Hladun1

Replaced the clutch on my78SC because of clutch spin/drag problems. Transmission shifts very easily now with no reverse gear crunch. Process went quite well, and here are some things I learned.

First, two floor jacks; one under the engine and one under the transmission mounts make removing the engine and transmission assembly very easy. You can hold up the trans as you lower the engine and not damage the shift rod. You can also use the second jack under the transmission when you separate it from the engine. I recommend taking engine/transmission out together.

My pressure plate spring had cracked and this caused the clutch spin/drag. It made shifting into first and second hard and reverse grind. I had posted a clutch drag question previously but only got “usual suspect” answers to adjust the clutch cable. I think a lot of the 915 hard shifting legends are probably the result of pressure plate spring problems.

There is a poor design in the clutch. The pilot bearing guide tube has the trans input seal in it. Don’t forget to change that seal! Any leakage past that seal has the trans fluid migrate down the guide tube into the heart of the clutch assembly. It mixes with the clutch dust to form a sticky black goo. I drilled a small hole just ahead of the seal so if I ever get leakage it will hopefully leak out behind the throw out bearing.

theiceman

pics would have been cool .. but some interesting info .. how high did you have to get the back of the car ? did you take the rear bumper off ?

rusnak

The rear should be supported on 6 ton jackstands for stability. These also go high enough so that you don't have to remove the rear bumper or valance.

There are a lot of ways to remove the engine and transmission. I used a second jack for safety under the front of the transmission, just to make sure that I didn't hit the shift rod. I also used four jackstands, but lowered the front to make the rear high enough to clear the top of the engine.

Hladun1

I did not take the bumper off and I jacked the car up after the engine was on the floor jacks. The back bumper was ~3 ft off the ground to get the engine under it. When I pulled it out, the engine was about 8" above the floor.

For all the jack stands advocates, yes I did use jack stands for safety.

The responses to my post are funny, because I thought the important point in my post was that the spring plate fails and causes drag.

rusnak

I actually think thought the most important part of the post was the reminder to replace the input seal.

Hladun1

I don't disagree with the importance of the seal. My comment about drag is that in searching and posting here and on Pelican nobody had ever posted or could explain that drag (spin) was actually the result of clutch failure. Particularly since there are endless posts about how bad the 915 is to shift.

rusnak

Can you measure the wear on the flywheel and clutch disc? If you post pics, this thread can become a useful piece of material for others.