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View Full Version : Belts/bearings on Powermatic 66 table saw circa 93-94



Scott Davis
12-27-2014, 5:49 PM
Hi all, I hope everyone had a great holiday. I have an old PM 66 and it probably needs a tune up. One the things that I notice it that the blade has a "memory" and if you turn it around 90 degrees forward or backwards it will roll back to where you started. This saw sat for about 10 years when my Dad stopped using it regularly. I am not sure if the belts have a memory now. I have taken the table off this saw when I got it but never investigated the belts and pulleys. It was a pretty big chore just taking off the table top. It is a gold machine so I believe it is circa 93-94.

1) how can I tell if I need new belts?
2) should the blade do what I describe or is that wrong?
3) how do I know if I need new bearings?
4). I don't have machining tools or knowledge of bearings at all, can anyone describe how to replace bearings in a PM 66? Are tools required other than typical woodworking shop stuff so I can prepare.

thanks for any input, I am worried about this being a Pandora's box but might as well learn I guess! Taking this beast apart by yourself is not trivial. If anyone can walk me through this investigation I would be appreciative. I did look for old threads but nothing was specific to this that I could find

Scott

David Hendricks
12-27-2014, 7:20 PM
Hi all, I hope everyone had a great holiday. I have an old PM 66 and it probably needs a tune up. One the things that I notice it that the blade has a "memory" and if you turn it around 90 degrees forward or backwards it will roll back to where you started. This saw sat for about 10 years when my Dad stopped using it regularly. I am not sure if the belts have a memory now. I have taken the table off this saw when I got it but never investigated the belts and pulleys. It was a pretty big chore just taking off the table top. It is a gold machine so I believe it is circa 93-94.

1) how can I tell if I need new belts?
2) should the blade do what I describe or is that wrong?
3) how do I know if I need new bearings?
4). I don't have machining tools or knowledge of bearings at all, can anyone describe how to replace bearings in a PM 66? Are tools required other than typical woodworking shop stuff so I can prepare.

thanks for any input, I am worried about this being a Pandora's box but might as well learn I guess! Taking this beast apart by yourself is not trivial. If anyone can walk me through this investigation I would be appreciative. I did look for old threads but nothing was specific to this that I could find

Scott

To get to the bearings you need to remove the pulley first, once that is off you can then loose the set screws, then use dead blow hammer and block of wood and knock it out of there. You will need to get the bearings off the shaft, i advise going to harbor freight and get a bearing splitter set. There are two bearings sandwiched around spacers. I used the spillter and a impact drill to get the bearings off all at one time. Just make sure you support the inner race. This is a broad over view, there are several other things you can do such as freezing the bearings and shaft and then trying to pull off.

CPeter James
12-27-2014, 7:41 PM
Is it a 2 belt set up or three. This is about the time that they changed. I have a 2 belt saw and found that the only place to bet belts was PM. They were THAT expensive. The bearings are very inexpensive.The arbor assembly comes out as one piece. The belts are probably dried and that is why they take a "set". Do replace them. Do use AX series belts. Those are the cogged ones. When you put the arbor assembly back, make sure to get it in the correct location right/left so that the blade stays where it is supposed to when you tilt it. You will use the bearing puller/splitter enough to quickly justify is small cost, This is my recommendation:Pittsburgh Automotive - item#93980. It is $45. I have one and it has served me well.

CPeter

CPeter

Lee Schierer
12-27-2014, 7:49 PM
there are several other things you can do such as freezing the bearings and shaft and then trying to pull off.

Won't freezing the bearings make them smaller and harder to get off?

Carroll Courtney
12-27-2014, 8:10 PM
Well if there is no problem then don't change them.94 is not that old for a PM 66 even if your Dad use it daily.After market bearings are not that expensive but exact replacement will cost you some bills.I've price them when I took mine apart down to the last bolt/nut so I went with the after market.
If your going to take yours apart then by all means replace the bearings,but for just a tune-up?Na,I wouldn't.Belts? mine does the same thing,its the belts that has the memory.I think that even link belts would do the same thing.But since you have the top off,then go ahead and replace the belts,even if they look decent.Square the table to the blade,check to make sure the blade is at 90*/45* adjust your stops if needed.Just my thoughts----Carroll

David Hendricks
12-27-2014, 8:12 PM
That's a suggestion I have read before, but I agree I would think so. But the shaft will get smaller as well, because it is denser than the bearings maybe it stays smaller longer. I did it with the bearing splitter supporting the under race and the impact hammer, I was able to take them all off at the same time with no damage to the bearings. I do recommend freezing the shaft when you put them back on for sure. You can also use a candelabra type bulb to heat the bearings before trying to put them back on.

John McClanahan
12-27-2014, 11:05 PM
As a PM66 owner, I say to hold off on new bearings unless you are sure it needs them (I doubt it does). The belts have developed a memory, but that alone doesn't mean they are bad. If the belts don't have cracks or areas of separation I would just loosen the belts and slip one of them a bit so the areas where they contacted the pulley while the saw was unused is offset (the "flat" spots don't match up). That should reduce the memory effect a bit. Using the saw will help, too. If you do need new belts, check ebay.

John

Scott Davis
12-28-2014, 9:28 AM
Thanks for all the replies. I haven't pulled the table off yet but was thinking about it. Currently the rails and extension table are still on it so it would be a chore to do it. I am not currently at home so can't remember if it has two belts or three. I will have to look in a few days when I get home.

can the belts be accessed without removing the top? If so I guess I could spin the bearings and feel how they turn to decide? Not sure what you would feel with the arbor still in place or whether top has to be removed just to inspect it?
there is also some vibration but I have only ever used this saw so have nothing to comare. I could run it without the belts to see how different it sounds as a way to think about the bearings too I guess.

i have never used a bearing splitter/puller and would hate to cause a problems I don't already have. Looking at the picture of that tool though it looks pretty self explanatory

how you you get the bearings back on the arbor? Does the splitter do that too? And by "support the inner race" do your wan to aply the pressure to the inner race the outer race of the bearing?

David Kumm
12-28-2014, 10:41 AM
Set the new bearings on a light bulb and heat the inner race. The bearings will slip on but go fast as they cool as soon as they touch the shaft. I use optibelts as they don't need to be matched. Keep in mind that the motor has two bearings also. If the arbor bearings are changed, I'd also change the motor bearings. They run hot so they tend to fail before the arbor bearings. C3 for the motor bearings like SKF JEM and SKF Explorer normal clearance for the arbor unless PM has a special size. Explorer are a little better precision ABEC3 and not that much more expensive. Dave

Don Jarvie
12-28-2014, 11:03 AM
As others have said most likely the bearings are fine. You need to take the top off to access the belts. There will be 2 or 3 bolts that need to be loosened and the motor will swing and relieve the tension on the belts. Once the belts are removed spin the arbor and if it spins freely and doesn't make a bad grinding sound leave them.

Definitely replace the belts. Take them to the auto parts store and get matching belts. Matching means they were cut from the same roll.

Once the belts are replaced get a copy of the manual and set the saw up according to the manual.

CPeter James
12-28-2014, 12:11 PM
I don't think you will find those belts at an auto parts store. They are very short and when I replaced mine, not even McMaster Carr had them. I had to get them from PM direct. Be sure to use the AX series belts.

CPeter

Scott Davis
12-28-2014, 2:26 PM
Very good. Sounds like I have a plan of attack. Will get the belts to start and examine the bearings to decide from there. Would rather not mess with bearings unless I really need to
Thanks all

Ray Newman
12-28-2014, 2:43 PM
Before buying new belts, lower the blade completely (or remove it) and run the saw for about 15-20 minutes under no load. My Uni-saw belts are about 25 years old and sometimes take a set, but running the saw for a while gets things back to normal.

Lee Schierer
12-28-2014, 2:49 PM
I don't think you will find those belts at an auto parts store. They are very short and when I replaced mine, not even McMaster Carr had them. I had to get them from PM direct. Be sure to use the AX series belts.

CPeter

Automotive belts do not have the same cross section as power drive belts. Most cities have an industrial supply house that can get you the proper belts.

Don Jarvie
12-28-2014, 4:25 PM
I've always use auto belts and have never had an issue. A belt on a car is pulling as much torque as a saw or planer.

CPeter James
12-28-2014, 5:34 PM
It isn't the strength, it is the profile. Automotive belts have different profile dimensions than fractional horsepower belts and may bottom out in the pulleys. If you can get the same series belt at you local auto parts place, go for it. Just be sure that you are replacing apples with apples and not oranges.

CPeter

Brian Henderson
12-28-2014, 7:38 PM
I've always use auto belts and have never had an issue. A belt on a car is pulling as much torque as a saw or planer.

Maybe I was just unlucky but the last time I went into an auto parts place for something other than auto parts, the guys behind the counter were totally useless. I needed a fuse for an inflatable Halloween decoration, I asked the guy at the counter about their fuses and he had no clue. If you can't tell him what kind of car you have so he can look it up in their computer, he had no idea of any of the technical specifications of what they sell. I can just imagine this guy asking what auto manufacturer makes the Powermatic 66.

Ed Edwards
12-29-2014, 2:53 AM
here's what I found on line about belts
Also, as mentioned about try to get a "matched set". If not matched, try to at least get belts with the same numbers or lot numbers. The last thing you want is to have 1 belt tight a the loose
​EdClassic Cogged AX,BX,CX V-Beltshttp://www.vbelts4less.com/assets/images/classicseriescogged.jpgClassic Cogged AX, BX, CX Section V Belts
• Special top layer with fabric
• Tough tensile member for greater strength
• Molded Cogs
• Improved heat dissipation
• Greater flexibility for smaller diameter pulleys
• Transmits higher horsepower
• Antistatic, oil and heat resistant
SUB-CATEGORIES



http://www.vbelts4less.com/assets/images/axa.jpgClassic Cogged AX V-Belts (http://www.vbelts4less.com/Classic-Cogged-AX-V-Belts_c_29.html)1/2" Width



http://www.vbelts4less.com/assets/images/bx.jpgClassic Cogged BX V-Belts (http://www.vbelts4less.com/Classic-Cogged-BX-V-Belts_c_30.html)21/32" Width





http://www.vbelts4less.com/assets/images/cx.jpg (http://www.vbelts4less.com/Classic-Cogged-CX-V-Belts_c_31.html)