Blocking the clutch pedal

[kylemorley]

I have been wedging a block in to hold the clutch open a little whenever I leave the tractor sitting for more than a day. I learned this trick here, and it has made a terrific difference in drivability - almost like having a new lower reverse gear as the clutch doesn't grab and lurch like it used to, so starts smoothly with less throttle, and low speed operation is much easier.
While this seems to be a good and logical trick for a tractor that will not be used for a while, I am surprised that it makes so much difference even when the machine sits for only a day or two. Can anyone enlighten me as to what is happening inside that this should work so well? Is my clutch covered with oil? Rust? Is it worn out, and blocking the pedal just a stopgap?
 

[tn8n]

someone else will probably be able to explain it more in depth than i can, but to my understanding the biggest thing is, without it blocked the friction disc is in constant contact with the flywheel, and that causes it to trap moisture in the form of condensation. the disc will be warm from use and then as it cools it will collect the moisture, especially right now when it's cold and damp outside. a layer of rust will form on the flywheel, and if left for very extended periods of time, can even lock to two together as the friction disc is "porous" and the rust will actually form into it. each time you use the tractor that rust has to wear off before you get a good amount of "grip," and if the pressure plate is worn or weak to begin with it makes it that much worse.

as for if it a stop-gap measure, i would say even if it is, if it helps, just do it until it no longer helps and fix whatever needs fixing. HTH, Matt J.
 

[tracman]

[old]

Well I'll start with a check you should make. Look under the bell housing area as in under the clutch area. You should see a cotter pin hanging out there. Make sure it is free to wiggle around and is not covered with grease and oil. If covered and not free to move clean that area up with brake cleaner spray. That is the bell housing drain which drains oil and water out of the clutch area so as to help keep you from having those clutch problems.
Now to your answer. A sticking clutch can be caused by rust due to wear or just plain and simple weather. Rust will cause the disk to stick the the flywheel and or pressure plate.
Or the clutch area has oil and water in it due to the cotter pin clogged up and that in turn makes the clutch disk sticky so then you have your problem
 

[Dean]

Most likely you have two separate but related issues.

Small amounts of grease and very small amounts of oil on the clutch disc will cause it to grab upon engagement. Larger amounts of oil can cause the clutch to stick after periods (even short periods) of non use. Such stickage can easily be broken but the problem will be recurring until the issue is repaired. Large amounts of oil on the disc will cause it to slip under load.

Long periods of non use can cause the clutch disc to adhere to the flywheel and pressure plate surface due to corrosion if the clutch is left engaged. Clutch stickage caused by corrosion can be much more difficult to break free but is easily prevented by blocking the clutch open during long periods of non use.

About two months ago I took delivery of a new 2012 MF tractor. The Owners Manual recommends blocking the clutch pedal down during long periods of non use and a pre-formed metal hook designed to attach the clutch pedal to the footboard so as to hold the clutch in the disengaged position is provided in the tool box.

Dean
 

[HCooke]

Similar hook on my 1999 Kubota.
 

[souNdguy]

dean covered the topic well.

my ex-NH 1920 i got in 97 had a pre-made wood block on a string to block the clutch..e tc.
 

[Mashbox]

Buddy of mine had a later model JD compact tractor. We were looking at it the other evening and noticed it has a bracket that you pop up over the clutch pedal to hold it down. After checking the owners manual we found it recommends if you are not going to use the tractor for over a month to lock the clutch down. First time i have seen this on a tractor.