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MG Midget and Sprite Technical - Which Clutch To Buy

After 10 years of owning my 1500 I suppose Ive not done to bad replacing the majority of common wearable parts plus many others, the clutch finally gave up yesterday in the heat.

I normally buy parts from the usual online sources but last week was helped out by a local motor factor with some TRE's required urgently.

Are there any places to avoid when sourcing a new clutch or am I as good going to the local motor factor, if a new one lasts me another 10 years I'll be happy!

Tim Lynam

Tim,
if the TRE are First Line (green box) or Borg & Beck (dark blue box) and a 17mm socket/spanner fitted better then both companies are part of the First Line groups and I'd suspect, but don't know and haven't checked, that the items are made on the same production line.

What's this to do with a replacement clutch, well Borg & Beck, it's not the company it was. That's not to say there products are bad just that the usual suppliers and some (many?) motor factors might stock them.

Whether First Line / Borg & Beck also manufacturer for others to put their name on I don't know but a lot of old brand names remain, some bought and licenced out - so things change and what was a good, or bad, name previously might not relate to now.

Sorry I don't know with clutches and what and where to avoid or best to go to. If you're not buying from the local motor factor you could ask those that supply to Spitfire 1500 (other than the usual suspects).

The way many tings are at the moment you may have a limited select of what is actually available.
Nigel Atkins

Dont know about the 1500, but I bought a Borg and Beck for my 1098 a few years ago and it has been fine. It wasnt the cheapest on offer but I thought it was worth paying the extra. I think it was made in Poland or some other former eastern bloc country.

Trev
T Mason

Tim

That is good going on your clutch.

You could try seeing what new old stock - old Borg & Beck (not the new stuff that Nigel mentions), and the contents of old Unipart and British Leyland boxes - is available on a certain auction site.

I’d be tempted to check out the condition of your slave cylinder at the same time. If looking tired go for a genuine Lockheed cylinder (AP Caparo, now ‘920 Engineering’) from someone like PowerTrack: https://www.powertrackbrakes.co.uk/ (or a genuine AP Caparo/920 Engineering seal kit) but if working fine and not leaking leave well alone!

Cheers
Mike
M Wood

Thanks for the comments, the TRE's were First Line Group, looked similar to the last ones fitted but no grease nipple.

Good idea about looking for the old stock on auction sites, I'll have a search.



Tim Lynam

Tim

Do you want to say what you were doing before the clutch gave up?
Dave O'Neill 2

Tim,
something to bear in mind for future work, only recently there was thread (forget which) where I put about my discovery of the First Line / Borg & Beck TRE thread and nut being the rather unusual metric of M10 x 1mm (thread) (17mm spanner).
Nigel Atkins

Dave, well maybe I should expand a little more but not totally guilty!

I arranged a track day at Curborough initially for the Notts & Derbys MASC, but we also ended up having several MASC menbers from far and wide who were far more experienced.

After a horrible trip of only around 50 miles in the rush hour and heat down the A38 I arraved at Curborough safely parked up, went back to the car later only to find unable to get a gear.

Then a suggestion, remove the rubber mat, remove the carpet and low and behold enough clutch to crunch around the circuit several laps and a good day was had by all.

The car limped home somehow, but the carpet and mat removal worked a treat and saved the day! But I cannot blame Curborough for finishing off the clutch, thats my fault for keep leaving the job until "next winter"

Nigel the TRE was an imperial thread on the First Line ones I purchased which I never thought too much off at the time, just happy to get them in time for the Track Day.
Tim Lynam

That sounds like a hydraulic problem, or an issue with the release mechanism.
Dave O'Neill 2

Dave, You may be correct, the clutch has needed changing for sometime nothing drastic but its not 100%.

I did bleed it a good few months ago and it did reduce the occasional crunch going into reverse and it did seem better, but I have checked the fluid and it has not lost any fluid at all since the day out in very hot weather on Monday.

But please correct me if I am wrong, but under very hot conditions I pressume that any water in the clutch fluid will boil and reduce the efficiency of the clutch.

Under very hot conditions is it likely to have any adverse effect to the actual clutch.

After the car has been stood in the garage and cooled down after the last couple of days at the moment there is no issue changing gear, but Ive not tested it out on the road as yet.

Tim Lynam

For a relatively sudden, but still just a partial, clutch failure on a 1500 I would check that the clutch lever arm pivot pin hasn't dropped out. You can easily check if it's still there by poking a pointy type screwdriver up from beneath. If it goes in, then the pivot pin is missing. A temporary ( though long lasting) fix is to drop a bolt down into the pivot hole in the bell housing case. Something like a carriage bolt as the large head stops it dropping straight through!
GuyW

Thanks Guy, I will check the pivot pin is still there tomorrow.

Ive just attemted to take it out to see if its better now its cooled down, there is no problem selecting gears until you turn on the ignition and then try to select gear, there is only half an inch or so of pedal before it bites and its far too stiff and dificult to select gear with the engine running, but turn the engine off and it feels fine.

Tim Lynam

If what you are saying is that the bite point is way down near the floor, that could well fit with a missing pivot pin. They are an interference fit and do have a habit of dropping out. The release bearing carrier then moves and pivots against the edge of the cut out in the bell housing so it still operates, sort of. But only down near to the floor and it then doesn't fully disengage the clutch
GuyW

Thanks Guy, I do hope your right, that sounds much easier fix than pulling the engine & gearbox.

Just to clarify, are you talking about part no 26 in the diagram?



Tim Lynam

AHH, no! I thought yours was a 1500 !
GuyW

It's part 65, on that same image for a 1500 clutch
GuyW

65, pivot pin for the 1500 clutch release bearing carrier ?

GuyW

Sorry Guy, thats me not concentrating and picked the 1275 and not the 1500 clutch breakdown.

I will check part no 65, the clutch and gearbox are the main parts I have never touched other than bleeding the clutch, but I will have a look to see if that is operating correctly.

Thanks for your perseverance!

Tim Lynam

1500 Midget, hot weather (ie any temp above 25C). Beware of 'The Curse of the Bulging Red Hydraulic Hose'. Also a common problem with certain Lotus cars, too. When depressing the clutch pedal, a compromised (ie old) red hydraulic hose 'balloons', rendering the clutch partially or totally inoperable.
Just my pennyworth . . . .
J Thomson

Very good point and one I wouldn’t have thought of, I will check the red hose, it’s always seemed strange to why they used the red hose rather than fixed piping, but there must be a good reason?
Tim Lynam

It was outrageously hot on Monday. My car vapourised the fuel in all the feed pipes after shutting off every run.
Rob Armstrong

Yes, - clutch plastic pipe, - that's a good possibility too in this exceptionally hot weather. Good suggestion!
GuyW

Rob, it was crazily hot on Monday and several mentioned they experienced fuel vaporisation on the way home, no doubt not helped by driving it around a track at speed and high revs, the strange thing was the only time the clutch worked OK was going round Curborough but as soon as sat at lights going home the clutch was pretty non existant.

The red clutch pipe appears OK, but I suppose your not going to know unless you fit a new one and bleed the system.
Tim Lynam

Rob

Are you running carbs or injection?
Dave O'Neill 2

My first thought was flexible rubber hose, then I remembered the 1500s have the plastic(?) hose and didn't think they were susceptible - so I go along with that idea (now someone else has thought of it!). 😀

I'm also into often there can be a combination of problems causing an issue, by vast experience of this phenomenon, so also go along with Guy's pivot.

This heat also plays up batteries and electronics, so I wonder what error codes modern cars are throwing up.
Nigel Atkins

All looks ok under the car, slave cylinder and red pipe dry, but the long bolt in photo near the gearbox oil filling point has no securing nut on and easily pushes up and down, I presume nothing to do with the clutch not working but does not look correct. Can anyone please confirm what it is, I cannot work out which part it is on the breakdown to see if anything else missing.

Tim Lynam

Clutch pivot pin!
Looks like the original pin has previously dropped out and been replaced with that bolt dropped in. Being a softer material it may have worn and anyway looks undersized ( too skinny)

From the Moss diagram there is supposed to be a sleeve in there as well (part 66) so if that has gone too you may just have too much slack in the clutch release mechanism.
GuyW

Thanks Guy, I thought it looked far too big as against the parts breakdown, I will get new ones ordered and see if it is enough to take up the slack, should the correct sized pivot pin & sleive fit with the gearbox in the car?
Tim Lynam

Tim, TBH, I cannot now remember! I have an idea that the use of a random bolt like that is because to fit the correct parts one needs to remove the gearbox! Hence people do a temporary fix like that until next time the car is dismantled.

I hope I am not leading you to chase red herrings! Its a long time since I had a 1500. But I think another check is to see if you can rattle the clutch bearing carrier around, (Moss part 64) from side to side, with your fingers on the opposite end (area of the slave cylinder push rod) Obviously it shouldn't be too loose as excess slack in the pivot pin ( even the temporary one) will translate into less clutch release and therefore grinding gears.
GuyW

Guy, no problem I’m just being a whimp and trying to avoid taking the engine out, I’ve had just about every part off the car but always avoided removing the engine, but someone may come along and say it’s possible, I’ll soon find out!
Tim Lynam

Re. 1500 Midget (clutch bearing carrier) fulcrum pin.

I think the 'missing clutch pin' has always been a bit of a red herring with regards the 1500 Midget.
I have driven tens of thousands of miles, being unaware that my clutch pin was missing (it must have dropped out from its housing years prior).
The 1500 Midget (clutch bearing carrier) arm sits in a recess in the bell housing, the arm's pivot action works fine being held in the recess with no pivot pin.
Well, that was my experience of it.
J Thomson

Well that wasn't my experience. When mine dropped out it was quite apparent pretty well immediately that the clutch no longer disengaged properly.

Out of interest, if you were unaware it had dropped out, yet drove tens of thousands like that, how do you know when it did? Is that what is called a Known unknown, or perhaps an unknown unknown ?!
GuyW

Off topic, but I'm on injection. As soon as I got the ignition on again it was fine, but every start up the pump needed to fill the pipes (it sounds different)
Rob Armstrong

Update!

After fitting a new clutch, new slave cylinder and new clutch master cylinder and spending hours bleeding it, there's still sometimes quite a crunch selecting reverse and when the pedal is pressed and in gear, the engine does not appear 100% disengaged.

Along with the clutch etc I ordered the pivot pin as per photo and it did not seem obvious how to fit, the old bolt in its place appeared straight and not worn so decided to leave the new one out, can anyone please confirm how the pin is kept in place by the other two parts? No doubt it needs fitting from inside the gearbox but I hope I am wrong!


Tim Lynam

This thread was discussed between 20/07/2021 and 20/08/2021

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