How do I check bellhousing runout ?

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Mar 5, 2005 | 07:32 PM
  #1  
Getting ready to install the TKO600 and I want to check the bellhousing runout. How do I do this with the motor in the car. The bellhousing is off I guess I take the clutch off and.....never done it before so I need help

Another thing is the release bearing was out of whack or somethng. I had a vibration when I depressed the clutch. Nothing bad but I could feel it through the clutch pedal. Well I inspected the bearing and the middle part of it was offcenter. It still spun fine with no play, like there was nothing wrong with it except it was offcenter really wierd

Heres a pic of the bearing you can see the center part is not in the center of the bearing but off to ione side.



Here's the old one and the new one and you can see the new one is centered corectly.

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Mar 5, 2005 | 07:45 PM
  #2  
I remember trying to do that on the Lakewood I almost put in. To me, it was a major PIA. The thought still makes my brain hurt.

I gave up, put in a stock 11" "621" bellhousing and called it quits. I wasted too much time on that and measuring and re-measuringing my bearing clearances.
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Mar 5, 2005 | 08:53 PM
  #3  
Quote: I remember trying to do that on the Lakewood I almost put in. To me, it was a major PIA. The thought still makes my brain hurt.

I gave up, put in a stock 11" "621" bellhousing and called it quits. I wasted too much time on that and measuring and re-measuringing my bearing clearances.
Checking runout is easy. The clutch must be off the car and just have the flywheel on the motor, pull the plugs also to make turning over the motor easy.
Install the bellhousing then use a dial indicator with a magnetic base.
Put the magnetic base on the flywheel by reaching through the transmission hole in the bellhousing and using a number of extensions mount the dial indicator in the hole in the bellhousing.
Nothing needs to be centered just have the indicator in the hole riding on the edge of the trainsmission hole and mounted to the flywheel.
Have a friend slowly rotate the motor.
With the dial indicator zeroed in say 12 oclock take readings are 3, 6, 9 and 12.
Maximum reading can be .010 and this represents .005 runout from center. So if you start with 0 at 12 and at 6 you get .010 divide by 2 and the runout is .005. Check also at 3 and 9. No reading should exceed the .010 if the dial indicator was set to zero at one of the spots.
This is really simple, it is important and if the reading exceeds .010 make it right with offset dowels put in the engine block.
If you need more help on this post again.
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Mar 5, 2005 | 09:34 PM
  #4  
Thanks for the help, so I guess you don't need to center it as long as it is in the hole the needle on the gauge will just ride around the edge ?
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