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[rockherder]

Ugh!

Having a horrible time trying to replace a Sealmaster NP-20 bearing on the arbor shaft of this saw.
This saw has two Sealmaster NP-20 bearings on the arbor shaft outside the case.
The bearing closest to the tank was making horrible grinding noises.
I cannot for the life of me figure out how to get the arbor out to change the bearing.
I'm beginning to think that the arbor must consist of two pieces and I need to take them apart???
Does anyone have any experience with the older saw?   

[GoodEarth]

I've done three this month... pretty easy actually. You have to take the cover off the arbor. Three screws on the bade side, and two on the pulley side. Two from the top down. Be careful of tearing the felt gaskets. Then, two bolts in each bearing holding it to the table, and you have to back off the four adjustment bolts. Pulley off and blade off it should lift right out of the saw case. Then Allen screws 2 each retaining the bearing, and press the shaft out of the bearing. Clean the shafts with some emery cloth and grease it and the new bearing should slide right on.

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[Steve Ramsdell]

GoodEarth is right on.  I haven't had to do this in 20 years.  But he is right that everything is logical.  Just make sure to stop and remember all the steps.  I used to work on some 18 in. HP saws for our park district.  They were used every day.

[GoodEarth]

There is a great YouTube video from HP about aligning the blade. Worth the watch if you haven't done it before.

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[rockherder]

Those are some great videos.
Thanks for pointing those out, I wasn't aware of them.

The saw alignment video is https://www.youtube.com/watch?v=viORS9UPs0k

They also have a video to adjust the carriage that I found very useful https://www.youtube.com/watch?v=cR1v6MvJTnc

I'm still working on replacing the bearings.
The outside bearing came off very easy with a pulley puller.
Then I had a great deal of trouble trying to remove the v belt pulley.
I started by attempting to use the pulley puller.
I moved it about 3/4 inch and then realized that due to the saw construction the pulley was to big to pull directly off the arbor.
The arbor cannot be tilted up as there is an internal bar in the saw that prevents it and the bearing mounts are not spaced far enough apart to allow the pulley to be removed.
Eventually, I realized the v belt pulley uses a tapered lock mechanism.
The pulley has two bolts on the side of the pulley, and two other empty bolt holes.
The bolts must be removed (from the side of the pulley) and inserted into the two empty bolt holes and then tightening the bolts will "split" the compression hub from the pulley.
I haven't tried this yet but will probably attempt it today or tomorrow.