Burning old grease out of bearings, "How To" or "Don't Do?"

[yoothgeye]

Cody and I were working on bikes sometime last year and I pulled a really gummed up set of bearings out of a bottom bracket. I threw them into some mystery fluid, something flammable that I thought would loosen up the grease real fast. I swished them around and pulled them out and they were still completely packed, so I put them on the shop floor and got the propane torch and put the flame right on them.

The fluid and old grease caught fire and I kept the heat on as the old grease leaked out onto the pavement. Then I picked them up with a screwdriver and tossed them back into the cleaner, which quenched them quickly.

I them removed them from that, wiped them with a shop rag and they looked like new.

Since then I have used this method many times on BB bearings and headset bearings to remove all the old grease from the bearing cages. I always just use the propane torch (used for plumbing) and never heat the bearings red hot. I always quench the heat in something oil based.

So, besides health, environmental, and safety issues (fumes, burns, etc...) would you say this is a "How To" or a "Don't Do"?

I haven't had any issues with bearings I've done this with. It works fast.

Side note of warning, when I was a kid I was playing with a torch "chasing" some fallen solder around the garage floor and dad warned me not to heat concrete in one place too long or it might "pop."

 

[detroiter60]

Next time use good old Mineral Spirits.It cuts all of the old hard crud.

 

[yoothgeye]

Next time use good old Mineral Spirits.It cuts all of the old hard crud.

Oh I will, I will soak them for about 30 seconds, then take them out and burn them. I just get in a hurry. :mrgreen:

I use paint thinner sometimes, basically whatever I can find. I like Simple Green, but I usually just take whatever I can find on hand.

 

[user 135]

I probably would not use that method. Do you think the heat affects the integrity of the bearings?

 

[CCR]

I usually just scrub them in the parts cleaner tank full of simple green and use a pipe cleaner to knock the grease build up out of the cages. Your way sounds more dangerous and fun though

 

[yoothgeye]

I don't think I'm getting them hot enough to alter their temper.

 

[beatcad]

I kinda Dought a propane torch would heat up the balls or cage all that much.

I always soak in kerosene. That's good stuff.
The fastest and best way is a can of brake cleaner.
now that stuff will clean old grease out fast.
Than scrub it w/ a toothbrush.
buy the car parts house brand, usually $1.99.
and make sure you wear rubber gloves and more important safety glasses!
you get that stuff in Yer eye and you'll be in a world of hurt!

 

[SCHWINNRAY69]

Never cleaned bearings like that, but when I was stripping the Hot Rod Deluxe, I used a propane torch on the bottom bracket to get the grease out that I couldn't get when I washed the frame :wink:

 

[Voyager Al]

Id worry about longevity of the sheetmetal cage. heat screws up sheetmetal. I just soak my parts in a kerosene/2 stroke gas mix. Sorta "what ya got layin around" solvent. 1 night, and a plastic scrub brush, gets em clean. Its bad enuf I mig weld in the garage, with the safety can at the far end of the garage. Open flame? Not me.
I was busted by Osha years ago. Fines out the kazoo. I use all approved containers,plunge cans,etc, and am as safe as I reasonably can be. But I still hate those bureaucratic .......s......

 

[beatcad]

Don't know what I was thinking when I said brake cleaner in my earlier post.
I meant carburetor cleaner.
even more important w/ Carb cleaner!!! Eye protection!!!
I put the extra exclamation points there because if you get that stuff in Yer eye you'll wish you weren'
t born!
ask me how I know :shock:

 

[slacker]

Gas and many solvents will burn at 350-500 degrees. That is definitely hot enough to alter the temper. The quick quench may alter them further.

 

[B607]

I'd say any bearing you heated is toast. Please don't sell them to any of us! It takes upwards of 1500°F to completely soften steel. (all steels are different, this is a generalization) You know you've reached the critical temp when the steel goes non-magnetic. But it only takes between 250°F and 400°F to draw back the temper. Drawing back the temper softens it somewhat from the hardened state. If you hit them with a torch, you went way over 400°F, that's for sure. Unless they are taken up to the critical temp. first, ie, 1500°F before quenching, your quenching did nothing to the steel except cool it off.

NEVER NEVER heat parts that are hardened. :!: Gary

 

[XC204]

Sounds like a recipe for " Burning Man" :lol: I've been using this stuff called Super Clean and it works! And says its biodegradable so down the drain no can of thinner to get rid of. My parts cleaner is in the garage and mineral spirits in it but this stuff I can use inside in the basement .
http://shop.advanceautoparts.com/webapp ... fragment-1

 

[DIABLO67]

I always soak mine in mineral spirits. Soaking works best for me. I usually have some new bearings around for those "has to be done today!" projects, but I still soak the old ones for future projects. After a day or two hit them with an old toothbrush and they look like new! Best thing to do is go to the store and get some Hillshire meats in the little tupperware type container, make a huge sandwich, filll the empty container with mineral spirits and soak the parts. makes sure to wear eye protection while making the sandwich!

 

[Green P1]

I kinda Dought a propane torch would heat up the balls or cage all that much.
The fastest and best way is a can of brake cleaner.
now that stuff will clean old grease out fast.
Than scrub it w/ a toothbrush.
buy the car parts house brand, usually $1.99.
and make sure you wear rubber gloves and more important safety glasses!
you get that stuff in Yer eye and you'll be in a world of hurt!

x2 on the brake cleaner. x2 also on not getting it in your eyes or any open cuts... been there done that too many times.

 

[streetpirate]

B12 Chemtool carb cleaner works good, but it's NASTY stuff to breathe

Gasoline has worked well for me too.


All solvents are bad for you to breathe and be in skin contact with. Every one of us knows that, but probably doesn't take precautions because we're only occasionally exposed to the stuff.
The trouble is, every time you are exposed to solvents you become more sensitive to them, and you can't just buy back your health later.

get some rubber chem gloves and a respirator with changeable filters. (make sure to keep the respirator in an airtight plastic bag when not in use, exposure to air wears out the filters) I like to wear those 3M high school chemistry-style safety goggles too. I didn't wear a respirator when I was painting my rrbbo7 bike, and got a scare when I was laying down the clear. My chest locked up and I had a hard time breathing for 3 days.

I might look like a dork, but I can breathe.

 

[Ratfink1962]

I dont believe you will alter the temper of the ball bearings if you are just warming them up to get the grease to soften. it is very possible to overheat the cages since they are much thinner than the ball bearings, but if you dont get it red hot, you should be ok.


But the real reason I am replying is because of the safety issue, specifically the brake cleaner comment.... Under no circumstances should a person use a torch or otherwise weld on anything that might have brake cleaner residue on it

Seriously, go read this article, it could save your life.
http://www.brewracingframes.com/id75.htm

 

[Sinner4]

That's a good way to burn down your shop or house. De-greaser, hot water and soap, or the old school method, gas in a metal can outside. Get a parts cleaner like I have, I've had it for a while now and haven't used it yet...

 

[yoothgeye]

Seriously, go read this article, it could save your life.
http://www.brewracingframes.com/id75.htm

I read that article years ago and I warn anyone I know that welds, but the issue there is not burning the brake cleaner, it was the MIG and the brake cleaner together, still though, after that article I only use the stuff to blast stuff off, never before welding. When I need to clean a part of grease or whatever before welding, I use the torch.

 

[deorman]

You might well get away with it, but if your heat input and dissipation rates are not equal, you can effect the "temper" as well as any type special surface treatment with as little as 200 Fahrenheit, though not always, and probably not much. If you hit 400, you've changed it. The center cone hot-spot of a Harry Homeowner propane can be a couple thousand degrees, That's blacksmith hot. :|