John Deere 790 Pto

[z28clone]

The rear PTO will engage fine with nothing attached. But grinds when an implement is attached. I managed to get it to engage twice yesterday with no grinding, but not sure how. Pto Lever moves easy and only grinds at the last 1/4" of the top position. I read other posts and looked at the bolts through the screen on the right. Tolerance is slightly larger then the 0.60in. And they are too tight to move without fighting the moving flywheel. I tried waiting 30 sec, ive double clutched. When pto is spinning without an implement, pushing in the clutch does not stop it. Any other suggestions?

 

[beenthere]

Is this 790 a single clutch system or dual clutch?

 

[zzvyb6]

A lever or rod underneath the seat might be bent, deformed or unpinned at the transmission. There should be a little play in the knob when you pull it up for rear pto engagement. Same for mid-pto engagement if you have the kit installed.

 

[z28clone]

Dual stage clutch. With implement connected I disabled the pto safety switch so I can see if pto will run when tractor is off then start it with pto engaged. But with pto lever engaged the pto doesn't spin and will still grind if I pull up on the lever to the highest point in the slot. It acts like the pto gear isn't fully inserted in the drien gear. Any adjustment in the pto lever throw? I also think that the pto clutch might be frozen, but this latest test has me looking at the lever linkage.

 

[beenthere]

Let us know when you find out.

 

[z28clone]

Well the fix isn't what most of you would prefer, but I won't use the pto much and saved me alot of time without messing with the clutch or splitting the tractor. I was correct thinking the pto gear wasn't engaging inside the driven gear. So I ground the top end of the pto slot about 1/2" so I could bring the lever up higher. Tractor now engages the pto when shut off..with pto switch bypassed with jumper wire, I was able to start tractor with pto engaged and now I can mow a pasture with it. Starter didn't seem to struggle at all..seemed normal. Pto shaft to mower spun slow while starting and engine took off normally with pto running.