PTO Shift Problem

[Breeze]

Morning!

I have an L3700 with around 400 hours. After bush hogging I slowed rpm's and shifted out of PTO power but the PTO remained live. I finally shut the tractor down with PTO still live and upon immediate re-start, PTO was disengaged.

I checked cable from shift lever to case and it was not kinked. I removed cable at top end and was able to get a good amount of oil down the tube. Tried PTO shift, same problem.

Another site had a thread that suggested that the cable is not the problem, it is the shaft/shift lever on the transmission case that sticks and to hit it with penetrating oil, which I will do later today.

Anyone with a similar issue and what did you discover? Also, why will the PTO dependably go to neutral with an engine shut-down when shift lever/cable articulation won't. I guess I assumed this was a minor problem and am still hoping it is.

 

[Stubbyie]

I'm not intimate with your model machine, so allow me a question:

Do you actuate the PTO to 'on' in conjunction with your clutch by pulling the PTO 'on-off' cable while the clutch is depressed? I suspect you do but am interested if otherwise.

First guess is sticky clutch.

Does your machine have a condensation drip port under the bell housing and have you made certain it's open? Some may have a threaded port. Consult Owner's Manual before attacking to prevent dumping hydraulic fluid.

We've got both a shuttle shift and a hydrostatic and have noticed that sometimes the clutch doesn't act right at startup. After the first instance we've formed the habit of ALWAYS locking or blocking the clutch into the 'disengaged' or 'depressed' position when leaving the machine parked.

We get heavy fogs; if clutch left 'engaged' regardless of shifter position more often than not the clutch acts 'sticky'.

Similar to what happens in an old pickup when it's been sitting in wet weather: get in, push in clutch, turn key, and the durn thing jumps.

Please post back with your experiences and what you learn so we may all expand our knowledge of things orange.

 

[Breeze]

Thanks for the reply.

I depress the clutch prior to shifting in or out of PTO.

With the shift lever in the disengage position and the PTO still powered, if I depress the clutch pedal the PTO disengages. Release the clutch pedal and it powers back up. This is one reason I'm concerned because when I shut the tractor down with it stuck in engage, it is always disengaged when I restart. It seems to me that disengaging it with the clutch pedal while the engine is running would do the same thing?

Yes on the condensation port and on this model Kubota all you need to do is push the shaft to open the port. I haven't done this since the problem occurred but will do so later when I get under it to inspect the shift lever. I have never had any water come out in the past when I opened the condensate port.

I also depress the clutch pedal when starting the machine. I think there's a safety switch that makes this necessary but in any case there's never been an indication of clutch engagement with the pedal depressed and as stated before, depressing the clutch immediately sends the PTO into neutral.

Later today I'm going to get under it and inspect the works. I'll also hit the shaft/arm with penetrating oil and see if that does any good. I picked up an old post on TBN by an owner with a similar problem and the PB Blaster did the trick.

I did check the clutch travel as part of scheduled maintenance a year ago and it was right on the money. I'll probably check again........

I will post my results.

 

[Breeze]

After lubing the cable which didn't bring immediate relief, it was a week or so util I removed the mower.

At that point I sprayed the shaft and lever for the shift, at the transmission case side with PB Blaster and had my neighbor shift into and out of PTO, with the engine running.

After eight or so shifts I moved to the rear to observe the pto shaft as he continued to shift and it unloaded successfully each time.

Frankly I suspect it was the cable all along and it took a few days for the lube to work the entire length. The only test remaining will be when I remount the mower to insure that with that installed, it continues to shift properly. If it does, this thread is closed, if it doesn't I'll report back.

My advice is if you have some time on your tractor, remove the top end of this cable and lube as part of your maintenance routine. I didn't do anything fancy, just wrapped a rag around the cable shield and poured some motor oil into the space between the cable and tube.

Cheers

 

[RoperAndy]

Having the same issue on my 3800hst. Will try to lube the cable. Thanks for adding this thread!


Sent from my iPhone

 

[whitetiger]

Oiling the cable will not hurt but your problem most likely is where the shaft pivots thru the case. Spray some penetrate on it and shift it in and out. There is a coil spring around the shaft to return it to OFF. Pivot shaft sticks enough that the spring can not twist it to off. Very very common problem.