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MG Midget and Sprite Technical - Thoughts please on a non engaging clutch

Last night I was unable to engage the clutch - lots of clanking and grinding etc. The clutch has been fine UNTIL I hard to brake fairly sharply on the way to work - its was slipping but seemed to work until I parked up and then went to leave!!
Once I got recovered home I seem to have a couple of issues - any advice welcome.

New gaiter fitted to the arm side - seeping/wet with black oil - deffo not from slave cylinder - other blank appears clean on first inspection - would this be 'normal' engine oil past seals and gaskets getting caught up?

The lever from the slave appears to fully extend and still the gears will not mesh - does that sound like the clutch bearing?

I recently changed the fluid in the clutch system - 3 months ago - in reservoir oil is quite dirty - would this point to seals going in the master and not giving full pressure/fluid to the slave?

I'm not against pulling the engine as such - going to be a logistical juggling act in the garage - but perhaps one of you enlightened members might be able to point me in the likely cause/solution!!

TIA

Dave
D Price

I wonder if you have a carbon release bearing? It is not unknown for these to wear down until the metal carrier contacts the clutch. Even worse, some cheap replacement bearings may shed the carbon pad.
Mike Howlett

If the clutch arm is being fully pushed in by the slave cylinder and the clutch isn't working then it must, unfortunately, be a problem with the clutch itself.

I have recently removed the engine from my Sprite, in a single garage by myself. You will certainly need a hoist but after an excellent tip from this site I positioned the lifting chain with three times as many links to the back as opposed to the front. The chain was fitted to the rocker cover bolts. As I lifted the engine it tilted at a steep angle and cleared the tunnel/heater support and the front crossmember.

Replacement though is a two person job. Using the same method with the chain I found the rear of the gear box needed lifting to fit into the transmission tunnel. My grandson had to crawl under the car with a bottle jack whist I worked the hoist.

Unless your hoist has good wheels and is manoeurable you will have to leave the car on its wheels, on a flat surface since you will have to push it backward and forwards.

The best of luck

Jan T
J Targosz

Jan, next time do try putting a trolley jack under the rear of the gearbox. Then, as you lower the engine the gearbox trundles rearwards on the jack wheels. As it nears the opening in the tunnel you reach under and give the jack handle a couple of strokes and it lifts the tail of the gearbox into the tunnel as you nestle the engine into place.
That said, involving your Grandson in some hands on garage work is no bad thing and help in such an important way shows him that he is clearly highly valued!
GuyW

Carbon release bearings can pack up really suddenly. It does sound like that. Original carbon bearings seemed to be much better and lasted for thousands, if not tens of thousands of miles. The carbon in new ones seems brittle and can very quickly disintegrate as opposed to a steady wear.

With a torch, or endoscope if you have one, it is possible to get a view inside the bell housing which may help. A few photo shots with a mobile phone sometimes helps too as you can zoom in on the photo for a closer look.
GuyW

To lift the gearbox tail into the back of the tunnel I get it partially in and then put a bit of rope through the gear-lever hole and around the box tail.
I can then lift it as the trolley is pushed back and it avoids any thing/ body being underneath.
Does need an assistant.

R.
richard b

Thanks for the advice so far - going to see If I can get a look inside the housing and see whats what
D Price

Hard to see what the fault might be!! Taken from the LHS - opposite side to slave cylinder

D Price

It looks like the clutch release bearing hascompletely disintegrated.
you can see the back of the clutch cover on the left. The bearing should be in the space inbetween, The remains
Bob Beaumont

It looks like the clutch release bearing has completely disintegrated.
You can see the back of the clutch cover on the left. The bearing should be in the space inbetween. The remains of the bearing are the circular items in the middle of the photo.These are the 'ears' of the bearing in the clutch fork

The engine will need to come out to replace it I am afraid
Bob Beaumont

Replace with one of Alan Anstead's roller release bearings. It will outlast you and the rest of the car!
GuyW

Never seen one that bad !
Need to check the fork arm for roundness where the bearing sits as it doesn’t look very round in the pic?

I would replace the cover plate as the pressure pad looks rather worn/ grooved ?

R.
richard b

The "ears" of the circular carrier that the carbon bearing sits in have broken off, so it's not just the carbon that has disintegrated. If you had to do an emergency stop, did you stamp on both the clutch and brake pedals together? It's almost involuntary to do so in an emergency. I wonder if that would destroy the carrier like that - or maybe it was just a faulty or poor quality part.
GuyW

One of the problems with replacement clutches is the cover plate. The plate the release bearing presses on has quite square edges as shown in the photo. The genuine AP or original Borg and Beck (not modern versions) has a rounded off plate with a bevelled edge. I think this may help reduce wear to the carbon thrust. Alan's roller bearings avoids this of course.

Bob Beaumont

Guy - thats exactly what happened - tractor came out of farm yard - high hedges and low car.....
D Price

One of the hazards of Devon lanes !
(I used to live in Somerset; and in Cornwall. Managed to skip on Devon 🤣)
GuyW

Hi Guy,

Hope I don't have to lift the engine again soon. It has been out twice this year! First time was to dump the totally ineffective rear crank lip seal and reinstate the original set up - much, much better and now to recondition the gear box. I note your comments re our grandson. I think interest in old cars skips a generation. Our son would sell the Sprite and put the money towards a new hybrid with a sophisticated sat nav. One of the grandsons though is desperate to do any work on the car. I don't know the age profile of Spridget owners but up till a year ago I had a 1955 MG TF and even though I am well retired I was the youngest at MG T series gatherings.

Jan t
J Targosz

So - oil drained, dizzy off, starter off - bits of the bearing visible!!, carbs off, exhaust off, wires off. Just realised that I should have fed the kids as SHMBO is away this weekend and back in 4 hours!!! Water and cooling next week with gearbox bits and then lift time!!
Its like being back in the RAF stripping helicopters down and back up again!!
D Price

Dave, as Guy suggests, I'd definitely replace the release bearing with a roller release version.
Bill Bretherton

Hi Dave,

Sorry to hear about your clutch, but at least you avoided the tractor!

I am in the process of decluttering and I have a couple of used clutches that have been under my bench for years. As far as I recall, neither of them had done many miles, but people more knowledgeable than me will know how to tell whether a used clutch is worth refitting.

The first two photos show what is in an AP Racing (Borg & Beck) box labelled HP1232. That's the number for an uprated clutch but I cannot guarantee that the friction disc and cover plate are what originally came out of that box (it was a very long time ago). But the friction disc looks to have metal in the friction material, suggesting it is a heavy-duty item.





Jonathan Severn

The second pair of photos show what came out of a Unipart box labelled GCC 115. I believe that is the part number for the clutch cover, though my box contains a cover, friction disc and two (?!) carbon thrust bearings.

If you are interested in any of this, I am open to offers because I really do need the space!

Jon (jonsantispam@gmail.com)





Jonathan Severn

This thread was discussed between 01/10/2022 and 02/10/2022

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