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Anyway you can definitively tell if its either a TOB or in put shaft on M21? Just got the car running an a strange noise appears when I have the clutch out in neutral and no noise when I engage the clutch. Of course new TOB not new Transmission

Thanks for any help.
 

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Anyway you can definitively tell if its either a TOB or in put shaft on M21? Just got the car running an a strange noise appears when I have the clutch out in neutral and no noise when I engage the clutch. Of course new TOB not new Transmission

Thanks for any help.
99% of the time that’ll be a throw out bearing..
 

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Sounds like it's a rough input shaft bearing in the trans. With a properly adjusted clutch (free travel at top of pedal) the TOB is not turning when the pedal is released since it backs away from the spinning pressure plate. A rough TOB will make noise when you push in the clutch.
With the clutch out in neutral the input shaft and cluster gear are spinning in the trans. A rough input shaft ball bearing would make noise at that time and stop when you push in the clutch since the shaft then stops spinning. There are also rows of roller bearings that the cluster rides on but they seldom cause problems.
 

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Sounds like it's a rough input shaft bearing in the trans. With a properly adjusted clutch (free travel at top of pedal) the TOB is not turning when the pedal is released since it backs away from the spinning pressure plate. A rough TOB will make noise when you push in the clutch.
With the clutch out in neutral the input shaft and cluster gear are spinning in the trans. A rough input shaft ball bearing would make noise at that time and stop when you push in the clutch since the shaft then stops spinning. There are also rows of roller bearings that the cluster rides on but they seldom cause problems.
This is what I was thinking. With the right freeplay, the throwout bearing isn't touching with the clutch pedal out. But the input shaft IS turning.
 

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Anyway you can definitively tell if its either a TOB or in put shaft on M21? Just got the car running an a strange noise appears when I have the clutch out in neutral and no noise when I engage the clutch. Of course new TOB not new Transmission

Thanks for any help.
Please explain what you mean by clutch out and clutch engaged?

You have a new T/O bearing installed?. I think that is what you said.

I assume car is not moving when you are in N ?

If you replaced the T/O bearing did you replace the Pilot bushing?

IS freeplay set IAW manual?

I think you are saying the noise goes away when you engage the clutch, take foot off of pedal?

And it is present when you push the pedal to the floor?


Try this:

with car stopped, engine running, push clutch to floor put transmission in first. wait 9-15 seconds, then let up 1" on the clutch pedal and then put car in R.
If it grinds and your clutch( freeplay) is adjusted correctly your pilot bushing may need replaced.
It can be binding on the main shaft, vice allowing it to freewheel and actually stop. This can also make noise as the main shaft can be turning with the clutch disengaged. sometimes the drag/ load of the clutch being engaged when in Neutral can stop the noise.

Maye I missed something. not sure I understand 100%what your exact issue is but that's what I am thinking
 

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It is possible the TOB isn't seated in the fork correctly, this usually causes the noise to go away when there is any pressure put on the clutch pedal.
 

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Good point TAZ, the T/O bearing will go on with the lip between the clip and the fork, but both the clip spring metal and the fork go inside the groove on the T/O bearing.

Mine came with instructions illustrating this.
 

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Discussion Starter #10
Gets confusing with different ways to describe the problem.
New TOB, pilot shaft bushing.

I was doing a little research yesterday on the position of the TOB in relation to the clutch fork and like TAZ said there is a possibility it was position wrong. I just dread climbing underneath the car and ripping out the transmission.

When in neutral and the clutch pedal is to the floor I do not hear the sound.

When I take my foot off of the pedal and pedal is at its highest position that when I hear the sound. Its not just a slight noise it changes the sound in the car, but not to the point that I wouldn't drive it down the block.
 

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You may be able to look in through the fork hole in the bellhousing with a good narrow beam flashlight to see if the bearing is installed correctly. As Ruppert said, the fork and the springy clip should be in the groove in the bearing. If the spring is behind the bearing, you need to pull the trans and reposition things correctly.
Once you are sure the bearing is in correctly, if you still have the noise in the positions you are describing, it almost has to be the input shaft ball bearing in the trans.
 

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I HAVE A SNAKE Camera I got at HF. Suggest you acquire a better one and make sure the camera eye is small so you can get it in there and see.
you can also check your free play with it.
I'm thinking your TOB might be touching the clutch fingers.. maybe
 
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