Need to remove this bearing?

[jproaster]

Hey all.
I don't know for sure why this bearing will not receive grease; the gun works great.

Took off zerk (zert?) fitting to clean; also removed grease from cavity immediately after the zerk. Upon replacing cleaned zerk, enough grease to fill the cavity will easily flow from gun...then grease squirts around the outside of fitting.

A few weeks back I had the machine heated and some grease flowed through- but I had to hold the gun tight (real tight) on the fitting.


So, I'm thinking it's time to pull the bearing. Never done that before.

So the first thing to ask is "do I need to remove this bearing and clean it?" Been using this machine for several years; never done anything to this bearing but put high temp grease in it.

Second, if I need to remove bearing, please recommend a good tool which can be used on motorcycle related issues.

Thanks for sharing.

John

Coffee roasting machine- gets up about 475F when in use.
The bearing is held in by 4 studs; stainless plate is threaded- no nuts on the inside.

 

[Phantomd]

A picture will be just about necessary to suggest a removal method for the bearing.
-If you had to push the gun onto the zerk fitting then the fitting or the zerk gun connector is bad. You should be able to build a significant amount of pressure on the lever of the gun before it leaks past the fitting.

 

[MFolks]

Should be able to remove the four bolts,with the bearing installed,most bearing places may be able to help,I built machines with shafts spinning on similar bearings,in California.

 

[Doug Arthurs]

The shaft should be a slip fit into the sleeve of the bearing and held with a set screw. The bearing is called a flange type pillow block.

 

[Phantomd]

Doug is right. Called an insert bearing. I can just see the two notches in the edge of the red housing that the bearing is designed to come out through.

Overtightining the set screws can result in early failure, my experience is if it's a low rpm and low load situation you are fine as long as you dont tighten them super hard. Good and snug is usually fine.

There should be a number written on the bearing that should help source a new one. at very least you need a shaft diameter.

 

[Phantomd]

That's a stainless bearing too, be aware of that when you order new ones. They are significantly more expensive but probably necessary in your application.

 

[LXCam]

Are you positive the zerk fitting isn't the issue. I've had several new ones that won't flow grease. Can't say I've ever seen one that worked previously have that problem though.

 

[rlitman]

My guess is that the heat is the problem. Most greases aren't made to run that hot, and at those temperatures, the oil evaporates off, leaving only the soap base behind (turning the grease into a waxy solid).

Where does the excess grease go? I'm assuming it doesn't contact the beans.

Have a look at this (they run cooler, but faster):
https://www.machinerylubrication.com/Read/239/specialty-grease

 

[jproaster]

Hey guys. Thanks for sharing.

Just for clarification- do these types of bearings get clogged (or some other issue) that prevents new grease insertion?

 

[Bondo]

Hey guys. Thanks for sharing.

Just for clarification- do these types of bearings get clogged (or some other issue) that prevents new grease insertion?

Ayuh,.... It's explained in the post above yers,.....

Dried out grease,.....

Pull it, 'n either clean it out, or replace it,....

 

[matt_i]

So here's an idea. The zerks are usually based on a 1/8 NPT thread. If you can come up with a flex hose with two male NPT ends you can screw the flex hose into the housing of the pillow block and then wind the grease gun's housing onto the other thread, tighten them both up.

Now there's no leakage short of a burst, you can probably pour 5ksi grease to it (!!)

 

[jproaster]

My guess is that the heat is the problem. Most greases aren't made to run that hot, and at those temperatures, the oil evaporates off, leaving only the soap base behind (turning the grease into a waxy solid).

Where does the excess grease go? I'm assumig it doesn't contact the beans.

Have a look at this (they run cooler, but faster):
https://www.machinerylubrication.com/Read/239/specialty-gre

I use a high temp grease that easily withstands my highest temp use.
The excess grease oozes through the front of bearing...though a little will leak behind the bearing. This is still outside the roasting chamber.

My question about possible causes of this trouble is due to the need to prepare lots of product before teardown if I need to order parts...not just clean and replace.

I've been roasting with this machine for 14 years; it's never had even a hiccup concerning grease in this bearing til a couple months back.

Thanks
John

 

[rlitman]

If it lasted 14 years, then replace the bearing and keep doing whatever you’re doing.

Even if the heat kills the grease, refreshing the grease regularly extends its life quite a bit, as you have seen. Most likely a PFPE grease would have handled the same service without regressing at all, but it’s not like regular greasing is difficult in this case.

 

[WittHay]

Hey guys. Thanks for sharing.

Just for clarification- do these types of bearings get clogged (or some other issue) that prevents new grease insertion?

Very common for pillow block bearings to get plugged. The insert bearing has just 1 very small hole for the grease to go through. The bearing has to have a tight fit to the block to seal the grease or it just comes out the front or back between the bearing and block

We use RHP bearings the most for pillow block applications. Seem to last longer than other brands. All those pulleys in the picture have 4 hole pillow block bearings behind them. Used lots in machinery.

To remove them gear pullers and cutting torches. In your case 2 prybars on either side might do it or a bar type gear puller

 

[thecj3man]

I had a fitting on a tractor axle pivot that would not take grease. I removed it multiple times and cleaned it out. I bought a lube locker grease gun coupler one day on a whim and it solved all my greasing issues. I thought it was a gimmick before I bought it, but I have been pleased with it.

 

[rlitman]

Oh, the Lock-n-lube is no gimmick! That's the best thing that ever happened to grease.