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JFairman JFairman is offline
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Join Date: Jul 2006
Location: S. Florida
Posts: 7,274
There's some good 3K information in this link: Design and Function of a Turbocharger - Bearing system | - BorgWarner Turbo Systems

You should feel some lateral or sideways play of the turbo shaft because the 2 sleeve bearings on the shaft are full floating in oil.
They have oil clearance on the inside and outside and they rotate at about half shaft speed in oil inside the bearing housing never allowing metal to metal contact.
There should be no noticeable axial play with your fingers. If there is the thrust bearing is probably worn.

Also you should have some way to check for wear in the piston ring grooves or lands on the shaft. If they are worn or eroded and full of coked carbonized oil the turbo is going to still leak and burn oil at times after you reassemble it.
The piston ring oil seals are compressed and clamped in place by the bearing housing when the shaft is installed in it and they do not rotate.

Marking an inducer and exducer blade with a sharpee pen or magic marker in relation to the shaft works to realign them in balance when reinstalling the same parts on the same shaft but the nut that holds the compressor wheel on the shaft usually has a side or two ground away when it's magnetized and balanced in a VSR balancing machine so when it's all back together and torqued down that nut would have to be in the exact same position on the shaft threads or the high speed balance will be off.

Where did you get the rebuild kit? ..and what color locking paint is on the compressor wheel nut?

I'm not a turbo expert either but I've had alot of very expensive repetitive experiences with one and I wouldn't try to rebuild one if I expected it to last. I don't have the equipment to do it right and I've never done it before.
Old 01-08-2010, 09:13 PM
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