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Hell of a Monday - Thrust Bearing gone!

M

mmw68

Member
So Iam driving the mustang on Saturday, and I hear a noise that sounds like a 2x4 across fan blades every-time I push the clutch in. So I pull into a gas station and they let me put the car up on the lift. We where able to move the Harmonic balancer forward/backward about a 1/4 inch!

Dropped it off to my trusted Mechanic this am, and waiting for a phone call.

Hell of a Monday. :rant
 
A loose bolt that holds the balancer.Hope that oil seal is not damaged. :confu
 
Does not sound as simple as a bolt...... If the balancer is moving back and forth and you hear the noise when you push on the clutch...... Sounds like a bad deal.... Did you check the oil?
 
Plenty of Oil! ;) I got a quick VM from my shop, and It might not be so bad, I hope to get over there today to grab some details. -mark
 
It's not looking good... :rant

We have check a bunch of things, and we keep coming back to the Thrust bearing. So now Iam trying to decide what to do - entire engine rebuild?
Just buy a short block? Well - this is going to eat up the rest of my budget! ;(
 
If your running a hyd throwout bearing, a improperly adjusted one will cause the thrust bearing to wear and the noise your having.
Even the standard mech clutch linkage not having enough freeplay can cause this damage also.
 
I sure hope, a few days of driving on a tight adjusted clutch would not do this. If so It's been a expensive lesson for me. :shrug
 
Sorry to bear bad news... But yes it could have.
The over extension of the throwout bearing causes excess pressure on to the flywheel and crank.
While it may not seem like much to your left leg, Leverage from the linkage will easily double the pressure applied to the plate fingers which
can only move so far before it is transfered to the crank.
 
I had a chance to go buy Ike's Tranny shop this morning, and discuss what he found. I do not think it the engine problem now. Here is what is going on, and took the car for a drive today as well. Engine sounds great while in gear, and at idle.

He did the following:
1. Shortened drive shaft
2. Replace flex plate

Looking at the picture of the old one - something is rubbing! I am not sure if you can see this in the picture, but the marks towards the top have sliced all the way thru the plate.

The noise now only happens when you push the clutch pedal in. Starts about mid way thru the push, and as long as the clutch is in - or the pedal is pressed down, you get this squeak, squeak, squeak, vey repetitious, like something is hitting when the spinning is going on. The volume of the squeak has gone down about 50% with these new changes.

He is going to work on it a little more today, but I feel this is good news!

flex_plate_old.jpg
 
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If you really have that much crankshaft end play you need to stop running it and pull it. You're only risking/causing more damage and expense.
 
I agree, and I will pull the engine if that is what we decide it is. I'll post up some measurements when I hear back from the shop.
 
When the crankshaft moves fort and aft , I think your No3 crankshaft bearing is worn on its flanks/side . :rant
Here some pics :
 

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The 3rd main bearing has a different shape and I think this bearing holts the crankshaft inplace regarding fort and back play.
see pic : its different then the other bearings.
 

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Normal end play should be no more than .004-.008". If it is moving anything close to that 1/4" statement, he's got way more than just some bearing damage. Crank and block are probably shot too. It'll run that way..for a while so don't let yourself be fooled. That's why I say pull that thing and take a look at the bottom end before you really do need to invest in a whole new shortblock.
 
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