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mikem
05-29-2011, 12:50 PM
My SI SHUI, Shandong, China live center turns hard and rough. It turns so hard that the work usually just slips on the taper of the center. It has been in my collection for a while, only used once or twice--looks like new. There is a slotted head plug in the other end that I screwed out to look inside but got no clue from that. Any ideas how to make this work or am I due for a new one?

KEJR
05-29-2011, 01:05 PM
Seems like something is wrong. I was thinking of getting an import live center, but I want to get a decent quality one. Maybe I'll stick with the dead centers for now after hearing about your experience. Is there no way to take it apart?

mikem
05-29-2011, 01:13 PM
It is just one bad live center in the world, I wouldn't give up based on one that doesn't work.

I thought that maybe the plug in the opposite end covered a screw that would take it apart or where it could be tapped apart from the inside?

I thought that I would check in here to see if anyone has any ideas before I order a new one.

hornluv
05-29-2011, 01:36 PM
I know the Skoda ones I use (very good centers, BTW), have a ring by the center that has two notches in it for unscrewing it. Then inside are the tapered rollers and a bunch of grease. See if there's something similar on yours.

Ryobiguy
05-29-2011, 03:05 PM
My SI SHUI, Shandong, China live center...

I think you nailed the problem in the first sentence. :D

Carld
05-29-2011, 03:34 PM
You can probably take it apart and maybe replace the bearings but by the time you do that you will wish you had bought a Royal or Skoda or some other name brand.

Highpower
05-29-2011, 09:38 PM
I thought that maybe the plug in the opposite end covered a screw that would take it apart or where it could be tapped apart from the inside?

I recently replaced the bearings in a similar live center that was very rough. Removed the screw, inserted a round punch and applied a hammer -- popped right out. A bearing separator, arbor press and $8.00 worth of bearings and it's back in business.

lane
05-29-2011, 10:00 PM
Take the plug out of the end. Take a long pin punch through the hole and knock the center out of the bearing . take the bearings out and replace . put back together . Be good again.

mikem
05-30-2011, 07:07 PM
THANKS FOR THE TIPS!

Got most of it apart and maybe the problem is dried up grease and some junk in there. I got out a small coil of swarf like steel. The thrust bearings came out with the center but the radial deeper inside is still stuck in the bore. The punch won't catch the edge of it to push it out. The center hole bore is larger than the hole for the pin punch. I sprayed some oil in it and with the swarf out it feels 90% better.

My next idea is to take some brake cleaner and wash out the old grease and chips and put in some new grease. Is Brake cleaner OK for a solvent? I have auto grease but it seems too heavy. I have some white lithium grease that I think might be OK. It is a lot lighter viscosity. Or was the plug in the end for filling it with oil instead of grease? Maybe clean it out and put in some 30 weight oil? Thanks--MIke.

Carld
05-30-2011, 07:10 PM
The brake cleaning solvent will work and compressed air to blow it out. I would use a high temp wheel bearing grease in it.

mikem
05-30-2011, 09:17 PM
The center was hardly used but in a drawer for many years. I hope I can salvage it.

I got it apart and washed out the gunk with brake cleaner. There is a radial bearing on both ends of the stack between the center shaft and the housing and a thrust bearing in the middle.

If the whole thing isn't bathed in oil what keeps the grease from wearing away at the pressure points and going dry there?

Isn't high pressure wheel bearing grease really thick like jello?

lakeside53
05-30-2011, 10:16 PM
Like with your car wheel bearings, the grease flows around when the races get warm..

You might want to consider grinding the taper when you get it assembled.

mikem
05-31-2011, 11:33 PM
You have been really helpful! I got the bearings cleaned, lubed and pressed back into the center. It is much better--when I need it again, I'll report back how well it works! Thanks--Mike.