BXProject

[docchevron132]

Kates birthday today, well, yesterday now..
So, I took her and the puppies for a stroll round Chrterhouse near Cheddar.
Lovely place it is..
Anyway, drive down, no problem..
On the way back on the A37 it gets a bit up hill for long stretches, bit of downhill, then more uphill and so on.. the joys of the Mendips and all that shit like..
Anyhow, I'm going up a fairly steep slope at 40MPH in third, then open the throttle to overtak a very slow moving camper, and I get enormous clutch slip.
Ok, at those revs the turbo's blowing 1.2 bar, so not quite full boost, but not far from it.
I back off the gas until it bites, and I give some welly again. Same thing.
Drop it into second and floor it, no slip, goes off like a scalded cat, overtake the camper, pull in, change up to third, open the pedal, slips like a cow with bad burning smell..
So, I go playing a bit, much higher road speeds in fourth and fifth, pedal on the floor, no slip.
So I try lower speeds in first and second. No slip, just lights the tyres up.
Fuck thinks I, the clutch is goosed..

Bear in mind, I dont ever wear clutches out. The three clutches I've put in this car over the years (albeit with NA engine until recently) failed through the release bearing wearing through the pressure plate, the friction plate always had plenty left on it.
I dont do "chav" standing starts, and never have, I dont slip the clutch at all really, just let the pedal up at idle and open the throttle once the pedal is released, even for hill starts.
This clutch has done only 38K miles which is fuck all compared to the 250K miles I usually get before the pressure plate fingers fail...
It has been fine up until today, I've never had to adjust it, and the bite point has never changed.

Anyhow, after I got back to Kates we go in and watch telly for a bit, have a bite to eat and all that shit, then some 6 hours later I get in the car to come home.
Drives fine, and I'm trying my damndest to get it to slip, but it wont.
I get all the way home (right across town) and all is well until I stop outside my house and stuff it in reverse to back it on to the drive.
It wont move!
The pedal feels fine, and it goes forwards no problem, but it will not go backwards, all I get is a friction material burning smell..
So I drive off down the road, swing it round and fuck off up the main road at full throttle, all is fine, no slip, no smell, nothing.
Get back home again, reverses onto the drive no problem..
WTF is that all about then?!

[mickey taker]

could an oil seal have gone causing contamination then by booting it it "wipes " it off?

[Philhod]

I think that's where I was going Mickey, as I was reading. However I think it's coming from the g/box rather than the crank seal.
I had a similar thing happen years ago ended up with the clutch plate sticking together and wouldn't release. When I got it out it was leaking from both sides and the oil had congealed on the plate with the heat.
Can't explain the good then no good spots though, unless there are bits coming off the plate getting trapped and then clearing.

[jayw]

Is it possible the clutch release arm bush is worn causing the arm to stick occasionally? Or the bearing has slipped off the arm fingers causing the same, my bearing came off the arm causing the bearing to be pressed hard on only one side and wearing the fuck out of it.

[David]

Is it possible the clutch release arm bush is worn causing the arm to stick occasionally? Or the bearing has slipped off the arm fingers causing the same,

This is where my thoughts are. It sounds like a release issue rather than an actual clutch issue.

That said, I would expect you to be able to feel the difference in the pedal.

Only other odd clutch experience I've had like this was when 3 of the 6 cushion springs fell out and got jammed in various bits of the mechanism. Caused all manner of wierd effects.

[Vanny]

are thrid and reverse on the same shaft? And is this a clue? or am i barking?

[docchevron132]

nope, third and reverse are seperate..
Pedal feels fine, release arm is all nice and free, top and bottom bush where they should be as far as I can see.
No odd noises from the clutch itself, no difference in weight to the pedal, or pedal height, or operation..
Drove fine this morning until it got up to temp, then exactley the same thing, slip in third, but only third, and I REALLY abused it in every gear, but it's only prevalant in third.
That said reversing has been no issue at all today.
I'll pull the box off and have a look see. At this point I'm still a bit baffled..

[smiffy]

Well you said you were thinking of putting annother engine in it, this might be the excuse you needed...

[jayw]

Having never stripped the gearbox THAT much, is is possible for the 3rd gear to be slipping on tha shaft? i.e (assuming the gears are located on the shaft by teeth) can the teeth be stripped?

[David]

Now there's a possibility I hadn't consedered. That said, I doubt it would feel like slipping.. More like nasty mechanical noises and loss of all drive.

Chris.

From Stationary, can you stall the engine in 3rd gear as easily as you can in say 4th? And/Or does it pull away with normal clutch feel compared to 2nd or 4th?

[docchevron132]

I had considered that third could be stripped, but there is no mechanical noise that would suggest so.

Yep, the engine will stall in every gear exactley the same, even if I put A LOT of revs on it'll still stop before the pedal is to the top of the travel.
I've had a look as best I can down the bell housing, and taken the bottom plate off, cant see anything floating around in it.

It's more not knowing WTF is going on that concerns me, if I knew the clutch was dying then I'd just take it easy until I throw another one in, but I'm always worried that I'm going to get halfway somewhere and it's just going to stop altogether..
If it wasn't such a massive ballache to get the valver out I'd be using that!
Still, I'll hoof another box and clutch in this week, maybe a flywheel too, just for good measure..

[David]

Still, I'll hoof another box and clutch in this week, maybe a flywheel too, just for good measure..

Silly question I'm sure, but do you have plenty of turbo-spec gearboxes? I've about three BE3/5 from turbo cars here, you're welcome to one if you need it.

You'd also be welcome to come and make best use of the 2-post vehicle lift, engine crane and gearbox stand that we have in at my "work". I imagine it would make a gearbox change very easy indeed....

[Philhod]

Still, I'll hoof another box and clutch in this week, maybe a flywheel too, just for good measure..

Which w/end will that be then if yer up in Wales ???

I think he'll have to take you up on that lift David.

[Bx Bandit]

Not the foggiest mate, surely if it's gearing/mechanical ther'd be some major bumping and grinding going on?????

And if it's clutch then 1st and 2nd would exhibit more exaggerated symptoms, as would reverse....

Fuck, just miss out 3rd and problem solved!

[docchevron132]

It's behaving at the mo, although I've not been booting it, but I think I've sussed it.
It's more to do with road speed than gear. Noticed a HP spray of diesel from number 1 pipe.
Replaced the pipe, but I reckon the airflow at certain speeds was moving the jet back enough to enter the bell housing and contaminate the clutch.
I think.
Thre's a small puddle of DERV right next to the vent in the top of the box, whilst stationary the mist was spraying forward of the box, a blow into the mist moved it back to the box.
Either way, it'll want a clutch at least I think now..