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Discussion Starter · #1 ·
I've got a strange problem that just doesn't make sense...so, any thoughts on this one:

The problem is that what started out as a "clutch needs
bleeding" diagnosis on my part has not been the case.

Even after bleeding the clutch doesn't come back up properly on releasing (can be popped up by foot) - although drive is engaged OK. Pressing accelerator (henceforth known as gas for ease of writing) makes clutch pedal pop up.
See-Saw action detected - applying slight pressure to clutch pedal and
then on and off gas causes clutch to go down (no real back pressure, it
just drops) when lifting off gas, but clutch presses back up on
applying gas.
The above behaviour is detected in gear 1/2/3/5 and R, but not 4th!!
Example :
Go from 2nd to 3rd:
Lift off gas / Clutch goes down a bit (as above) when slight pressure
applied, push all the way down, and clutch engages, change to 3rd,
release clutch (pedal doesn't return up), apply gas, pedal pops up.

Go from 3rd to 4th
EXACTLY the same, but on applying gas, clutch does not pop up. I can
come on and off gas in 4th, and clutch pedal remains stuck down (about
1 inch off floor).

now - two interesting points from this stage:
1) If I pop up clutch pedal with foot, and then press down again, there
is really GOOD pressure. Nice weight, engages well etc
2) Remember I said I can come on and off gas in 4th and pedal remains
down. If I leave pedal alone, don't touch clutch at all, and slide in
to 5th (let the synchromesh do the work), as soon as apply gas, pedal
pops up. I suspect if i did the same down to 3rd (with a blip of gas
in neutral to help), it would do the same.

So - points of note;
- My reference to "pop up" is the fact that the pedal is counter sprung
- so it compresses the spring on down and up, hence the "pop" is caused
by the pedal spring holding the pedal down, and then pulling back up
past the mid point. My analysis though is that when the pedal sticks
down, there must be no return pressure from the hydraulic system/cluch.
- I HAVE bled the system completely. It just doesn't feel like a
hydraulic problem now...If it was master cyl., then why is it PERFECT
in 4th (good back pressure), and PERFECT when stationary with no engine
running.
- If it were the slave, same applies really.

- Since it affected by on/off gas, it sounds "torsional". I have
checked engine mounts/gearbox mounts. they are fine (the car is a 52
plate, 110k miles). There is absolutely no drivechain noise (clonks
etc) when coming hard on and off gas in, say 2nd.
- There is no release bearing noise

So, I'm guessing this must be something going on in the bellhousing
(still don't quite understand how the gear can affect this), but since
there are no pics in the Haynes guide of the bell housing, and the
clutch release assy is all contained within it, with no inspection
point, I need some idea of what this could be, or why.

I'm more than happy to pop the gearbox out, but would ike to be armed
with either clutch kit or release cyclinder assy, and not both, before I do it.

Any thoughts would be useful. I really think I've covered everything
I'm a more than competent DIY mechanic and have replaced countless clutches on RWD cars.....I think I've seen a good number release mechanisms, cable and hydraulic......but this fault is stumping me. I guess it could just end up being cover plate springs......but why the 4th gear anonmoly!!
.......and why would a 3.5 year old car, with 110k have a shot
clutch......to do that mileage, generally requires lots of long trips
(and I know it was an Exec's car, doing travelling all over the
midlands), so it's probably done less gear changes than Mrs Housewifes
Corsa with 12k on it.

What's the score with a dual-mass flywheel - don't these beasts have
one? could this be a factor?

Help!!!

Rich
 

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Sounds like a problem with the pedal box? Tried greasing the pedal pivots? Checked the sping in the pedal? Has it snapped? Maybe you dont know you own strength and have bent the bar the pedals pivot on :smile
 

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Discussion Starter · #3 ·
Sounds like a problem with the pedal box? Tried greasing the pedal pivots? Checked the sping in the pedal? Has it snapped? Maybe you dont know you own strength and have bent the bar the pedals pivot on :smile
Checked that first - spring fine. Pivot solid
 

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. . . . What's the score with a dual-mass flywheel - don't these beasts have one? could this be a factor?
Help!!!
Rich
The dual mass flywheel is a strange beast. One connects to the crankshaft (conventional) and the second is sprung from it. The clutch disk doesn't have any springs.

When I had problems I was told (on here somewhere) that as long as it wasn't causing a vibration it was probably OK. I didn't do anything to it just changed the disk and pressure plate.

My clutch went into a mode where it wouldn't disengage. Then, after about 20 miles I got no drive at all. Turned out that the disk material had broken up on the pressure plate side and jammed but then after a few appications it all fell off. Yours doesn't sound that drastic.

Mine had only done 64,000miles but it does get used for towing. It was originally registered to a main dealer and was sold as a Director's car but I suspect it was really a hire car so I have no idea how it was treated for the first 18000 of its life.

 
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