Trans/Clutch problem diag. Need help.
08-05-2006, 02:29 PM
#1
Trans/Clutch problem diag. Need help. I'm stumped on this one. This is the first time I've had one of these cars apart. I'm a BMW tech, so this setup is a lot different.
The car trys to engage when in neutral, with the clutch out. A grinding noise comes and goes. This car is all stock driveline wise. I blew the stock rear, so now it has an auto rear in it, and a 3.5" LPE driveshaft.
I drove the car from my house to the shop, approx. 5 miles or so. As soon as I put the clutch in, the car drives fine. No noise from the clutch/gearbox as soon as I depress the pedal. The car goes into gear fine, and drives normal, no slipping what-so-ever.
With the car up in the air, in nuetral with the clutch out the rear wheels will turn, but the grinding noise comes and goes. As soon as you can't hear the grinding, there's no movement of the driveline.
I already went ahead and ordered a Spec 3. So I have all the necessary parts to put the car back together.
My initial thoughts were:
-pressure plate had come apart, possibly a finger or two was damaged...
-pilot bearing was junk, and binding up and releasing
-throwout bearing/hydraulics had somehow **** the bed
-Input shaft bearing toast
Everything seems to be fine in those regards. My flywheel and pressure plate surfaces are pretty well toasted though.
There's also a lot of play at the end of the throwout bearing/slave assembly. The bearing itself has about 1/4" of movement in any direction.
The input shaft on the tranny has no play in it in/out. Approx .002/.003 thousandths up and down movement which is normal to me. Everything rotates fine, no binding that I can find.
My buddy can't resurface/balance my clutch assembly until Monday, so I'm on hold.
Thoughts?
Looks like a Gforce T56/Mcleod Twin Disk will be on the way sooner than I thought
Rob
The car trys to engage when in neutral, with the clutch out. A grinding noise comes and goes. This car is all stock driveline wise. I blew the stock rear, so now it has an auto rear in it, and a 3.5" LPE driveshaft.
I drove the car from my house to the shop, approx. 5 miles or so. As soon as I put the clutch in, the car drives fine. No noise from the clutch/gearbox as soon as I depress the pedal. The car goes into gear fine, and drives normal, no slipping what-so-ever.
With the car up in the air, in nuetral with the clutch out the rear wheels will turn, but the grinding noise comes and goes. As soon as you can't hear the grinding, there's no movement of the driveline.
I already went ahead and ordered a Spec 3. So I have all the necessary parts to put the car back together.
My initial thoughts were:
-pressure plate had come apart, possibly a finger or two was damaged...
-pilot bearing was junk, and binding up and releasing
-throwout bearing/hydraulics had somehow **** the bed
-Input shaft bearing toast
Everything seems to be fine in those regards. My flywheel and pressure plate surfaces are pretty well toasted though.
There's also a lot of play at the end of the throwout bearing/slave assembly. The bearing itself has about 1/4" of movement in any direction.
The input shaft on the tranny has no play in it in/out. Approx .002/.003 thousandths up and down movement which is normal to me. Everything rotates fine, no binding that I can find.
My buddy can't resurface/balance my clutch assembly until Monday, so I'm on hold.
Thoughts?
Looks like a Gforce T56/Mcleod Twin Disk will be on the way sooner than I thought
Rob
08-05-2006, 03:26 PM
#2
If your drive wheels are spinning with the clutch pedal depressed and up in the air, your clutch isn't disengaging. That could easily cause your clutch to heat up like a ****, since it is constantly grazing the pressureplate/flywheel. It would be just like slipping the clutch too much, only doing it all the time since it would never stop unless it was fully engaged.
Causes - it could be a hydraulic issue, it could be a clutch issue...hell, it could be one of many things (even pressure plate bolts backing out if you didn't get some good loctite on them). There are so many variables when dealing with this - if the clutch isn't fully disengaging, an adjustable master cylinder or a slave shim to move the slave a little forward could help. Either way, though, you need to make sure you check this and fix it before you put a bunch of miles on it - after you get the clutch in, make sure the wheels don't spin with the clutch pedal to the floor. Otherwise, you'll end up with the same crap.
Causes - it could be a hydraulic issue, it could be a clutch issue...hell, it could be one of many things (even pressure plate bolts backing out if you didn't get some good loctite on them). There are so many variables when dealing with this - if the clutch isn't fully disengaging, an adjustable master cylinder or a slave shim to move the slave a little forward could help. Either way, though, you need to make sure you check this and fix it before you put a bunch of miles on it - after you get the clutch in, make sure the wheels don't spin with the clutch pedal to the floor. Otherwise, you'll end up with the same crap.
08-05-2006, 05:39 PM
#3
With the clutch depressed, the noise goes away. All driveline movement stops as it should.
As soon as I let the clutch out in neutral, the noise comes/driveline tries to engage.
I re-read my post, and can't find where I may have confused you.
As soon as I let the clutch out in neutral, the noise comes/driveline tries to engage.
I re-read my post, and can't find where I may have confused you.
08-07-2006, 09:05 AM
#5
That was in the back of my mind, but I can't find anything to point towards the trans. I'm pretty good at building T5s, but I've never had a T56 apart and I know it's a lot different.
I'm going to re-surface the flywheel, balance the assembly and throw it all together. Everyone is telling me this play in the throwout bearing is normal, IMO it's not. I'll go with the my gut feeling on this one and see where it takes me.
Otherwise it's storage time and I'll wait till I have the coin to build the whole damn car in one shot.
I'm going to re-surface the flywheel, balance the assembly and throw it all together. Everyone is telling me this play in the throwout bearing is normal, IMO it's not. I'll go with the my gut feeling on this one and see where it takes me.
Otherwise it's storage time and I'll wait till I have the coin to build the whole damn car in one shot.
