Slipping clutch

[jb86]

Friend has 85 turbo diesel jetta
Clutch was slipping in february
We replaced the clutch
Pressure plate
All oem Sachs for the car
Flywheel machined
New rear main seal
Steel pcs washed with alcohol as being assembled
Oem new bolts pressure plate and flywheel
All torqued as Bentley specs
Red thread locker on flywheel bolts
Torqued to 15 lb ft as specd
Tranny was pressure washed
New seals on tranny - input shaft and push rod shaft
New throw out bearing
Everything was clean and assembled with light white lithium grease
New cable - manual adjust, lots of free play
After 2k it's now slipping on the highway
Is it possible that something is hanging up in the pressure plate or the pushrod?
Jon

[Trips_B]

Define "lots" of free play.  Iirc the gap at the throttle cable 2 carrier gromet on the granny is 12mm.  I actually set mine to 8 or so

Did you replace the "finger" when you did the TO bearing if it has a crack in it that could be the problem

[CRSMP5]

did they machine BOTH areas of the flywheel?? not only the clutch surface gotta machine the area that touches the pressure plate.. else gap too big

cracked finger = no clutch release...

[jb86]

He did not machine both surfaces
Only the mating surface
Maybe that comes too close to the flywheel now?
Finger looked good
Jon

[Trips_B]

cracked finger = no clutch release...

you are correct, not too sure what my thought process there 

[billybobf]

probably the lack of proper machining on the flywheel?

over in the toyota world, we actually have them machine the portion that touches the pressure plate more then the surface that touches the disc to get a tighter grip.

[R.O.R-2.0]

probably the lack of proper machining on the flywheel?

over in the toyota world, we actually have them machine the portion that touches the pressure plate more then the surface that touches the disc to get a tighter grip.

because toyota pressure plates will lose pressure when theres still quite a few miles of friction material left on the clutch..

once, my dads friend had a toyota pickup, and we were all over hunting, 600 miles from home, and his clutch started slipping BAD.. so we dropped the trans, pulled the pressure plate, and took a GRINDER to the mating surfaces of the pressure plate, basically making the actual plate sit closer to the flywheel, so it would have some pressure left to grab the clutch disk again..

anyways, we ground down the 3 flat surfaces where it bolts up to the flywheel (removed about half of the thickness of the material) then put it back together with all the old parts, and IT WORKED for the time being. got us around for those 2 weeks we were there, and made it back home also..

but yes, i too, have the mating surfaces machined more than the actual flywheel friction surface.. actually makes the pressure plate bite the disk harder..

[jb86]

I understand
I mocked it up with a flywheel and old pressure plate
With no disk there's maybe a light 1/4" gap between them
The disk is about 5/16"
I saw where they mate
We'll watch it and if it needs it we'll pull it next week
Thanks for the replies
Jon

[Swartzvw]

Also you can use a 16v pressure plate for a little more clamping force.

[Turbofan]

It's possible they incorrectly machined the step on the flywheel too. I just replaced my clutch twice this week (first because I had a bad disc, then I replaced the fancy high clamping race clutch with a stock one because burning out whenever I pulled away from a stop got old) and the machinist was surprised at how many steps there were for MK2's. He told me had I not told him the year it was from, he wouldn't know what step to put on it. With that said, I think all the Jettas and Golfs (diesel) had the same step, so as long as they stepped it to a diesel, and not an 8v gasser, you should be in good shape. If you pull it apart, you could measure the step yourself with calipers, then compare it to what it should be. Just a thought.

[jb86]

I know of a local mechanic (for 50 yrs) that just seems to know a lot about everything
I stopped in to see him
In the way, on the highway the clutch slipped in 5th 4 times on a hill in a 10 mile drive
The last time was on flat highway coming from 4th to 5th
He looked everything over
All looks good
Started it
In 2nd at a stop slipped the clutch while revving
Didn't say anything but I just heard him revving and slipping the clutch
when smoke started coming out of the clutch
He said it should, I'm burning it
He drove it around his backyard a bit
Said - I think you're all set now
It was slipping in 2nd when he first got in
After "working it" it didn't slip
That's been a few days
Hasn't slipped since
He thought maybe something was hung up or got in there
Darned if I know
I figured we had nothing to loose
So far so good
Thanks for responses to try to narrow things down
Jon

[8v-of-fury]

Interesting.. so you msut have had some kind of petroleum product on your clutch disk.. ?

[jb86]

I replaced the rear main seal
Cleaned everything with alcohol
I used a 2 pc bell housing cover plate - it has the remove able cover at the bottom
That way I could see if oil was leaking
Its all dry
I'll just see what happens
So far so good
Jon

[billybobf]

that or maybe just a slick surface on the new disc?

[bbob203]

if you think something got on the disc you could always try soaking it in brake keen a couple times and let dry I've heard of that curing the problem before.