26 replies to this topic

[TOMMO0302]

Hi guys & gals,

I bought a 1977 Mini saloon a couple of months ago with 1275 metro lump. Planned on getting it all set up and serviced when i got some money but before i could arrange that i lost drive going round a roundabout......i.e all forward gears and reverse could be selected, rev engine and nothing (drive wise). Obviously had to call out the RAC and he looked under the bonnet and got me to depress the clutch a couple of times to check the slave cylinder operation, i did'nt ask but guessing it would have been working hence the diagnosis of 'clutch dead'.

In hindsight, i should have done some research/got a second opinion but i didnt and purchased a clutch kit and set to work changing it....coming to the end now and realised that n/s wheel hub nut is loose (no split pin present) so im thinking that the driveshaft is'nt set properly in offset sphere joint.....

.....i am now thinking that what happened going round that roundabout might not have been the clutch failing, rather the hub nut working itself loose enough to either cause the driveshaft to move out as well or rhubarb the splines?
A) Does this sound feasible and
B) Would this happening give the same/similar symptons to the clutch going?

Any ideas?

[mattpink]

Usually get a progressive amount of 'slip' when the clutch is on its way out, rather than sudden failure - so I reckon you're right, and the drive shaft is probably hanging out of the CV joint.

[TOMMO0302]

You would'nt believe the troubles i have had replacing the clutch either!!Infact, being Mini Enthusiasts im sure you will.....firstly, puller stripped threads in clutch hub thing(never did work out what it was called but pic below):

so had to remove engine to get clutch/flywheel off taper, then sent above part away to be re-threaded which got 'lost' in post for 2 weeks, thank you RM.

Hey ho, at least i learnt some new procedures......im actually at the stage of bleeding the clutch and it does'nt seem to want to, by that i mean no matter how many times i depress the clutch there is always air present (using one way valve on end of hose and even tried tightening and loosening bleed nipple) so thinking air is entering the system somewhere along the lines, any ideas on locating offending area or does the dust cap on end of slave cylinder actually create a seal as i think this was'nt quite on properly to be honest after reassembly.

Cheers

[Dan]

Sometimes it can take ages to bleed a clutch through. Try leaving it with the pedal held down by a block of wood braced against the crossmember overnight, then bleed it again in the morning. Or get an Easy-Bleed, they really help by forcing loads of fluid through.

As for your driveshaft, how tight the CV joint nut is doesn't effect how securely the driveshaft is inserted into the joint. That's held in by a circlip. If the nut is loose it's just moving in the driveflange. Could lead to a disaster but shouldn't cause loss of drive, if the wheel didn't actually fall off then it would still be working (but it must be fixed obviously). I doubt it could move apart far enough for the spline to seperate without the wheel falling off. The spline could have been damaged by this though as you suspect which would lead to a loss of drive.

[Guess-Works.com]

have you looked at the pot joints on the gearbox ?

[Purple Tom]

I had exactly the same problem when putting my Clubby back on the road after the engine rebuild.

It turned out to be a lack of grease in the pot joint, which was in turn stopping the CV joint itself from sliding in and out of the pot (which it has to do to compensate for the suspension travel and the driveshaft moving in and out as the suspension moves).

The main problem though was a weak circlip on the inner end of the driveshaft, meaning that when the joint was stiff (due to the lack of grease), the movement of the driveshaft pulled the shaft out of the joint rather than moving the joint.

Does that make sense??

The remedy was quite straightforward - remove the pot joint, re-boot and re-grease, and fit a new circlip to the drivehaft, which comes as part of the boot kit. Job done - and it costs about £8.

[TOMMO0302]

Morning all,

Guessworks....have'nt had chance yet, will do so tonight.
Minis84.....Yeah that all makes sense, however, the wheel hub nut was loose prior to engine out job which is why i think it *could* have been the cause of all my problems in the first place - no drive. Theres plenty of grease in there i know that much at present

Next step.....remove driveshaft tonight and see what i'm dealing with, thinking i might need new driveshaft and/or pot joint

[Grayedout]

I suggest get a relative or friend to get in the car....start it...put it in gear and slowly raise the clutch while you, standing at the side, watch to see what is spinning !! If the drivshaft has failed in some way then the pot joint will spin freely.

Also look to see if both pot joints are still snugly pushed into the gearbox on each side.

Do the simple checks before diving head first into any more major dismantling !

[TOMMO0302]

Good advice,

I do seem to do that quite a bit!

What i can also tell you is that the driveshafts currently spin independantly of each other....i was trying to tighten hub nut with opposite front wheel on ground last night for resistance but driveshaft just spins- so i guess it must be either a) not sat in the pot joint properly or B) the splines are stripped???

regarding the pot joints fitting snugly into the gearbox....could this have also been a cause for my original drive failure or is this just something that might have happened in engine-out process?

[Purple Tom]

if the pot joint had come out of the gearbox you would notice a large pool of oil under the car, as the pot joint acts as part of the seal for the output shafts.....

I'm still gunning for the worn circlip causing the problem )

[TOMMO0302]

Haha, big pool of oil underneath my mini.....nothing more than normal!!

Im hoping for that as well but unfortunately this whole project has turned me into a bit of a pessimist....when nothing seems to go right! But i will soon become the optimistic again when she's back on the road

[Purple Tom]

I think the Mini is just doing what all good Mini's do, keeping you on your toes! Good luck!

[Dan]

You lost drive going round a roundabout? And now the wheels are independant of each other? Did you have anything apart other than the clutch when the engine was out to check it? Could be a broken diff pin.

[TOMMO0302]

Not apart no, the usual things as per the Haynes B.O.L

but tonight i have had the driveshaft out and i am including pics of what i think Minis84 was referring to as a "worn circlip" haha...you'll see why im laughing!

Im also including a pic of my driveshaft and driving flange (i think) as im at a loss as to understanding where the circlip should go and its purpose.......as i now see why you were saying that the pot joint would'nt come out the driving flange Dan (about 2.5" as opposed to 5mm maybe due to hub nut loosening)

....hmm?
Remnants of the circlip - i previwed this and essentially its just in lots of bits!! Just incase you thought i was ataching a pic of slugs or something?

Driveshaft

Drive Flange


If its any help to diagnose the problem....i was driving down the M23 from London, basically long time in 4th, came off the motorway, stopped at lights, pulled away maybe 10 metres and drive just went!

[Dan]

The picture you've labelled driveshaft is the inner member of the pot joint on the end of the driveshaft and the picture labelled drive flange is the outer member of the pot joint. Both seem fine except that there should be 6 1/2" ball bearings located between the two in those lobes which transmit the drive from the one to the other. There should be a rubber gaiter holding the assmebly together. I think you may need some new pot joints!