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Dave S.
11-04-2011, 06:43 PM
The problem. Have a two cylinder air compressor that has eaten the rear bearing. Needel bearing in a blind hole at the back of the crank case. No way to get any kind of puller in.
The solution. Heat some grease you have on hand and fill bearing with grease. Take a brass rod and hit with BFH. Grease just gets expelled between bar and old bearing shell. Machine rod to tight fit to shell. Don't want to stink up the shop more heating grease again. Fill with heavist oil I have hit with BFH again. Oil squrts out between rod and bearing shell.
Takd break have dinner ponder what do I have that will deform when I hit it with the BFH but is thick enought not to just squrt out.
Light bulb comes on. I have modeling clay that I have been using when making molds for lost wax patterns.

Heat up a lump of clay in my hands till soft, form a plug and set it in the hole. Place brass bar in place and hit with BFH hit again, and again. Take a look and it is moving the bearing shell up out of the hole. Add some more clay and keep hitting. Shell come out of hole. YES:D

Here are some photos after the fact.

Dave

http://i132.photobucket.com/albums/q3/Dave_Sohlstrom/100_1090.jpg

http://i132.photobucket.com/albums/q3/Dave_Sohlstrom/100_1092.jpg

http://i132.photobucket.com/albums/q3/Dave_Sohlstrom/100_1093.jpg

DFMiller
11-04-2011, 07:07 PM
Great solution to th problem. Did you get all the clay out after?
Thanks for sharing this idea.
Dave

boslab
11-04-2011, 07:25 PM
well done, a cunning plan sir, so cunning you could put a tail on it and call it a weasel
mark

becksmachine
11-04-2011, 07:26 PM
To quote our friends from down under, "Good on you mate"!

:D

Dave

Dave S.
11-04-2011, 07:33 PM
Thanks guys

Yes because there was oil and grease remains in to hole the clay could not stick to anything. I took a piece of flat stock and shoved it down into the remaining clay, gave it a twist and out it came.
The whole repair of the compressor was pending on getting the old bearing out of the hole. Now I can proceed.

Dave

chipmaker4130
11-04-2011, 08:56 PM
Just curious Dave, but why did you heat the grease? I've always used the stiffest stuff I could find and did the job cold.

Gordon

Dave S.
11-04-2011, 09:49 PM
Gordon

My thought was that if I heat the grease then I can pour it into the hole and have a minumum of air. The grease I had on hand was way to thin.

Dave

RoyClemens
11-04-2011, 11:01 PM
Good idea. Never had much luck with the grease trick myself. Surprised that anyone here would admit to owning much less using a BFH though.

firbikrhd1
11-04-2011, 11:23 PM
Clay was a great idea! I'll have to put that in my memory banks in case I ever need it. Using grease works well when removing pilot bearings when you change a clutch. That's one I have done. But clay? Good thinking.

x39
11-04-2011, 11:31 PM
If one can get at it, just run a couple of beads of weld inside the old bearing outer race and it will shrink enough to be easily removed.

JoeLee
11-05-2011, 12:17 AM
That was good thinking to hydraulically remove the bearing. I had the same problem on my old Campbell Hausfeld compressor. Torrington bearings in a blind hole can be tricky to remove especially after you chip away the rim. I made a T bolt that just fit inside the bearing and tigged a blob on each end and slide hammered it out. The only problem with your method is you have to be careful you don't poke a hole through the casting when your pounding the rod.

JL....................

J. Randall
11-05-2011, 12:29 AM
In a pinch creamy peanut butter works about as well as the clay does.
James

Fasttrack
11-05-2011, 12:34 AM
If one can get at it, just run a couple of beads of weld inside the old bearing outer race and it will shrink enough to be easily removed.

I've not heard that one before. Thanks for sharing!


I use cold grease all the time. In fact, every time I load the grease gun again, I keep the old spent tubes. There's usually a dab of grease left over. I wipe it out with my finger and glob it in a tin cup. This is the grease I use to remove bearings. Yes, I am a cheap, tight-fisted b*stard. :D

boslab
11-05-2011, 05:19 AM
out of curiosity i put a pressure guage on a greasegun, i got 9000psi!
mark

x39
11-05-2011, 07:09 AM
I've not heard that one before. Thanks for sharing!
My pleasure! Works good, I learned it from an old farmer down the road from me.

bandmiller2
11-05-2011, 08:15 AM
Thats an especially good trick to know if your replacing the needle bearings in the endplate of hydraulic pumps and motors.Support the back of the cavity and use disgression when hitting the punch as it is entirely possible to punch out the back of the casting. Frank C.

Black Forest
11-05-2011, 08:21 AM
Support the back of the cavity and use disgression when hitting the punch as it is entirely possible to punch out the back of the casting. Frank C.


And just where can one purchase this disgression when one needs some?

Lu47Dan
11-05-2011, 09:03 AM
Bob good trick with the modeling clay. I have used wheel bearing grease to push out pilot bearings and such.
I think the word Bandmiller was thinking of was "Discretion"


dis·cre·tion [dih-skresh-uhn] noun
1.
the power or right to decide or act according to one's own judgment; freedom of judgment or choice: It is entirely within my discretion whether I will go or stay.
2.
the quality of being discreet, especially with reference to one's own actions or speech; prudence or decorum: Throwing all discretion to the winds, he blurted out the truth.
Dan.

aboard_epsilon
11-05-2011, 09:16 AM
i remember when i went to a lot of trouble..all for nothing, to get a blind bearing out of a gearbox

this one here ..in the middle of the picture

http://img.photobucket.com/albums/v190/aboard_epsilon/rover%20420/cleancasing.jpg

i went to the trouble of making this slide hammer device .

http://img.photobucket.com/albums/v190/aboard_epsilon/rover%20420/mystery.jpg

http://img.photobucket.com/albums/v190/aboard_epsilon/rover%20420/cams.jpg

next post ...is what i should have done ...

was told this after i had gone to the trouble .

aboard_epsilon
11-05-2011, 09:20 AM
Turns out, all i had to do was to turn the casting over ...and pour boiling hot water out of a kettle on the area marked in red ...and the bearing will just fall out ...which it did do

http://img.photobucket.com/albums/v190/aboard_epsilon/rover%20420/hotwaterhere.jpg


This info is worth remembering before you struggle ...when there is a simpler solution .

all the best.markj

Dave S.
11-05-2011, 11:29 AM
Good idea. Never had much luck with the grease trick myself. Surprised that anyone here would admit to owning much less using a BFH though.

BFH only used in extream cases. Hammers and machinery do not mix well.

aboard_epsilon

The boiling water idea is a great one. Will have to try and remember it. Does it work on cast iron?

Dave

Fasttrack
11-05-2011, 04:23 PM
Does it work on cast iron?



Although I've never tried it, I'm going to say, "No!". Cast iron is very dimensionally stable. It's linear coefficient of thermal expansion is roughly half that of cast aluminum. Therefore, it would take roughly twice as great a temperature change to yield the same effects as would be seen in cast aluminum.