approximately 60 degree turn, then stop the saw, leave the workpiece in place with the blade still in the cut, and reset the blade to cut sideways (so that the teeth of the blade are facing to your left or right rather than pointing toward you.) Before you make this blade turn, however, you should make the other 5 inch cut, so that you don't have to make the blade turn twice. Alternatively, if the 5 x 1.5 piece you are removing is just scrap, then you can make your two 5 inch cuts just converge to a point at the middle of the 1.5 inch line so that you can remove most of the scrap without moving the blade. Then you can reset the blade more easily with the workpiece removed from the saw. I hope you found this helpful.---- Oh, one more thing! The 1.5 inch part of the cut would be a lot easier simply by using a coping saw - they are about $15. Actually, you could do the whole cut with a coping saw. Good luck! Al K

Racing on a 2 cycle engine is usually a sign of a lean condition. It could be caused by a few different things including a bad crank seal or a torn intake manifold as some are made out of rubber. I would remove the cutter arm then pull the muffler to inspect the cylinder and piston. If they are scored it will be a costly repair.

It sure sounds like a bearing gone bad or one or 2 of the cap screws at the blade end have come lose or the cap screw closest to user end is stripped.

You've answered this yourself. The blade only needs to be nipped up enough to grip. If it slips, it will tighten. Thats why, some machines have a left hand thread, as they always rotate so as to tighten in the event of slippage.
If the blade slips under normal service, suggest you clean both blade and the flanges, and just do it up a little tighter next time.

I have a stihl ms 180 that leaks bar oil all the time