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David Spurr
10-02-2015, 7:06 PM
Heard a noise this afternoon. Sounds like a piece of wood stuck between pully and belt. Not the problem, I checked. Belt pulley on arbor is hot and so are the belts. The bearings, arbor and belts are relatively new from Powermatic, maybe 5 years. Saw has not been used very much, its a home shop. Saw is the older mid 70's model and the arbor assembly is the new one. Does the hot pulley indicate the outside bearing is going bad? Like I said, it has not been used very much since I rebuilt it. Any and all help is appreciated. Thanks, David

Charles Lent
10-02-2015, 7:23 PM
Pull the belt off and turn the saw pulley, and then the motor pulley by hand. Listen and feel for problems like bearings, etc. You may also need to remove the blade. It may be your motor bearings this time. The test should tell you where the problem is (motor or saw) and you can then narrow it down further from there. Hard to turn or gritty feel is a dead giveaway.

Charley

Matt Day
10-02-2015, 8:02 PM
Are the belts tight? Loose belts could cause friction = heat.

Anything rubbing anywhere?

First with the saw off of course, turn the blade by hand and see how smooth it is. Next remove blade and belts, turn arbor and turn motor shaft, see if anything doesn't turn smooth.

David Spurr
10-02-2015, 9:00 PM
HOLY CRAP!!!! The pulley was completely loose. Loosened the belts and the pulley almost came off with them. Tightened the set screw and all is well so far. Thanks for the help Matt and Charles.

Bob Vallaster
10-03-2015, 1:55 PM
Just a drive-by reader here, not acquainted with this saw in detail. Most pulley-to-shaft designs incorporate keyways in shaft and pulley and a key under the set-screw. If yours was designed for a key, is it in place? Could be square stock or a half-moon ((woodruff) piece. A key can be forgotten or can move laterally if the screw backs off. If missing, a set-screw will gleefully chew a ragged scar in your shaft/arbor. Worth a check before your next cut.

BobV

Charles Lent
10-03-2015, 6:22 PM
Glad I was able to help, but I agree with BobV. Check the pulley for a key to make certain that it's there and doing it's job. An old machinist trick for keeping set screws from loosening is to put two short set screws in the same hole. One set screw to lock the key and pulley in place and the second set screw to lock the first set screw in place. Of course you could do the same thing the modern way and use Blue Locktite on just the one set screw. Just make certain to use the Blue Locktite and NOT the red or orange. They will guarantee that it never comes off, even when you want it to. The blue will let you take it apart with normal tools, if you should ever need to.

Charley