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MG MGB Technical - Heavy clutch

Hi:
I am new to the MGB list (stay on the TD-FT side) but need help.
I have just rebuilt an MGB for a friend - refaced flywheel, new cluch & disk, throw out, etc. Old clutch hydraulics. The clutch is a bear to push down . . . I am just able to do it. Any thoughts??
Godspeed in Safety Fast
Jc
John Crawley

John. You should be able to push the clutch down with your fingers.

Problems which could cause a heavy clutch, from the top:

Wrong, excessively heavy clutch pedal return spring.

Clutch pedal binding on its pivot point.

Clutch pedal binding on the master cylinder pushrod/clevis pin.

Master cylinder binding internally.

Clogged hard line not allowing fluid to flow from the master cylinder through the system.

Clogged flex line not allowing fluid to flow through the system.

Binding piston in the slave cylinder.

Slave cylinder pushrod binding on the clutch fork/clevis pin.

Clutch fork binding on its pivot bolt.

Throwout bearing binding in clutch fork and not making full contact with pressure plate.

Wrong/incorrectly manufactured pressure plate.

Wrong/incorrectly manufactured clutch plate.

Clutch plate installed with wrong orientation.

One of the above, or a combination of them, should be your problem. A quick first test might be to recruit your friend to push the clutch pedal while you open the bleed nipple. If the pedal will easily go to the floor, the problem should be with the lower part of the system. If the pedal is still very had to push, there is a problem with the upper portion of the system which needs to be corrected before further trouble shooting can take place.

Les
Les Bengtson

If you put a "heavy duty" clutch in, the pedal will be heavy, although not as heavy as your discription reads. I mistakenly put heavy duty clutches in our MGB at first and found that besides the heavy pedal, the only thing a heavy duty clutch is good for prematurely wearing out the throw out bearing. Cheers - Dave
David DuBois

Thnx Guys:
I'll try Les's from the top down method of checking and see what I find. I'll let you know . . .
This new fangled hydraulic stuff . . . give me a chain clutch linkage like the TC or a good old fashon rod like the TF every time . . .
:-)
Godspeed in Safety Fast
Jc
John Crawley

Hi:
As promised . . .
The problem was FLEX LINE swollen shut.
I am fitting all new hydraulics anyway jsut to be safe.
Thnx again for the help . . .
Godspeed in Safety FAst
Jc
John Crawley

John. Glad you got it sorted and thank you for letting us know what you found.

Les
Les Bengtson

Hmm, that was an interesting thread. My clutch is heavy.

On the subject of pedal return springs - the two I have on mine - brake and clutch - are the same as the bonnet release spring.

I have two much smaller springs I bought a year ago. I can't remember what I bought them for, shame on me -but they may well have been return springs and were part of a big order, I simply have fogtten what they were intended for.

Those are much shorter and lighter, perhaps a couple of inches, or inch and a half, with the 'hooks' at the end being separate from the main spring body, instead they are trapped inside it.

Should I be using these? The reason I didn't is because they didn't look up the job.

Regards all,

Liam
Liam H

Liam,

Your springs sound to me like the throttle return springs on the carburator linkage. They route from eyes in the linkage to holes in the heat shield.

Just my humble opinion from someone with less experience than others on these cars.

dave
Dave Braun

Liam. The original springs are made of .062" wire and have 28 coils. There is a large semi-circular hook, oriented back into the coils, at the end which attaches to the pedal and a smaller semi-circular hook, oriented outside of the coils, to attach under the dash. The example I have to hand may have stretched somewhat. With the coils compacted, it measures 1.835" overall length. In current form it measures 2.535".

The current springs suppled by Moss Motors (USA) are made of .067" wire and have 28 coils. All of the coils are touching and measure 1.882" overall length. Orientation and description of the hooks are the same as the factory original.

The slightly thicker spring wire may give a slightly harder pedal effort. The stretching of the original spring, either factory or happening over the years, will also reduce the pedal effort. Thus, I would expect a slightly heavier pedal effort if new springs are installed. Whether this would be objectionable or not is an individual impression.

Hope this helps. Les
Les Bengtson

Liam,

Dave is correct. Those are throttle return springs.

iain
I D Cameron

This thread was discussed between 11/04/2007 and 25/04/2007

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