B7100 Pressure plate adjustment.

[michael496]

I split my little tractor this weekend because I thought the release bearing was bad. The petal didn't move very much. Turns out the tractor has a new clutch in it. The release bearing is fine.

Two things I noticed:
1) The bearing holder (sleeve) for the release bearing isn't moving smoothly, I can rock it up and down (not sure if that is bad) and the grease zerk is missing on it.
2) The fingers on the pressure plate do not appear to be raised very far.

My thoughts are that if the fingers are not adjusted correctly then there wouldn't be much movement in the clutch petal. How do I measure them for adjustment? I do not have the tool that the manual shows. Is there another method to adjust them other than trial and error. It only took a couple hours to take it apart but I'd rather not do that 2/3 times.

Does anyone have any insight into this? I'm thinking I may need a new sleeve.

Thanks in advance
Mic

 

[michael496]

I got the sleeve out and there are no seals on the differential end of it. I figure that is causing the movement. I'm still not quite sure why the petal would only move a little and wouldn't disengage the clutch.

 

[Stumpy]

There aren't any seals on the bearing carrier. At least I don't remember any on mine. Mine was a slightly loose fit (0.030ish) to the transmission input shaft but it doesn't need to be too tight. I can't make the judgment of whether it's worn out from here but that missing zerk says it hasn't seen grease in a while. I'd try cleaning everything with brake cleaner or something, replacing the grease zerk, and seeing if it's happier with grease. If anything was going to wear out I'd expect it to be the carrier over the input shaft it rides on.

As for setting the finger height on my machine there is an access panel on the right side of the bell housing so you can adjust the fingers with the machine together. Not sure if you've got that but I set them close to where I thought it should be, put it together and adjusted from there. Their position isn't too critical as long as you've got sufficient adjustment left in the linkage to set the free play properly.

If you can't get to them with the machine together then you can set it to spec before installation and then test it. The book lists the correct finger height for your machine as 1.764" to 1.819" off of the flywheel surface. Bolt the pressure plate to the flywheel without the clutch disc and use a cheap set of calipers (hardware stores usually have them) to set them in the middle of the range. They need to be within 0.012" of each other so they contact the throw out bearing evenly. Once set unbolt it, reinstall with the clutch disc, center it, put the machine together, adjust the linkage and see if its happy.

 

[birddogger]

You don't say how far apart this is other than split and the bearing carrier removed. Do you have the pressure plate removed and the clutch disc out?

This failure: "New clutch, pedal won't move far, clutch won't disengage"; sounds unfortunately too familiar to me.
Had a clutch replaced (because of those symptoms) and in 80 hours the same thing happened. Split the tractor myself this time (the pros weren't doing it right) and found: clutch disc shattered around the hub, a shock spring fell out jamming the pressure plate. Yeah, of course the pedal wouldn't move.

They hadn't replaced the drive bearing (pilot bushing) and this allowed the input shaft to wobble, stressing the metal around the splines in the clutch disc causing the hub to break and letting a spring free to jam the pressure plate.

Just so you know.

Look to possibly needing the flywheel machined and a bushing installed to secure a new pilot bushing. The input shaft should have some wiggle when free from the flywheel; but the bushing should hold the clutch disc and input shaft "on axis" so loads are evenly distributed.

Check the other end of the input shaft at the universal coupler (up under in the tunnel), there should be no up/down or left/right motion in the shaft as it enters the coupler. It is OK to display motion because of the front-end of the shaft wobbling now, but not in the coupler.

Check the end of the input shaft that enters the flywheel for wear. If it is severely worn or tapered from running without the pilot bushing, the decision arises, since you have the flywheel in the machine-shop do you A) buy a new input shaft and restore this to "OEM" configuration.
B) have the shop machine the shaft too, and create a new bronze bushing so the flywheel now mates up with the new diameter of the input shaft. ??

 

[Piker]

Check the "fork" piece that attaches to the clutch linkage. The ball-shaped ends that engage the throwout bearing carrier slots were worn flat. I built them back up using a wire feed welder & got them back to original shape. Eliminated a lot of slop in clutch pedal travel/adjustment. A small amount of play at the bearing is a lot of free play by the time ya get back to the clutch pedal.

 

[Dennis]

There are seals in the throwout bearing carrier and they were,for me, a pain to remove .

Probably also worth replacing the bellhousing shaft seal which is awkward to get at.

I used a pilot bearing puller to get my one out.

As birdog suggested , check that universal coupler ; mine was shot and caused clutch grinding after I put the new clutch in.