Deere 750 clutch stuck

[CoyPatton]

It's been a few years and no problems with the clutch until last week. The tractor sat for about 10 days during which time it was humid and rainy. Now the clutch won't disengage. Tried the chain and tree method and dragging it around the yard. Nothing seems to help. Next step is to split it open. What is the likely cause?

The cause is typically a bonding effect of the clutch plate to the flywheel via rust. It often does not take much—condensation from several hot days and cooler nights can do the dirty. In my experience driving with clutch pedal depressed usually does the trick. But if you have bern chained to a tree with pedal pressed down and no joy.
It is time to ip the ante—try hooking on a PTO implement and running it with the pedal depressed. If this roes not eork, look for an inspection plate and try a slight prying pressure to assist the clinch springs pulling back on it.
Hopefully the PTO implement along with driving will do the trick.

 

[pmsmechanic]

I had to split a 4020 for the same problem. What was happening was that water was running into the clutch housing where the transmission splits from the engine. A bead of silicone prevented the problem from reappearing.

 

[CoyPatton]

I had to split a 4020 for the same problem. What was happening was that water was running into the clutch housing where the transmission splits from the engine. A bead of silicone prevented the problem from reappearing.

The problem with the Yanmar built tractors is the vast number of places water can enter. The best cure on the Yanmars (even the JD ones) is to store them even overnight is to secure the clutch pedal in the depressed condition. This became such a well documented issue that later modrls came with a lever installed to lock the pedal down which maintains a distance between the clutch plate and flywheel. If the 750 in question does not have this lever, cut a piece of 2x to place between the floor pan and arm of the clutch pedal. A piece of wire rope and a rope clamp will allow it to hang below the floor if you forget to remove it and then find it later.
However the immediate issue is getting the clutch free. Hopefully it can be done without splitting the tractor. The load on the connection without the pressure plate applying pressure is the objective. That be low range and 1st gear with PTO pressure also or the other direction high range and higher gear with PTO pressure. A brush cutter should be good

 

[stephanadams]

Do not spray rust buster on it,that will ruin disc. Use a bungee,strap or rope to tie clutch pedal down as if full depressd with foot. Leave it overnight,a few days or month occasionally checking to see if clutch has released.

Speed Test​

 

[JD750ts]

Thank you all for the info.
Attached brush hog got in moving in low gear and then while moving shifted trans over to high , no grind at all increased RPM going up field with incline all the time clutch pedal pressed down .
This did the trick ,and released the clutch plate from flywheel

Saved my tractor and saved me a lot of money
Thank you all

 

[CoyPatton]

Great you have your clutch working. Now save yourself this hassle in the future, look for a small diameter “flip pin” near the clutch pedal, if present it was put there to hold the clutch pedal and thus the clutch in the open position.
If this “pin” is not present, get a block of 2x? to place under your floor board between the floorboard and clutch pedal rod holding the clutch in the depressed position.
This will prevent the clutch plate from “welding” to the flywheel as there will be no contact.
You can use a short piece of rope through a hole in the 2x tied to somewhere on the tractor (clutch pedal rod, floor board, anywhere that the block hanging does not cause issues.

 

[JD750ts]

Thanks again for the advice , have a piece of wood in there now but will look for the pin. Learned my lesson on this one