The Stovebolt Site Forums The Shop Area Driveline Bad clutch disk?

Hi guys, one problem fix...just developed another. Got the valves done and the head back on the truck and she was happy for about 2 weeks, then Murphy's Law struck.

Here is where I am at...the old truck started to chatter really back when taking off from a stop in 1st gear. Feathering the clutch helped but still did not feel right. She also developed a rattle squeaky sound when revving the engine with the clutch both engaged and disengaged. I was reading another members thread that had a similar noise and it turned out to be bad bottom end bearings. That got me very nervous. The only thing that didn't make sense in my case was that my engines oil pressure is very good.

So I started with moving parts outside of the engine and the clutch assembly was my first stop. I pulled the dust cover on the bottom of the bell housing and the small inspection cover on top and had a good look around. Everything looked OK, plenty of meet on the disk, but there was debris on the interior dust cover surface. I depressed the clutch pedal and held it down with a piece of wood. I crawled back under the truck and looked at the clutch and tried moving things around. Sure enough, the clutch disk spun freely with light finger pressure. I don't think that should spin because the splines in the center of the disk mount to the transmission output shaft.

I think the fiber disk separated from the metal part with the springs and spline opening. I've never seen something like that...am I on the right track?

Either way, the trans is getting pulled and a new clutch is going in...this is finally going to get me off of my lazy butt and install the 3 speed OD trans I have sitting in the garage.

If the transmission was in neutral, it would be normal for the clutch disk to turn with the pedal depressed. The clutch disk is mounted to the INPUT shaft of the tranny, not the output shaft.

I have blown apart a disk. Center hub broke away from the disk, but that was on a 7.3L Powerstroke that that develops WAY more torque than any 235 could.

Anyway, hope you get it fixed in short order.

Hi Kevin, I see what you're saying and the transmission is in neutral...but shouldn't that input shaft of the transmission spin too? If I turn the disk, the trans input shaft should spin or turn at the same rate?

When I move the clutch disk (with the clutch depressed to relieve tension), the input shaft of the transmission does not turn. The only thing I can see moving in the bell housing is the fiber disk..and it spins really easily. I can flick it in any direction with one finger and it will moves several inches.

Does the truck move when you put the transmission in gear and release the clutch? If so, the disc and the spline are still connected to the transmission input shaft. No discussion, no possibility of the lining and the clutch hub not being mated. Now- - - -have you checked motor mounts? The strongest likelihood that a chatter will happen on takeoff is from loose, broken, or deteriorated motor mounts.
Jerry

Thank you Kevin and Jerry.

I understand what you guys are saying now...sometimes it takes me a little while!

I'll start checking the other things.