Throwout bearing failure question

[70Challenger440]

I am starting this thread for an older friend.  He has owned his car for many decades. yet has always had trouble with the throwout bearing failing. Any insight or suggestions ???

[Mr Cuda]

The car is suffering from a lack of free play in the pedal linkage.
Either the clutch fork doesn't have a spring to the bellhousing to hold the linkage tight, or there is a problem with the overcenter spring under the dash.
Another possibility is that the clutch had a diaphragm style,  which removes the overcenter spring.
Further down the list is wrong parts, i.e. different pressure plate style,  tall throwout bearing hub. 6cyl bellcrank.
Really anything that requires more pedal travel to release,  than it's designed for requiring clutch adjustment to be "tight".

But the upshot is, the throw out bearing is spinning against the clutch fingers while running. It shouldn't.

[70Challenger440]

I would like to mention the clutch  has always been correctly adjusted with the 1.5" of freeplay.  It does also have the return spring still and has never used a diaphram clutch.

[71GranCoupe]

Have you removed the inspection cover and checked the bearing and see what it is doing when running and in neutral?

[lahatte]

This is probably not the issue, but is it possible that the bearings aren't getting greased when installed?

[Mr Cuda]

I would like to mention the clutch  has always been correctly adjusted with the 1.5" of freeplay.  It does also have the return spring still and has never used a diaphram clutch.

And a return spring from clutchfork to bellhousing?
There has to be a gap from throw out to pressure plate  fingers.

[Dmod1974]

Is he resting his foot on the clutch pedal when driving?  Does he keep the clutch pedal in the whole time at stop lights or in traffic instead of shifting to neutral? 

If it truly has that much free play and the correct parts installed it sounds more like operator error....  Even just lightly resting your foot on the pedal enough to take up that free play will make the bearing fail rapidly.  It's not meant to be under continuous load.

HOW are the bearings failing?  Noise, burnt up face, rollers falling out, grease slinging past the seal, etc..  Got any pics?

[70Challenger440]

"Is he resting his foot on the clutch pedal when driving?  Does he keep the clutch pedal in the whole time at stop lights or in traffic instead of shifting to neutral? "


Definitely no.... i appreciate all the questions and responses. He is an experienced clutch driver. Only this one clutch car of his has this issue. 

[cuda hunter]

HOW are the bearings failing?  Noise, burnt up face, rollers falling out, grease slinging past the seal, etc..  Got any pics?

[70Challenger440]

HOW are the bearings failing?  Noise, burnt up face, rollers falling out, grease slinging past the seal, etc..  Got any pics?

I cannot provide bearing pictures, nor I have seen the bearings. (work always done by shops). I can tell you each time this has occurred, it's noticed by the bearing starting to make a whirring sound which progresses to a more harsher grinding sound.

Since you mention various things like ... burnt up face, rollers falling out, grease slinging past the shield, maybe you can instead state what each would signify, for when he goes to the next shop and shows them  this thread. In fact any possibilities mentioned are appreciated and might end up pushing the garage in a direction they might not of otherwise thought of.

[torredcuda]

Has the input shaft been inspected for wear, damage, burrs etc.?

[dodj]

Is there a possibility of the wrong clutch fork being installed? So the throwout bearing is getting somewhat side loaded? Just trying to think of anything.....Or maybe the wrong pivot bracket attached to the bellhousing?

[B5fourspeed]

The 18 spline takes a different bearing than the 23 spline.I made the mistake because my 440 is mated to a 23 spline.The 18 spline bearing will have play in it on a 23 spline.I forgot to mention I had a 23 spline when I ordered the bearing.I just said I was running a 440.

[MoparLeo]

Your friend should always request his old parts when having something replaced.
This is actually the law in California if requested, the shop must give the old parts to the owner. This is so that not only does the owner know that the part was replaced, but he can also have the parts inspected by a third party to verify the problem.

[Mixup7071]

I had the same problem every year and a half or two years my bearing would go out I replaced bearing and clutch assembly, I did it a few times I had shops do it, the last time I found a guy, he even lived close to me, told him my problem be asked me if anyone took the flywheel off and had it resurface I said not that I know of, I would take sandpaper to it but that's all, he took it off had it resurface new clutch assembly and bearing that's been six years ago still no problem.  knock on wood