Jensen Healey clutch problem

[TOPTON]

I have a 1974 JH with the standard fitted 2.0 lotus twin cam engine and getrag 5 speed box. 12 months ago when I acquired it, it had not turned a wheel for 12 years or so.
One of its many problems was the clutch, the pedal felt like it was doing something (as in foot pressure needed) but the clutch was not engaging.
I stripped out the gearbox and found what I thought was the problem, the thrust bearing was super tight on the shaft. I freed this up and rebuilt the car and it worked fine.

Now after not being used for 4 months, it has happened again. Only this time, through the bell housing hole where the clutch lever enters, I can clearly see the thrust bearing moving in and out when the pedal is pressed. I can see the fingers on the pressure plate moving with the bearing also. But the clutch plate is not freeing up.

I have tried bump starting the car in gear with my foot on the clutch, but it stalls as I brake to a stop.



It seems to me that the clutch plate is stuck to the flywheel and pressure plate. Anyone ever heard of this happening ?

[Mopar440]

Fairly common I think. Ask the question on the JOC forum, plenty of knowledgeable J-H people there:

http://www.joc.org.uk/phpBB2/index.php

[NigelStn]

I seem to remember freeing a clutch off once, by jacking the rear axle off the ground, starting the engine, so you have one or two of the rear wheels spinning, then standing on the foot brake while the clutch was depressed

[dpp]

Used to have this problem with a Humber Hawk, put the back axle on stands and start the car in gear then rev the engine to spin the wheels and stamp on the brakes hard.
Hopefully the shock will free the stuck clutch, it always used to work for me.

[dpp]

Looks like nigel beat me to it 8)

[droopsnoot]

I used to have similar trouble when laying the Sportshatch up over winter - the compound of the friction material must be such that it corrodes onto the flywheel face. I tried a number of methods of splitting it, but as the car was laid up over winter while the tax was out I couldn't run it up the road and try to shock it free. The only way I could free it was to remove the gearbox and clutch cover - at which point it would come away really easily, annoyingly.

One suggestion from a mate is to start the car and leave it to idle and warm through, perhaps for as much as forty minutes to an hour. The idea is that the differing expansion rates of the flywheel and friction plate ought to free it off.

I got around the problem by pressing the clutch pedal down and inserting a small block of wood to keep it down, so the friction plate wasn't against the flywheel while laid up. I wondered whether it would stress the clutch cable but the guy who suggested it said not - he did explain why not, but it went over my head.

[TOPTON]

Thanks so far guys.
After doing a bit of googling, one suggestion from a USA MG owners site was to jack up the rear end by the diff, put it in third or fourth, keeping foot on the clutch and drop the jack down fast. I have tried this and all I got was wheel spin and then a stall when I braked to a halt.

Maybe, as suggested above is to run the engine for longer and hotter and try again. But I think its looking like gearbox out time again.

Of course the solution for it not to happen again is to use the car more often. I think the main problem was the last time it was used, we got caught out in torrential rain on the way home and in was put straight in the garage and not touched again for 3-4 months

[bnseven]

I had this with a spitfire that had stood for about 10 years, tried all the jacking up and hand brake methods to no avail. In desperation and to avoid getting the box out I warmed the car, pushed it out to the road facing down a hill, started it in first and drove off. Foot permanently on clutch but changing up without the clutch. Got it into top and after about a mile the clutch released and all was well.

If you have access to a quiet lane it might be worth a try.

[TOPTON]

bnseven said:

I had this with a spitfire that had stood for about 10 years, tried all the jacking up and hand brake methods to no avail. In desperation and to avoid getting the box out I warmed the car, pushed it out to the road facing down a hill, started it in first and drove off. Foot permanently on clutch but changing up without the clutch. Got it into top and after about a mile the clutch released and all was well.

If you have access to a quiet lane it might be worth a try.

I'm going to give this a go at the weekend. I will update on explosive gearbox or a fixed clutch.

[TOPTON]

Well what a nice surprise. I warmed the car up for 20 minutes or so and then took it for a drive, starting it in gear to bump away. Once running it only took about half a mile with one gear change into second to free off.
It is now sorted and running spot on...Thanks chaps

[Perseverant]

Had this problem a few times. Often just starting the car and letting everything warm up does the trick when the heat gets to the clutch and gearbox. If you have space, another trick is to start in gear and drive with your foot on the clutch - I'm lucky in having a quiet road outside for such nonsense. On the other hand, a Moto Guzzi I restored a few years back had a twin plate clutch that was SOLID and required some work with old tea knives to unstick it. A good scrub with emery cloth and it worked fine!

[Willhire89]

The solution you have used successfully is the way to solve this - all this stuff about dropping if off jacks and braking will ultimately break something as the load comes back up the drivetrain.

The sympathetic (mechanically) way is driving along with the clutch down accelerating and decelerating in second and will soon free it off.

These engines seem to be susceptible to this - mine did it every time it was left for a month or so

[grumpy52]

If you warm the engine through very thoroughly then take it for a drive it tends to free off within a mile .
Happens more with older spec clutch linings .