Fierce clutch judder

[docevi1]

I've got a [url]Marlin Roadster|http://www.stefancarlton.net/index.php?menu=marlin&type=marlin[/url] which runs Morris Marina running gear, although for the most part it's standard BL.

In the past year the clutch has started to judder badly in 1st gear and reverse. I'd always used the car regulary to drive in traffic and whilst it did it, it certainly wasn't bad.

Recently however the car is getting undriven for longer periods of time (a week or so at a minimum) and the judder is getting hideous. It's hard to pull away without the whole car shaking and changing into any gear results in juddering. 4th gear didn't want to engage properly last night & there appeared to a slight slip when changing into 4th (but not other gears).

I'm assuming that there is a small leak somewhere resulting from taking the engine out/gearbox apart to fix the thrust bearing/burst clutch pipe in April last year. Any other ideas or anyway I could try and resolve it without taking the engine out again (other than drive it regulary)?

When I have the money I'm planning on changing the car's clutch/gearbox to accept a 5speed unit (and probably the crank, but thats another day) so don't really want to pay money to fix this thing (plus of course I have none at the moment)

thanks for any advice :)

[GreenV8S]

My guess would be that the clutch is not transmitting torque ymmetrically. Perhaps one or more clutch fingers have failed, or perhaps the lining is just worn out. Either way it sounds like a fundamental mechanical problem inside the bell housing.

[trackcar]

Agree with Peter .. time to get your spanners out again.

Seems maybe a common Marina problem? .. I remember a marina van at a garage i once worked at and the judder on that was very bad.

[gingerprince]

Could also be your diff. My TVR has the same symptoms and is due a diff rebuild.

Have a listen on tickover and see if you have a "rattle" near the diff.

[docevi1]

Thats not good news.

To get to the clutch means a complete engine removal - this was the last time. Might have a word with a garage to see what they can offer in the way of equipment as fighting it with trolley jacks isn't favourable.

thanks for the advice, even if it's not what I wanted to hear

[ARH]

Are you sure it is not the prop shaft, as in my experience they are more likely to fail. Also I remember years ago having a similar problem on a marina this was sorted by rplaceing the clutch slave cylinder, I still can't work out why but it fixed it.

[MOTCO]

This has been a Ford trait, in my experience. Two 2.8i Capris and a Sierra did this and SWMBO's Escort does it too. The remedy, albeit temporary, I find is to give it some really harsh slipping to strip off the glaze that coats the plate and causes this stickiness. Marina clutches, also in my experience, are troublesome, although I know only the 1.3 model. I fitted a new driven plate and release mechanism to my Father-in-law's '72 1.3 Marina and despite its being correctly fitted (what can go wrong if the plate is the right way around?)it consistently failed to disengage fully. A colleague's 1.3 did the same. Obviously a dimensional problem.

[docevi1]

the prop was replaced last July and has been checked since - it doesn't appear to have any play.

the slave cylinder was refurbished in April last year as well, although the Master has never been touched by myself. I have spares so will refurb one and put it on.

I have noticed a couple of things this morning mind,

* firstly where the master cylinder piston attaches to the pedal is badly worn into an oval - this along with a badly worn pivot created a slight slop at the top of the pedal travel. A new pivot has been put in which helps eliminate it, but it'll be better with a new master-cylinder.
* we pushed a lot of hydralic fluid through the system by bleeding it for a long time.
* we topped up the oil in the gearbox, well put a bit in but it didn't flow out so the g/box isn't full.

It appears to have helped. The judder is still there, but nowhere near as violent. Does that suggest anything to anyone?

[ARH]

The pivot between the pedal and master cylinder can be drilled out and a larger pin put in this will remove play, just make sure there is enough metal left round the hole because it will need to take a lot of force. also you will find were on the end of the shaft from the clutch lever to the slave cylinder, this may need to be replaced.

[Mutant Rat]

Just to add to the above, it could also be that it has become contaminated with oil.

When you take separate the engine and box to look at the clutch, check for leaks from the crankshaft oil seal or other sources.

It is unlikely to be the diff., as Gingerprince suggests, unless it is a LSD. LSD's do judder or chatter when worn (and the Gingerprince's Griffith has an LSD) because they effectively have wet clutch plates inside them, but conventional, open diffs just whine or rumble.

Oh...and there's a slim possibility it might be engine or gearbox mounts breaking up, too. I assume your Marlin is a live rear axle, so it couldn't be diff mounts...

>> Edited by Mutant Rat on Monday 29th August 19:51

[GavinPearson]

Your judder may be down to friction plate contamination. It sounds like you also have a clutch reserve issue based on the comments about not being able to select 4th easily.

In this case I would bleed the system - I recommend an Easi-bleed, then check clutch reserve by trying to select 1st gear whilst pushing the clutch down. You should have about 1.5 inch of pedal travel after you have got the car into gear - much less than that and you have either worn components or mismatched hydraulics (not unheard of in a kit car).

Assuming this is OK the judder may be able to resolved temporarily by doing 20 2nd gear starts from rest. Allow 1/2 a mile between them.

One of the key reasons that people get judder after a clutch replacement is overgreasing of the components.

The best advice I give is this - when you are reassembling the gearbox to the engine liberally smear grease all over the input shaft, then using some kitchen paper towel wipe it all off. The surface should be just tacky. Same goes for the pilot bearing, release bearing and pivot.

[GOM]

Agreed; from experience with BL running gear many moons ago it is most likely clutch is contaminated with oil. Had several old minis with the same problem.

[LongQ]

GOM said:

Agreed; from experience with BL running gear many moons ago it is most likely clutch is contaminated with oil. Had several old minis with the same problem.

Somewhere from the dim and distant past I seem to recall a 'fix' for this that involved a can of Coke being poured into the clutch housing. I think the idea was that it would dissolve anything and therefore would remove any contamination on the clutch but leave the friction plate with enough material for further use ...

Is this one to check in snopes?

[GavinPearson]

TBH if it were possible to fix a problem by pouring a gallon of Coca Cola into the bellhousing I would have issued it to numerous dealers as a Technical Service Bulletin.

If you poured brake cleaner in there it would do very little, because the cleaner wouldn't get on to the friction material even with the pedal down, and it couldn't evaporate off. It would also take with it the lubricants in the lining material that stop it grabbing.

You are better off pouring it into a glass and enjoying it rather than trying to fix your car with it.