y8s

iTrader: (8)

my clutch hydraulic system has had at least a gallon run through it in the last 6 months. I trust it to be bled.

do pilot bearings stick? I checked it when it was out last and it was smooth.

patsmx5

iTrader: (16)

There's no way in hell it's the pilot bearing. That things tiny, just imagine how much torque it would take going through that little 1" bearing to actually spin all the gears in the transmission full of oil, the driveshaft, and the diff full of oil. That bearing just makes a lot of noise when they go out, it won't cause what your describing.

Your clutch disk is rubbing the flywheel or PP. In your case, you have a fancy twin disk setup so whatever the disk touch, they are touching! Your supposed to use some high temp grease on the input shaft so the disk will slide smoothly. Did you? Obviously you have two disk so there's more friction, causing your problems.

FWIW, I let a shop put Centerforce dual friction clutch in my 86' Trooper II (3" lift on 33x12.50's 10 lights, wench, brush guard, Weber conversion, cold A/C, 70 hp...) and they didn't grease the input shaft AT ALL. So my transmission does the same thing your describing. If I pop the clutch out quickly, it will sometimes get the disk off the flywheel. Needs to be taken off and the splines greased. I actually cleaned them with a wire brush and brake parts cleaner so it would be clean when assembled, but the dumbasses didn't grease the shaft, or tighten any bolts, etc.

y8s

iTrader: (8)

I can take it apart when I swap motors (some day)

so tell me ... this hasn't been directly answered yet: why is it fine and then after say 30 seconds at a stop light does SOMETHING happen and I feel the clutch start to rub randomly?

patsmx5

iTrader: (16)

You tell me... Did you grease the input shaft of the transmission with high temp grease before installing your disk?

y8s

iTrader: (8)

far as I know. I used the same **** I used the first time I put the twins in--they worked fine before.

ZX-Tex

iTrader: (15)

Seems to me that could be caused by a leaky master or slave piston cylinder. It disengages at first, then slowly re-engages? The piston could be moving slowly due to a leak.

y8s

iTrader: (8)

indeed it makes sense. then the effect reverses, the clutch re-dis-engages and the wheels are free again.

gremlins!

ZX-Tex

iTrader: (15)

I think you have a loose nut between the steering wheel and the driver's seat
Weirdness...

patsmx5

iTrader: (16)

Try this.

Hell, I dunno. I would assume your master cylinder and slave cylinders are in good shape, properly bled, no air, you bench bled the master cylinder, etc. If all that's good, and pedal adjustment doesn't fix it either, it's time to pull the transmission. I remember you had to extend the rod on the slave cylinder I think? Perhaps the geometry in that area is wrong and the reason you're not getting full disengagement. This is my hypothesis. I assume the clutch assembly wasn't sticking out enough for proper disengagement, so you extended the rod on the slave. Ideally you would have moved the fulcrum and kept the geometry correct and your slave stock. Any way to do that? Sorry, never had my transmission off (yet).

Braineack

iTrader: (62)

you realise he has a custom dual disc tilton setup?

patsmx5

iTrader: (16)

Si. Note I made reference to the custom slave cylinder, and how his clutch assembly didn't stick out as much as normal.

y8s

iTrader: (8)

ok so my geometry is preserved. I lengthened the slave rod and shortened the fork pivot to keep the fork at the same angle.

it could be a mild warpage issue--when the disk is cold maybe it rubs and as it rubs it warms up and becomes flat again. lather rinse repeat.

but I doubt it because stone cold the car is not consistently problematic. so who knows. perhaps I hang out with scott too much?

chpmnsws6

iTrader: (12)

If it is actually pulling you forward, then you have a leak in the master or slave. Have you checked the external condition of either? The slave cannot have an internal leak, so everything for the slave would be "outside the box". The master cylinder can have both an internal and/or external leak. Again, you can see the external leak when you pull the dust boot off, but with an internal leak it is bypassing the seal and going back to the reservoir, feeling like the clutch is being released.

Another question- Why are you holding the clutch for 30 seconds at a time? Not only is that running your clutch release bearing, but it also could be killing your thrust bearing (or bearings, don't know, have not cracked open a mazda engine).

chpmnsws6

iTrader: (12)

Also on a side note, if you have a dual disc, they normally rattle around with the clutch disengaged? I couldn't stand to have my dual disc rattling at intersections..... made the car sound like a POS between the cam lope and the rattle.

y8s

iTrader: (8)

OH it rattles... but it's not that bad.

Not worried about thrust / release bearings. after 80,000 miles, they seem fine.