changed my clutch but it still slips wtf??

[marmite monster 0]

2.0ltr 16v corrado

changed the clutch today with a new pressure plate and bearing re bled the clutch with new fluid but still it slips???

the bell housing had quite alot of gunk in it maybe clutch fluid?? could a failing slave cylinder cause the clutch to slip?

its better than it was before but on the motorway in 5th as you put your foot down the clutch slips and grabs and slips

 

going try a new slave cylinder tomorrow hope it works

[bbewekim 0]

Could be wrong, I was always thought that clutches need time to bed in... So may slip to start with...

[marmite monster 0]

hum yeah i thought that be someone told me that it should feel sweet from the moment it goes in. :(

[davidwort 0]

if the cylinder leaks you could have contaminated the new clutch friction disc with fluid :(

I'd whip the slave out and have a look

[marmite monster 0]

im sure the old one was bone dry when we took it out

 

also when i first went for a test drive round the block after fitting the new clutch it slipped just the same as before we started .

so i re bled the clutch and it was 80% better, i was thinking that i had sorted it until i got on the motor way in 5th put my foot down and the clutch slipped again gutted :( could me bleeding the clutch again have made any difference to how hard the clutch bites i couldnt work out how?

 

am i right in thinking if the clutch slave cylinder was leaking it would leave it stuck in gear as there would not be any pressure in the system to release the clutch?

[Whitedog 0]

am i right in thinking if the clutch slave cylinder was leaking it would leave it stuck in gear as there would not be any pressure in the system to release the clutch?

 

 

Hi Si, that sounds logical but it depends how much its leaking by, if its dropped loads then yeah, no pressure but then you wouldnt get any friction then. If its just a very small amount could still have the pressure but also a bit spreading causing slipping. Worth whipping it out to have a butchers/rule it out.

 

Could it be possible that you may have some air trapped in the system, if it seems to be doing it randomly.....i would try bleeding it again and see.....cant hurt afterall.

[dannyboy 0]

take the slave cylinder out,check the seal.if ok check if oil is leaking from crank seal behind the flywheel or sump gasket.

 

Have you checked the flywheel surface before you put the clutch back on?clutches only work if surface theyre attaching to is flat and not distorted

[Wullie 1]

As the clutch is held to the flywheel by spring pressure and that pressure is released by the slave cylinder then a fault in the slave or the clutch hydraulics would mean that the clutch wouldn't release properly. not cause it to slip. Possible causes could be as mentioned previously, scored or damaged flywheell, contamination with oil/hydraulic fluid or somewhat less likely high spots on the new clutch friction material. These will wear down with use and the clutch will come to you.

 

Only way to be sure though is to pull the gearbox off again and look.

[marmite monster 0]

thanks for all the comments guys :D

well today got a brand new slave cylinder fitted it re bled the system loads of pumping and holding.

still the same .??? :censored: the old slave had no signs of any leak but the little dust boot thing was split.

 

would it be possible that me driving it round for a day maybe 30 miles before i changed the slave cylinder has glazed the clutch in some way?

have noticed that after driving it for a bit the bite gets a bit better than when it is cold i assume this is just the heat making it work better like a brake pad.

 

as for the crank bearing i was told that it was dry but there was al load of oil/cack stuff in the bottom of the bell housing.?? there is no oil leak on the car i put some paper under it last night and it was spotless this morning.

 

dont know what to do next apart from drive it about see if it gets any better. :(

 

anyone got any other ideas really don't want to take the box off again if i have to

[Majik 0]

Where did you buy the clutch from? What brand?

I've come across some clutches that judder even though they were brand new and some release bearing that were noisy, (mainly from ECP & GSF)

As mentioned before the surface of the flywheel is an important factor perhaps engine oil is dripping onto the flywheel.

[marmite monster 0]

got the clutch from my local auto spares place i have a trade account and they only get good stuff . i rang and asked them if they had ever had any of these clutches returned and they said in 5 years of selling that brand (cant remember which one) only one and that was because it was the wrong clutch in the box. so im kind of ruling out the clutch as faulty but i suppose there is a chance it may be ?

 

it has to be some kind of oil on the friction plate

[pete_griff 0]

it does sound like the friction plate is being contaminated somehow...

 

could oil and/or clutch fluid be getting into the bellhousing?

 

it's crap, but now you cleaned it up a bit, it would probably be best to get it all off again and have another look...

[marmite monster 0]

Ive come to the conclusion the National clutch is faulty so its coming out and im going to put a LUK one in. :( :( :pukeright: :(

serves me right for buying a £69 clutch.

[RW1 0]

Ive come to the conclusion the National clutch is faulty so its coming out and im going to put a LUK one in.

LUK from experience ain't good after a while, use original VW if you can afford.

 

Much better engagement.

 

C.

[davidwort 0]

LUK are original equipment, my 8v clutch has just come out and had LUK/VW logos and part numbers stamped next to each other, it was the original factiry clutch no doubt.

I've had two sachs ones from GSF and ECP and they are fine, they do a 230mm clutch now that is a replacement for all the 4cylinder 228mm clutches (they are actually 228mm if you measure them though), spot on as far as I'm concerned, 60 quid with trade discount from ECP.

[RW1 0]

LUK are original equipment, my 8v clutch has just come out and had LUK/VW logos and part numbers stamped next to each other, it was the original factiry clutch no doubt.

 

That's unusual as they have been FUS (Sach) for as long as I can remember. But... you learn something new every day...

 

But given they fitted alternative French distributors to Mk2 Sciroccos when they had a Bosch shortage in the late '80s, I put nothing past VW doing anything to keep production going.

 

Still wouldn't fit LUK by choice for me though, two clutches of theirs in the recent past and no way, not again. I expect 70k miles out of a clutch for me and they both came out at 20k miles with my left leg aching due to the increased force required as well as the lack of a progressive engagement disappearing over time. When out, both appeared only lightly used, so no explanation for the change of character of operation. Trade I know are of the same view.

 

.

[davidwort 0]

viewtopic.php?f=11&t=19344&start=90#p1125355

my 8v LUK next to the new sachs one, LUK one did 160K on the 8v, never fitted a replacement LUK I don't think myself, but speaking to my dad (still works at a garage) they fit LUK ones to all sorts of cars and seem to regard them as a better quality clutch than the real cheapo ones :shrug:

[Toad 0]

Did you properly degrease the pressure plate? And made sure the flywheel was clean before refitting? All the pressure plate to clywheel bolts were torqued up? How about the release arm? was that straight and fitted correctly?

[marmite monster 0]

sorry guys forgot to update this thread . anyway after trying everything possible to get this clutch to work in the end i had midland vw take it out the old/brand new.this clutch was bone dry and had been fitted perfectly,but you could see on the friction plate were it had been slipping as it was badly glazed. they fitted another new clutch this time LUK and it worked fine! :cuckoo:

sent the old clutch back and got a full refund. im still waiting for the engineers report from them to say what was wrong with it im guessing the pressure plate springs were faulty maybe.

anyway all fixed now :D

[Supercharged 2]

That's the second faulty LUK clutch I've heard about in as many weeks...

[davidwort 0]

That's the second faulty LUK clutch I've heard about in as many weeks...

no Steve, he took another cheap brand one out (the original replacement) and replaced it with an LUK one to fix the problem :)