Verifying my Powermatic 66's center trunnion position at zero degrees tilt

[Chris Comfort]

Hi all,

First time poster here and looking for some assistance, so many thanks in advance.

I just purchased a 2003 PM 66-TA saw for what I think was a fair market price for my area (central Texas), $1,900. It's configured with the 5HP Baldor motor, extension table, rolling base, and motor cover. Seems it was lightly used the by the previous owner's uncle and, from outward appearances, is fairly pristine -- save for some surface rust on the tabletop and wings. Providing this info for other folks that might be researching prices.

To the question at hand: in the process of cleaning and prepping to replace the bearings and belts, I noticed that the center trunnion sits higher in the front trunnion than in the rear trunnion when the blade tilt is zeroed out. In the front, the center trunnion is about 3/8 in. above the top of the front trunnion; in the back, the center trunnion is flush with the top of the rear trunnion. See the photos below if you have access to them. I do know that when assessing the saw during the purchase process the blade sat 90º to the tabletop in the zero position when checked with a square, so seems like all should be good. However, since it caught my eye, I thought I'd verify with other users.

Front
front-trunnion-position.jpg

Rear
rear-trunnion-position.jpg

Do I have anything to be concerned with here?

Cheers!

Chris

[Thomas McCurnin]

I'm not a Powermatic kinda guy, but as long as the blade is 90 degrees to the table and a consistent distance from the miter gauge and fence, and when tilted can go to 45 degrees or a little beyond, I think I'm good with the saw.

[Bill Dufour]

If nothing is attached to that extended part it just goes along for the ride. I would think there is a rib or boss under the table above the more raised arc casting.
Your grammar is very confusing! you refer to three trunnions but only seem concerned with two. It only matters how the front trunnion sits in the front casting and how the rear fits into the rear and how the center sits on the center. It is entirely possible all three trunnions are different diameters. Unlikely but possible.
Bill D

[Marc Fenneuff]

FWIW, mine is higher in the front than the back

pm66 trunion.jpg

Recall that you typically shim the table to align a cabinet saw; so when you check your blade runout at 45*, if you are out then shim up the table and leave the trunnion alone.

I did not need to shim my table to get within a couple thou at 45*.

[David Kreuzberg]

Has the saw's performance been compromised by bad belts/bearings? I would think a pristine 66 would be good to go as-is. Heck, my 5HP 66 is over 28 years old and still runs like the day I installed it...on the original bearings. You could be creating a lot of work for nothing.

[Bradley Gray]

I would definitely try the saw before rebuilding.

[Bill Dufour]

Nothing wrong with replacing 20 year old grease in high speed bearings. Were they sealed or shielded?
I like Dupont chain saver lube spray for sliding stuff like those trunnions. Wax in a spray can. does not attract dust after it dries.
BilL D

[Chris Comfort]

Thanks for your thoughts, everyone -- I'm not going to concern myself with it for the time being, and see how things go once the saw is back up and running. Cheers!