As the title says, when I press the clutch pedal in, the revs jump up to around 1500 revs and sit there for several seconds before subsiding. They never did this before tonight so was wondering if there's something amiss, or if it's just one of those things.

Also, still on the subject of the clutch, when the engine is cold, I here a light scraping/grinding noise coming from the clutch when I put pressure on the pedal, it doesn't have to engage/disengage the clutch, just a small amount of weight on the clutch pedal starts this noise off...any idea anyone?

I would be checking that the throttle peddle is returning all the way back up quickly and smoothly. Maybe yours is jamming a bit at the top, or the spring that pulls it back up has become weak making it rev too long? Good luck

check the throttle cable at the pump end, mine did the same and the cable was sticking and causing the plastic adjuster bit to move out of the hole and jam the throttle open. the clutch noise i would suspect the release bearing is on its way out.

Shirley Throttle Body end? It's a 3.9 V8.

Some years ago I read of someone's experience where the cable somehow came out the slotted hole & the knurled plastic adjuster jammed & kept the revs dangerously up & uncontrollable .



Since then, I have had a cable tie around that cable & adjuster to ensure it will not come out. Belt & braces stuff for me.

Could do with a little more detail here.. This is probably caused by the air bypass valve raising the revs under instruction from the ECU - the problem is why is it doing this?.. This is where more detail would be useful:

• Does it only happen when changing gear?
• Does it only happen in neutral when stationary?
• Does it only happen when on the move?

You get the idea!

Rog

ha sorry didnt realise it was v8. yeah throttle body end. i may add a cable tie to mine...

This morning on the school run it was behaving itself, but last night, it was doing it on every gear change, whenever I slowed down, I'm not 100% if it did it when in neutral..can't recall, but if I lifted the clucth peddle to biting point, it would drop again.

this only became apparent toward the end of my journey home, so the engine would have been at operating temp.

well, just had a run out in it..and it's behaving now..except the grinding noise.

I've decided that as it's clutch related, and it's got over 120k on the clock, and in all likelyhood the original clucth, I'm just going to have the clutch replaced....unfortunatly it may put pay to the megasquirt conversion I had planned and had the money saved for, but I reckon changing gears is a little more important then driving through water.

This sounds to me like the air bypass valve is sticking - this is at the rear of the plenum chamber with wires leading into it. If you remove it and clean it with brake cleaner and a toothbrush you will probably get a while out of it before it needs doing again. If it does need replacing then they are expensive - £55 plus vat & del from Paddocks but try cleaning it first - in my experience it usually works and only takes ten minutes.

Rog

And if you don't have a working clutch, you won't be driving through anything, water or not.

Thanks, I'll give it a clean tomorrow...I've done that in the past aswell, but no harm in another clean

Anyone know how long it takes to change a clutch? I've been told by the garage they need the car for 2 days I know it's a big job, but when I've changed clutches before, it was nothing like that long, just a few hours

I've never done one, but from what I gather there is a hell of a lot more labour involved in changing a Discovery clutch as compared to the usual 2wd eurobox.

TC may have to come off etc etc
Make sure they inspect/ reinforce/replace the clutch fork arm for wear. Do as much as required & more, while they are in there.

Re the stepper valve:

I found that once mine started to go I would clean it but it would only be a few weeks until it needed cleaning again. Eventually, over a few thousand miles, it got so I would be cleaning it every couple of days. I was commuting in it at the time and it got so bad that I eventually replaced the valve and - no more problems since then. (Well not yet anyway... Well not with the valve anyway...)

Rog

Bloke who did my last Discovery clutch takes 4 hours. I must admit he does fit them all the time (does a lot of work for Ashcrofts). So I can't see why they would need it for 2 days.

HTH

Ivan