Throw out bearing or input shaft bearing - how to test in hydraulic clutch?

[idosubaru]

Noise goes away when pedal is pressed in. So it's the throw out bearing or input shaft bearing.

 

How do you test this in a hydraulic clutch 2003 Legacy sedan H4?

 

In a clutch cable you loosen the clutch cable and see if it goes away or not right - if it goes away then it's the throw out bearing.

if not - it's the input shaft bearing.

[Toadspit]

I know I am the new guy here but it sounds to me like you already figured it out. When the clutch is pressed the throw out bearing is pressed up against the little springy fingers of your pressure plate and it is spinning at current engine RPM. The pilot bearing on the other hand is pressed into the middle of your flywheel and is spinning at current engine RPM all the time. If the noise is consistent my money is on pilot bearing but since it only screams with the clutch pressed my money is on throw out bearing. Have a great day and good luck 

[Toadspit]

Also I might add (judging solely by post count) you likely have already read on this forum that if you are going to do one you might as well do it all. I just did a full clutch job on my Subaru over a throw out bearing and after pressing out the old pilot bearing i was very glad i did. Pressure plate had some abnormal wear also but the clutch disk still had some of the slots left on it .

As hard as that stuff is to get to it is best to replace it all while you are in there. Then if the gods of good karma smile upon you it will be a long time before you have to go back inside.

  P.S. Don't skimp out and  not replace the little clips that retain the throw out bearing. $5.00 and it is the weakest link in your clutch system

[Gloyale]

Noise goes away when pedal is pressed in. So it's the throw out bearing or input shaft bearing.

 

How do you test this in a hydraulic clutch 2003 Legacy sedan H4?

 

In a clutch cable you loosen the clutch cable and see if it goes away or not right - if it goes away then it's the throw out bearing.

if not - it's the input shaft bearing.

 

Low grumble??   That would be Input shaft bearings

 

High pitched "chirping"  would be Throw out......

 

The throw out, the noise should stop or change with just a slight pressure on the pedal....

 

If the noise doesn't stop until you actually put the clutch in.....fully disengaged from enigne.....then that's the Input shaft bearing.  Fix the trans before it grenades and you will get alot more life out of it.

 

  P.S. Don't skimp out and  not replace the little clips that retain the throw out bearing. $5.00 and it is the weakest link in your clutch system

 

While I agree best to replace......but honestly they don't matter.  They just hold the bearing in place during install.

 

I pull apart clutches all the time with none......and I've assembled my wheeler without them several times....no issues.  They are just for install.

[idosubaru]

Not sure on grumble/high pitch, looking at friends car Wednesday.

 

When in neutral without pushing the clutch pedal, is it only the input shaft that's supposed to be spinning?

Technically the throw out bearing shouldn't be spinning unless it's midadjusted right?

 

So noise while idling in neutral can't be the throw out bearing?

Pilot bearing?  When is that spinning?

[Gloyale]

When in neutral without pushing the clutch pedal, is it only the input shaft that's supposed to be spinning?

Technically the throw out bearing shouldn't be spinning unless it's midadjusted right?

 

So noise while idling in neutral can't be the throw out bearing?

Pilot bearing?  When is that spinning?

 

Well.......The Throw out can ride just barely against the PP fingers even with clutch out/neutral.........that's the chirping.......moving the clutch pedal or fork just a bit should change or eliminate the chirp if it's the throwout..

 

Pilot bearing spins when clutch is in, sitting still.   Engine spinning, clutch disc and input shaft stationary.........so that would not be the issue you'd hear it with clutch in.

 

Pretty much seems to be the input shaft......If it grumbles.....and doens't stop until the clutch is derpessed (disengaged) that definate diagnosis.

[idosubaru]

Thank you much GLoyale for clarifying that.

 

On a hydraulic clutch is there anyway to "move" the clutch fork to make sure it's not the throw out bearing partially engaged?  It doesn't sound like it is but I'll test it if there's a way to do it.  I see other threads with "noise goes away when clutch pressed" - where folks say replacing throwout bearing fixed it.

 

Or the noise - grumble/chirp - is the most telling?

[Fairtax4me]

Pilot bearing only spins when the clutch is disengaged, which is pedal down.

 

As said before, applying only light pressure to the clutch pedal will seat the release bearing against the pressure plate and should make any release bearing noise either increase or stop.

 

If the noise does not go away until the pedal is fully depressed, that would be input shaft bearing.

[WoodsWagon]

On a hydraulic clutch is there anyway to "move" the clutch fork to make sure it's not the throw out bearing partially engaged?  It doesn't sound like it is but I'll test it if there's a way to do it.  I see other threads with "noise goes away when clutch pressed" - where folks say replacing throwout bearing fixed it.

Yes, grab the top of the release fork and push it firmly toward the slave cyl. The cyl will slowly compress.

[idosubaru]

Thanks, will do that Wednesday.