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MG MGB Technical - Throw out bearing gone

My shop confirmed my throw-out bearing in the MGA is completely worn out, with only 12,000 miles on the new drive train. I am wondering if such premature wear has been a problem with others running the Hi-Gear Ford 5 speed?
I have run a warmed up 18V using an early B flywheel and standard B Borg and Beck diaphram clutch. I do not ride the clutch peddle or hold it down for more than the minimum (Do I sound defensive!). No alternative but to R&R the engine and trans right? Thanks Guys.
Steve
Steve Meline

I had the same problem and I was told a few thinks:
- There was a quality problem with some bearings (Borg and Beck?)
- When sitting at a light or stopped, through the trans in neutral and don't hold the clutch in
- There are ball bearing throw out bearings, but they wear out faster

I think there must be other cars that use more modern bearings that could be grafted in, but the shape of the contact surface is not popular

That is all I know
Frank Baker

12,000 on any pilot bearing in not much. I would wonder if there may be the slightest of alignment issues so there is more load on the bearing.

Never had one go out in an MG. Had one go out in a Subaru, but then, it had 150,000 on it.
Bruce Cunha

Steve,

Are you sure the hydraulics are in good order? If the clutch was not releasing properly then it could force the bearing into contact when it shouldn't be. If you are driving in a manners that shouldn't hurt the bearing it is either dodgy parts or dodgy hydraulics.

Iain
I D Cameron

What are the symptoms? A worn but working release bearing makes a noise when the pedal is pressed and you can usually feel vibrations at your foot. A broken bearing means no resistance to pedal pressure, eventually pushing the piston out of the clutch slave and spilling fluid. Other symptoms are usually hydraulics, or wear at the master linkages, or worn friction plate.
Paul Hunt 2

Steve,
At least you got 12 K out of yours. I put a Ford 5 speed in by 76 MGB and can't get the clutch to disengage. Have switched out the master, the slave, the hose, spent 100 hours (seems like it) bleeding the system still no luck. Do not seem to get any travel of the pin at the slave cylinder (no more than 1/4"). Have tried different length pins at the slave. Now about ready to cange the master cylinder rod length. I am running out of options and friends to encroach on. I have a 1970 GT that has 1/2" of travel at the slave. I know its hydraulic but this is getting ridiculous.
Mike
Mike Lang

Mike

1. Use an Eezi bleed as well as an assistant, and make sure the tyre is WELL pumped up
2. Use a large screwdriver to push in piston in the slave clinder as far as it will go when bleeding. start by levering the piston in and hold it there when you release the nipple on the first push of the pedal.
3. Then try a few normal bleed cycles
4. If necessary repeat with the lever

This has always worked for me on cars that refuse to bleed like this.

Good luck
dominic clancy

As a varriation on what Dominic has said you could use what I look upon as the Paul Hunt method of bleeding the clutch.

Firstly about 10psi max in the tyre. No more or it will all happen too quickly and make a mess. Unbolt the slave so it hangs on its flex line. This makes the flex line port the highest point on the slave. Put a large cable tie end to end round the slave.This stops the piston popping out. (Although at 10psi it should not.) Rig up the Eezi Bleed so that it will push fluid into the bleed nipple. Open the bleed nipple slowly while some one watches the level in the master.

If you use this method and the clutch still does not work it is not a bleeding problem.

Have you spoken to Hi-gear?
David Witham

Well we finally acheived 1/2" of travel by using a longer slave pin and a longer master cylinder pin. That's the good news. The bad news is that the clutch still won't disengage. I guess I am pulling the motor and trans again.
Mike
Mike Lang

Mike, the clutch disk may be sticking to the flywheel. You should try some impact type things before you open it up just to look. Like with the brakes on and in 4th gear, clutch in, hit the starter or rock the car back and forth. Don't do anything unsafe, of course.

Maybe you have tried this already, and it is time to look inside.
Tom

This thread was discussed between 26/09/2006 and 28/09/2006

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