Slipping Clutch

Smiley · 2010-06-21T10:20:37+00:00

I've been having dramas with a slipping clutch in my Baja. The story goes like this. Started slipping while I was down in Brisbane for TAFE. That was fine, the clutch was very old and I guess it was well past it. So I put a new clutch plate,a good second hand pressure plate, a new throw out arm and a new throw out bearing in the day before I left to come home. On my way over the gateway the next day the clutch started slipping. Did this the whole way home, which made overtaking a PITA because every overtaking lane seemed to be on the uphill stretches. That's ok. Must be the flywheel that's the problem. I took the flywheel out of my dad's deregistered Baja, it was recently machined about a month before we took it off the road. Was fine for a day or two but working her hard at 100kph in forth up a hill coming out of Rocky the clutch started slipping again. I figured I might have an oil leak. Pulled the engine again, installed a new rear main (wasn't actually leaking). Cleaned everything up again and put it all back together again. But on the way home from work today the bastard started slipping again!!!😬 So to recap I have a new clutch plate (over 8mm thick), new pressure plate, machined flywheel and a new throwout bearing. Everytime I've done it the clutch has been adjusted correctly and is not riding on the throwout bearing. Can people please tell me what the hell is going on cause at this stage I'm completely stumped. Also, does anyone know what the depth measurement for the flywheel should be between the face where the clutch runs and the face where the pressure plate bolts on. Cheers in advance. Smiley 😎

bajachris88 The international telephone dialing code for Antarctica is 6

6,661 posts · joined Apr 2005 · 26 Jun 2010, 12:43 pm

#786984

OY!

Daniel, just thought, if u have a dirty amount of crankshaft END FLOAT, that will cause clutch issues. particularly up hills (crank slides back), or if u power on (crank gets thrown back).

Its one thing you haven't checked yet!!

http://www.vw-resource.com/endplay.html

(ô_!_/ô) (ô_!_/ô)
69' baja: kombi box, thing spindles, irs, disc front, type 3 rear drums, 2 inch lift kit, 31x10 rears. 👍
New engine in process: 94mm p&bs, 74mm C/w chomol Crank, 35.5x39 SP heads, turbo. Wierd combo, hopeful torque monsta!

Smiley Veteran Volks Folk

2,125 posts · joined Oct 2008 · 26 Jun 2010, 2:22 pm

#787002

bajachris88 wrote:Hey Daniel, when you got the flywheel machined, was it machined to perfect mirror finish?

The usual mechanics shop make it almost like that, but rather than a smooth surface like what a 'well used' flywheel surface looks like, they have a very fine gritty swirl texture the whole way around, gritty enough that if you press the clutch plate into the flywheel with ur hands, u won't be able to slip it around. A mirror finish will slip if u press the clutch disck into it with ur hand (vw flywheel did).

Like... its got to be evenly rough enough to 'grab', but no where near mirror finish so it doesn't slip and of course, doesn't eat ur clutch plate much. I would send a photo of mine done at my mates mechanic shop (sent up the road), but i just fitted it and assembled the box back on my ricer.

the machine job should be rough enough to see concentric fine circles all the way around, and rough enough to slide ur finger nail across and feel a 'very' slight roughness. and still be fine enough of a machining job to see a shine to it but not necessarily see ur own reflection lol.

again, maybe the flywheel hasn't got enough meet, and its too old/ been too machined. 🙁

I am suspecting this Chris.
When it was done at work it was done with a lathe and tool steel, so to a mirror finish.

I'm going to dig around my bits and see if I can find a 200mm flywheel and a starter to suit then have it ground properly and buy a new clutch kit.

Greedy, when I pulled the flywheel it's the type with no O-ring so I didn't replace it. Just the lip seal.

Smiley 😎

If you said I was a Volkswagen man, you'd be right.

Smiley Veteran Volks Folk

2,125 posts · joined Oct 2008 · 27 Jun 2010, 6:22 pm

#787277

I was just out in the carport and saw the old flywheel out of the Baja sitting there. I grabbed the verniers and measured the depth.

24mm!!!

No wonder it was slipping.

I'll have to check the one that's presently in the car too and see if there's any variation from spec.

Smiley 😎

If you said I was a Volkswagen man, you'd be right.

matberry Moderator Go hard or go home

8,114 posts · joined Mar 2006 · 27 Jun 2010, 9:53 pm

#787327

Smiley wrote:24mm!!!

Smiley 😎

Bingo

Matt Berry Motorsports...air cooled advice, repairs and mods Ph 0408 704 662
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE

bajachris88 The international telephone dialing code for Antarctica is 6

6,661 posts · joined Apr 2005 · 28 Jun 2010, 12:19 am

#787369

Sorry if its been said... whats the minimum thickness spec? take it thats the thickness of the flesh on the flywheel from the friction surface to the other side? (nuffin like a stupid question hey? cough cough 🙂 )

(ô_!_/ô) (ô_!_/ô)
69' baja: kombi box, thing spindles, irs, disc front, type 3 rear drums, 2 inch lift kit, 31x10 rears. 👍
New engine in process: 94mm p&bs, 74mm C/w chomol Crank, 35.5x39 SP heads, turbo. Wierd combo, hopeful torque monsta!

Smiley Veteran Volks Folk

2,125 posts · joined Oct 2008 · 28 Jun 2010, 9:39 am

#787384

bajachris88 wrote:Sorry if its been said... whats the minimum thickness spec? take it thats the thickness of the flesh on the flywheel from the friction surface to the other side? (nuffin like a stupid question hey? cough cough 🙂 )

It's the distance from the surface where the pressure plate bolts on to the surface where the friction material of the clutch plate bears.

Matt posted somewhere earlier that it should be 21mm.

Thanks Matt by the way.

Smiley 😎

If you said I was a Volkswagen man, you'd be right.