worm shaft inner bearing

[realsparty]

ok Im installing a new worm shaft...the inner bearing, which is the first thing to go on the shaft is supposed to be installed by hand and should spin and move freely on the shaft according to my installation manual....it wont go on freely by hand...should I use some abrasive paper and try to make it smaller or is there a better way...brand new worm shaft...no burrs...really tight fit...I could press it on but the book says no...any thoughts ...thanks in advance...scott

[Roscoe]

The inner ring or inner race of the two part bearing is indeed a press fit.

[webee]

I don't think it's supposed to be loose. I've always used the bearing driver that Brunswick sells.

[Steve Stafford (JBEES)]

The race (11-450200) is pressed on...the bearing (11-450100) itself will slip over the race after the race is installed. A press comes in quite handy to press the race onto the worm shaft.

[realsparty]

I guess I need to udate my gearbox manual...the old green one seems to be out of date...it does say that this inner bearing(race) needs to be free moving but it makes sense that it needs to be pressed on....just a thought though Why does it have an oil hole in it? And why does the inside have a grove in it...thanks for the help all...bowltech members come through again!!!!...scott

[jim_long]

It really isn't a press fit, it's called a loose fit. The inner races of both bearings are locked to the shaft when you tighten down the fine threaded nut that holds the plate(?) that the clutch spring pushes against. The spacer in between both bearings locks the inner races (small diameter spacer) to the shaft, the outer races are locked with the large cone shaped spacer that goes over the inner spacer.

The inner spacer has a fine grove machined on the outside of it to pump gear oil to the outside (axial thrust) bearing to keep it oiled, this the bearing that takes all the in and out movement of the worm shaft. The inner bearing is the linear thrust (up and down pressure) to keep the worm shaft in contact with the wheel. The grove is just manufactured into the inner race if needed in some applications buy the manufacturer, not really needed in this application because it is oiled by the worm wheel carrying oil up to the shaft as it rotates through the gearbox.

The inner spacer application is kind of like the jackshaft bearings that are locked to the shaft through the pressure from the pulley pushing on the spacer pushing on the inner race to the shoulder of the shaft to lock everything tight to the shaft. This is why the pulley should over shoot the end of the jackshaft by about an 1/8", so the big thick washer that holds the pulley on is shoving on the pulley to the spacer to the bearing inner race to the shoulder, locking everything to the shaft tight.

It really works quit well, as long as the inner spacer does not wear and become shorter.

In a side note, I have the same problem with front loading washing machines, where people have not replaced the spacer between the two bearings. When they tighten the drive pulley retaining bolt down (33 foot/pounds) the inner races are compressed, but the outer races are locked to the housing. This puts a bind on the bearings and they will drag so much that the motor controller electronically senses the bind and shuts down the variable voltage/frequency drive system. That's when I get a call for HELP!

And just think, I learned all this working on pinsetters. And it sure was FUN learning!