How to remove old wheel bearing grease?

[hiker]

it's time to repack the wheel bearings...

I've read three methods for cleaning the bearings before repacking them with fresh grease:

1. just wipe away the old grease with paper towel

2. use brake cleaner

3. use brake cleaner then wash with soap and water.

My question is -- what method do you use?

[Inland RV Center, In]

Originally Posted by hiker

it's time to repack the wheel bearings...

I've read three methods for cleaning the bearings before repacking them with fresh grease:

1. just wipe away the old grease with paper towel

2. use brake cleaner

3. use brake cleaner then wash with soap and water.

My question is -- what method do you use?

You must usea grease solvent.

Gasoline works grgeat.

Andy

[markdoane]

Mineral spirits works good. Or use any commercial parts cleaner solution followed by an alcohol rinse then air dry.

[airgead-cana]

Rinse the parts in cheap gasoline in a plastic coffee container (one for each wheel so as to not mix up the components) outside for ventilation.

Um... I don't think the enviromental or dermatologist people would approve so we'll call that a joke.

but it would work...

[wmarsha]

it is a highly effective solvent, but it is very dangerous, even the crappy fuel we get today. if you do not have a solvent tank, buy some cans of brake clean and use that-wipe the majority of the grease off first with the paper towels, then use the brake clean. do not spin the bearings when dry, regrease using the old palm of the hand trick or a bearing packer.
be safe, first
bill

[hiker]

thanks for the fast response... so far everyone uses a solvent to clean away the old grease, with one poster recommending an alcohol rinse.

Has anyone had good results just wiping away the old grease? If not, why?

[RLS]

You are trying to clean ALL the old grease off. This would include the old grease in between the bearings. Just wiping them does not really clean them. You need some type of solvent to do it right.

[markdoane]

Why don't you wipe off as much as you can. Then clean them with solvent and see how much old grease and crud you missed?

[centennialman]

I use the brake solvent and a soft bristle brush. Then, blow out with an air compressor. Repack by hand.

[hiker]

Originally Posted by RLS

You are trying to clean ALL the old grease off. This would include the old grease in between the bearings. Just wiping them does not really clean them. You need some type of solvent to do it right.

The expert mechanic in a how-to video I watched just rolled the bearings on paper towel which removed most of the grease between the bearings. I understand that this technique cannot remove all the old grease, but it seems to remove most of it. Not unlike draining old oil during an oil change removes most but not all of the old oil.

Does even very small amounts of old wheel bearing grease contaminate the new grease?

[AirsDream]

Wiping / rolling can't nearly get it all. And what is left may well have the most dirt/ abrasive in it. It also leaves grease thay may or may not be incompatible with the grease you're about to use to re-grease. Solvent is the only way to get it all out. Gasoline very dangerous due to flammability and toxicity concerns; mineral spirits / kerosene somewhat less so, but take longer to dry.

Experts recommend never using compressed air to blow / dry the solvent out of bearings, as this could cause spin at high speed and galling, etc. I do it anyway, making REAL sure to have rag / paper towel pressure on all parts so nothing can move. Then a littlefinal air dry in the sun while I take a break before repackng.

[r carl]

Wash with solvent or gas and blow the bearing out to clean and dry it, you may have to wash again and dry if grease comes out when you blow out with air. One of the reasons to blowing it out is the air will blow out the dirt inside the bearing. Do not mix up the bearings, they go back in their original position, keep them with the hub they come out of. You can get away with just wiping the inside of the hub clean though. Dont buy a cheap grease when you repack your bearings, it could cost you dearly.

[loudruff]

When repacking the bearings, DO NOT dip them into your grease tub.. Use the old palm of the hand method so you don't contaminate the whole tub of grease.

[richinny]

one other part of repacking the bearings is to inspect the bearing rollers and race. if you leave old grease, you can't inspect the bearing properly.

[Kevin245]

Originally Posted by richinny

one other part of repacking the bearings is to inspect the bearing rollers and race. if you leave old grease, you can't inspect the bearing properly.

Absolutely. A critical part of the re-packing process is a thorough visual inspection. Here's what we found last Fall.

http://www.airforums.com/forums/f437...eck-57131.html

[NevadaGeo]

Ok, next: Who's grease do you prefer to use to repack the bearings with?

[Wayne&Sam]

Originally Posted by AirsDream

Experts recommend never using compressed air to blow / dry the solvent out of bearings, as this could cause spin at high speed and galling, etc.

I can't believe that spinning dry bearings with air or by hand for a few seconds under no load would cause any harm.

Isn't it kind of hard to resist?

[AirsDream]

I don't think spinning them by hand under no load can cause any harm - anyway, I can't resist. But I don't air-spin 'em.

They are ground to very tight tolerances and are precision hardened; just a little nick can start bad things to happen. I've had bearings fail, once on a rented trailer far from the nearest paved road, and now I take no chances with them. They are one of the few "show stoppers" in RVing, and I don't want my show stopped!

[r carl]

Originally Posted by NevadaGeo

Ok, next: Who's grease do you prefer to use to repack the bearings with?

Now that question can lead to looong arguments! But if you want to use the absolute best lubricants that beats them all without a doubt use this stuff. Lubrication Engineers - LE History
Ive used their products for over 20yrs and it still impresses me. Not having to buy a single ball joint, tie rod, bearing, transmission, or motor has saved me sooo much money over the yrs. You can buy it by calling the company.

[r carl]

Originally Posted by Wayne&Sam

I can't believe that spinning dry bearings with air or by hand for a few seconds under no load would cause any harm.

Isn't it kind of hard to resist?

You can spin them with air but just not at a high speed!!! Only slowly.