Question on John Deere 850 PTO

   / Question on John Deere 850 PTO #1  

Gary T72

New member
Joined
Jul 8, 2013
Messages
5
Location
Lithia Fl
Tractor
John Deere 850
I purchased this JD 850 tractor for some bush hogging and light discing. It has a 3 cyl Yanmar diesel and runs fine, however when I go to engage the PTO, there is a grinding of gears. The only way I hav been able to work around this is to completely shut down the tractor and re-start. Just as the engine fires and RPM's are lower i engage the PTO and press the accelerator to get the bush hog going. THis cannot be right. Any answers as to what I need to do? Thanks
 
   / Question on John Deere 850 PTO #2  
It has a 2stage clutch so I would say adjust the clutch.
 
   / Question on John Deere 850 PTO #3  
It has a 2stage clutch so I would say adjust the clutch.

Yep...and make sure you push all the way down on the clutch until you develop the knack for using a dual-stage clutch.
 
   / Question on John Deere 850 PTO
  • Thread Starter
#4  
Thanks for the reply. I tried adjusting the clutch. There is a rod, similar to an all-threaded rod, and a coupler that allows lengthening or shortening the travel of the clutch rod. I adjusted the rod to the length that it actually came apart at the coupler. I finally got it put back together, but no matter how I adjusted it it made no difference. Also, when I did have the bush hog running last weekend, I did bog it down a few times in case the clutch was stuck, but it didnt make any difference either. The work-around that I have found, that is higly preferably to clunking the PTO into action, that makes me shutter every time I hear it, is holding the PTO safety switch closed, and starting the tractor with the PTO engaged. I know this is not the right thing to be doing but I dont know where to go from here. Any suggestions greatly appreciated.
 
   / Question on John Deere 850 PTO #5  
It's better then just popping it in at low idle. Just popping it in well twist the the pto drive shaft. I twisted mine 2 times and that's when I found out I had a 2 stage clutch. It's been so long ago I can't tell you how I had to adjust my clutch. There are a nuumber of guys on here that have the 850,950, and 1050 that may see this and well look in there manual for you. All I can remember is I had to find a just the right spot and the peddle had to go all the way down and it was stiffer then the 1st part.
 
   / Question on John Deere 850 PTO #6  
Book calls for 9/16-1" freeplay in the pedal before you feel resistance-is it adjusted? What is the serial number(on tag below the PTO)? All early 850's had a single disc clutch up to -16,000
(and all 950's up to 20,000)
 
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   / Question on John Deere 850 PTO #7  
Thanks for the reply. I tried adjusting the clutch. There is a rod, similar to an all-threaded rod, and a coupler that allows lengthening or shortening the travel of the clutch rod. I adjusted the rod to the length that it actually came apart at the coupler. I finally got it put back together, but no matter how I adjusted it it made no difference. Also, when I did have the bush hog running last weekend, I did bog it down a few times in case the clutch was stuck, but it didnt make any difference either. The work-around that I have found, that is higly preferably to clunking the PTO into action, that makes me shutter every time I hear it, is holding the PTO safety switch closed, and starting the tractor with the PTO engaged. I know this is not the right thing to be doing but I don't know where to go from here. Any suggestions greatly appreciated.

You may already know this, but pushing the clutch halfway down disengages the PTO...all the way down disengages both the PTO and transmission. If you can push it all the way down and shift the gears normally, then the PTO clutch is probably shot. This assumes you have a dual-stage clutch, of course.
 
   / Question on John Deere 850 PTO #8  
I purchased this JD 850 tractor for some bush hogging and light discing. It has a 3 cyl Yanmar diesel and runs fine, however when I go to engage the PTO, there is a grinding of gears. The only way I hav been able to work around this is to completely shut down the tractor and re-start. Just as the engine fires and RPM's are lower i engage the PTO and press the accelerator to get the bush hog going. THis cannot be right. Any answers as to what I need to do? Thanks
Stand on that clutch you should feel a lot of resistance as you engage that second stage. It's there or your pto clutch would slip. 2 possibilities if you don't feel it. The fingers that engage with the throw out bearing need adjusting or are worn out/broken. Should be an inspection cover so you can look inside. On 2 stage clutches the throw out bearing hits the main fingers first and stops the tractor movement. when it hits the second set of fingers is disengages the pto clutch(much stiffer than main stage). on a lot of tractors you can get to the adjusters for the clutch to adjust for wear. Once it starts slipping it time for new clutches. some tractors don't use fingers but have adjustment bolts that move that 2nd stage pressure plate internally. more than likely you just need a few turns on the adjusters.
 
   / Question on John Deere 850 PTO #9  
You may already know this, but pushing the clutch halfway down disengages the PTO...all the way down disengages both the PTO and transmission. If you can push it all the way down and shift the gears normally, then the PTO clutch is probably shot. This assumes you have a dual-stage clutch, of course.

I apologize...got this backwards!
Halfway down allows shifting gears...all the way down for the PTO.
Had a brain fart when I posted that quoted posted.
 
   / Question on John Deere 850 PTO #10  
Hey guys is there a front PTO hookup for a 850 john Deere snow blower?
 
 
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