Zd21 pto appears to be frozen

[Steve NC]

I picked up a new to me zd21 mower the other day that has been doing a lot of sitting. I was told that its between 15-20yrs old. Mower only has 227 hrs on meter. I serviced the engine and it runs great however the pto lever will not move so I can’t engage the blades. Has any else run into this problem, if so what do I need to look for as a possible solution? Any help would be appreciated.

 

[Dustyx2]

Looks like no one has had this issue before. I haven't either, but if the lever won't move I'd be chasing the linkage and see why. May have take it apart to free it up. The clutch is hydraulic so all the linkage will be doing is working a hydraulic valve.

 

[Steve NC]

I think you are right Dusty. It doesn’t seem to be a common problem. I checked with my sister in law who runs the parts dept at the local Kubota dealer. She asked her shop people and called a couple of other dealers as well. She only found one other case of this happening. It appears to be the rod that goes into the transmission case itself causing the problem. The rest of the linkage assembly works fine when it is unhooked from that rod going into the case. She was told that on the other mower that it has been stored for a long period of time as well and it had started to rust in the housing. They told her that the rod wasn’t that difficult to remove and clean up but they ended up replacing most of the linkage due to the owner trying to force it and breaking some pieces. Hopefully i‘ll get some time over the next week to see what i can do with it.

 

[Dustyx2]

Thats kind of surprising that the rod would rust in the bore. I'd of thought that it should have had a good oil film on it. Hopefully you can get it freed up without too much trouble. I suppose NC humidity probably had something to do with it. Probably wouldn't happen here in the desert of WY.

 

[lugbolt]

I don't recall it much on ZD2x series

I had a lot of ZD3xx series with the same problem, but the dealer I worked at sold 50x more ZD3xx series than ZD2xx so that may have played the numbers

On the 3xx series the pto valve would become seized in the transmission bore. It's pretty simple design, remove the valve from the case and clean it up, reinstall it -and I always used a new o-ring, though the other tech at the time usually didn't and they never leaked? Anyway on the 3xx series you just need to remove a plate with a bolt in it, then use some penetrating oil at the ends of the valve that are exposed. Then use a wrench or plier to grab the lever connection end & wiggle it back & forth until it comes out. Some of them (I can't remember which ones, maybe the ZG series?) the valve won't come all the way out too much stuff in the way, but it comes out far enough to clean it up. Then it's just a matter of lubricating it with some clean transmission fluid, and reinstalling it.

On the 300 series you have to make darn sure the linkage is adjusted properly, and on those it's easy. Behind the filter (filter removed) you stuff a drill bit into a hole, then keep pushing on it whilst you turn the pto valve--once the bit passes through the valve, you then put the pto lever in "on" position, and try to hook up the linkage. If it's "off" a little, you bend it until it lines up, install the pin/clip and reassemble/done. On the ZD21/25/28 you can't do it this way because there ain't no filter up there (different transmission) so I am not sure how it's done on those?? But--nonetheless it is absolutely critical. If you get the linkage bent and reinstalled such that the pto valve isn't sending enough oil to the clutch, it can burn the clutch up in short order due to lack of oil. So with all that said, it would be advisable to look at a wsm to verify the valve to linkage adjustment.

 

[whitetiger]

I picked up a new to me zd21 mower the other day that has been doing a lot of sitting. I was told that its between 15-20yrs old. Mower only has 227 hrs on meter. I serviced the engine and it runs great however the pto lever will not move so I can’t engage the blades. Has any else run into this problem, if so what do I need to look for as a possible solution? Any help would be appreciated.

Disconnect the linkage from the PTO spool, remove the snap ring from the LH end of the spool Spray both ends of the valve with penetrating oil, then try turning the spool with a crescent wrench on the RH end of the valve. Do not use a lot of pressure trying to turn the valve. It probably will turn fairly easily. Turn the spool back and forth while trying to pull it out of the housing to the right. It is nothing more than a shaft stuck into a housing.
Once you get the spool removed, clean the rust out of the bore on both sides, grease the o-rings and reinstall the spool by hand. Its really very simple to do.

 

[Steve NC]

Thank you for your help Lug bolt and whitetiger. The rod was stuck in the case. A few light taps with the wrench and a few shots of pb blaster the rod was freed up. I removed and cleaned the rod, replaced the Orings and lubed it up before reinstalling. I can now turn the blades on with just the pressure of one finger. I’ll change the blades, fix a leaking tire and I should be in business.

 

[whitetiger]

Thank you for your help Lug bolt and whitetiger. The rod was stuck in the case. A few light taps with the wrench and a few shots of pb blaster the rod was freed up. I removed and cleaned the rod, replaced the Orings and lubed it up before reinstalling. I can now turn the blades on with just the pressure of one finger. I’ll change the blades, fix a leaking tire and I should be in business.