Clutch Failure

[AgTires4295]

Hey all, I know I'm a little late but Merry Christmas! If anybody is familiar with the clutch assembly on these Cubs, feel free to chime in. I was out mowing my field a few days ago and went to engage the clutch. The clutch pedal was shaking and there was a lot of constant grinding. The grinding became more pronounced when pressure was applied. I lowered my RPMs as low as I could get them, hesitantly pushed the clutch in and as quickly as I could to prevent any further griding, threw the trans into first and limped it back home. I have a video on my phone somewhere and will see about posting but am wondering if the clutch fingers are gone. I am not familiar with clutches and not sure about what has happened here. Any help would be amazing!

[John *.?-!.* cub owner]

Your description sounds as if the throw out bearing has failed, or at the very least is out of adjustment. Most likely failed though. It is a graphite block and when it wears down the clutch fingers hit the side of the bearing assembly, making a lot of noise and not releasing. It is lubricated via the grease fitting at the bottom, and the oil then seeps out of the wax base and soaks into the graphite from the rear.

[Bill Hudson]

Your description sounds as if the throw out bearing has failed, or at the very least is out of adjustment. Most likely failed though. It is a graphite block and when it wears down the clutch fingers hit the side of the bearing assembly, making a lot of noise and not releasing. It is lubricated via the grease fitting at the bottom, and the oil then seeps out of the wax base and soaks into the graphite from the rear.

I'm with John on this one. Splitting the Cub is in your immediate future.

Bill

[Bob McCarty]

Remove the hand hole cover on the bottom of the torque tube. You can then look at the throw out bearing and pressure plate with a flashlight. The graphite rim on the TOB should extend about 1/4" out from the metal housing. You'll probably see that the graphite is chipped and broken, or worn down to the metal casing.

Bob

[Dale Finch]

I agree with the above, but you might check the pedal adjustment to make sure you are not hitting the fingers with the TOB carriage. Slight possibility, but it does make that same heart-wrenching noise!!

[challenger]

If you have not recently adjusted the linkage on your clutch, the most likely reason for the scraping/grinding sound is a worn throwout bearing (TOB), as noted in the other comments. When the TOB bearing face gets worn down, the bearing housing will come in contact with the pressure plate fingers or housing. When the clutch is engaged, the fingers need to run on the face of the TOB to compress the pressure plate springs without the TOB housing hitting either the fingers or the pressure plate housing. As others have stated, you need to inspect the TOB face to see whether you still have a graphite face on the bearing that extends beyond the TOB housing. If there is no graphite left, you will need a new bearing, which requires splitting the tractor to install. If you still have some graphite material beyond the face, then you may wish to try adjusting the fingers on the pressure plate to see if this adjustment will give you some additional TOB service life. Each finger has a set screw with a lockdown nut. The set screw will move the finger back towards the TOB as you turn the screw in. The adjustment must be done uniformly for each finger to retain the same relative relationship with the other two fingers after all adjustments are complete. Once you have adjusted the fingers, you will likely need to readjust your clutch pedal travel. Make sure the tractor is in neutral and start it up. Push the pedal down SLOWLY all the way to the stop, which is the protruding cast iron peg on the torque tube, and listen for any grinding. If you hear grinding before you reach the peg, back off on the clutch just enough so the grinding stops. While continuing to hold the clutch in place, wait about 10 seconds and try to shift the tranny in gear. Go EASY on the shifter when you do, so you will not damage the gears if they are still turning. If you are able to shift the tranny smoothly without grinding the gears, then you can still use the TOB but you will need to adjust the linkage so the clutch pedal arm contacts the peg stop at the same place the pedal was successfully depressing the clutch in the preceding step. The basic pedal adjustment is made at the single bolt located in a slot where the clutch pedal arm intersects the horizontal rod going into the torque tube. By trial and error you should be able to find the sweet spot where the pedal arm contacts the stop and is still able to release the clutch sufficiently to prevent any grinding, either of the transmission gears or the pressure plate housing. If you perform the above clutch linkage test and there is no grinding on the pressure plate when the clutch pedal is fully depressed to the stop, but the tranny gears are still spinning, then you need to extend the clutch linkage adjustment to permit the TOB to further depress the pressure plate springs.