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S2 Gear Shifting Problem?
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Author:  flt505 [ Thu Jan 07, 2016 9:07 pm ]
Post subject:  S2 Gear Shifting Problem?

Hi Folks -

My problem is a buddy that has an S2 Cab that when his car is at a working temperature, the gearbox is reluctant to shift into most gears (grating) whilst driving at normal speed. When 'cold' shifting is fine.

There seems no leaks from the hydraulics and I have checked the clutch tolerance at 26mm - well within the normal tolerance level of wear. However, you can get any gear you want at the right revs...

My previous current posts are about gearbox oil change, of which I am doing one of his, not yet done but could this be the problem or possibly a major gearbox problem?

I am thinking clutch release bearing...?

Dave
SA

Author:  zcacogp [ Thu Jan 07, 2016 10:05 pm ]
Post subject:  Re: S2 Gear Shifting Problem?

Dave,

Change the gearbox oil and see if that helps. Report back if it doesn't.


Oli.

Author:  flt505 [ Mon Jan 11, 2016 9:14 pm ]
Post subject:  Re: S2 Gear Shifting Problem?

Hi Oli and Folks -

Well, I changed the gearbox oil and the subsequent very short road test showed the problem is still there. Whilst driving, even when it is in a gear, it is reluctant to disengage itself back into neutral (clutch depressed) - ie it's jammed in gear. A slight rev and it will then disengage.

Keeping the revs constant, the gears work fine, up and down the gear changes - the problem arises when the revs are not.

I am then surmising (?) that the gearbox is not the problem ie syncros but the clutch release mechanism:

1. That the rubber part of the clutch disc has fragmented
2. That the clutch release sprocket/pin is seized
3. That the release bearing itself is knackered
4. That the master or slave seals are busted (no sign of leakage apparent however)

I am erring on item 2. This car sits around a lot and perhaps the two bearings and the associated pin have become seized or seizing...

Thanks for your thoughts...

Dave
CT

Author:  zcacogp [ Wed Jan 13, 2016 7:37 pm ]
Post subject:  Re: S2 Gear Shifting Problem?

Dave,

I'm guessing here, but ...

- You can look into the clutch inspection port to see how much meat is left on the clutch. Clarks garage has details on this but I think you've already done this.
- If the rubber centre of the clutch is hoopajooped then you will probably see crumbs of rubber in this inspection port.
- If the master or slave cylinder is leaking then you won't be able to release the clutch at all (and the pedal will probably sink to the floor, or not spring back once pressed)

You therefore have the clutch release bearing or the "clutch release socket/pin" (by which I assume you mean the release arm lever and needle roller bearing.)

The clutch release bearing would cause a big noise to be heard when the clutch pedal was pressed if it was worn, but it would need to be VERY worn to prevent the car from changing gear. I'd therefore doubt this.

I guess it's possible that the clutch movement is made sticky by worn needle roller bearings or a damaged lever but you could test for this easily by watching it's movement with someone in the car operating it. Look into the inspection port and see whether things move as they should (although the distance moved will be tiny.)

So, I'd doubtful that any of those options are it. It could be some kind of clutch drag (clutch plate jamming on the spline shaft) or possibly some kind of synchromesh wear in the gearbox. I'm not aware of any setting or alignment that could be wrong in the mechanism but it would be worth making sure that the gearshift is indeed working as it should - i.e. that the pin on the bottom of the gearstick isn't stupidly worn and that the mechanism on top of the gearbox (a pain to get to) isn't jamming on something. Either of these latter two options would be a simple explanation.

Let us know how you get on.


Oli.

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