PTO blowing fuse

[ritcheyvs]

I am new to tractors so excuse the question... My first PTO attachment was a snowblower and the blower PTO shaft has a shear bolt built-in. Is this not standard on all PTO shafts. It sounds like the OP is facing an expensive repair rather than replacing a $2 shear bolt.

The DK series tractors engage the PTO using a hydraulically-operated wet clutch pack (like an automatic transmission). The electric solenoid controls the hydraulic flow to the piston that engaged that clutch. There is no shear bolt or pin on the tractor; all of the PTO shafts and gears are inside the transmission with only the splined drive shaft exposed.

The CK tractor PTO design is more like the setup you describe.

 

[GeorgeW]

This is a follow-up to this problem in hopes that it may be useful to someone else with an electrical problem. You can read the previous posts to see what was discussed. This picks up from there.

I discussed this with the mechanic at the dealer at some length. He concluded, based on all the tests that I had done, that it was most probably the solenoid, but would not commit to that without checking it himself. He also told me that he had never had a solenoid problem in his years at the dealership(he's been there a long time). He also told me that if I bought a solenoid and installed it, it would not be returnable since it was an electrical part(understandable). I decided to not take the tractor to him. A trip to take it and a trip to pick it up would be about 300 miles total. I could have the company that I work for pick up the part from the dealer and shuttle it to me at no cost to me for shipping. So, that is what I did.

When the solenoid arrived, I checked everything again. Everything was good up to the pigtail connector for the solenoid. Voltage was correct and fuse did not blow. Plugged old solenoid back up before removing it and fuse blew. Installed new solenoid, installed new fuse, and checked voltage again before plugging in the new solenoid. All good. Plugged in new solenoid, turned PTO on and fuse blew. NOW WHAT? What did I miss?

Ritcheyvs had suggested making sure the fuse contacts were clean, which I did. There are three switches in the circuit for the PTO, one on the dash, one on the fender and one on the lift lever to shut the PTO off when in automatic mode. Each of these switches have a pigtail connector. I had not checked them. Even though they were all very tight, I disconnected them, cleaned them as best I could and plugged them back up. Put a new fuse in, turned the PTO on and everything was GOOD.

Conclusions:
Check EVERYTHING in the circuit that you are having a problem with. I assumed that since the voltage was correct at the solenoid pigtail, that all was ok to that point. But that was with no load. It was failing with a load and I did not have a way to check it there with a load. Don't ASSUME anything.

I can only speculate that when the mower hit the stump, the jarring effect on the tractor shifted one of the connectors a bit so that it was failing under load.

I still love my Kioti. This is the first real glitch in the 14 years that I have had it and most of that glitch was operator error. I probably still came out cheaper than if I had taken to the dealer, and maybe I learned something in the process.

Again, thanks to all who gave input and suggestions. I hope that this might help someone else sometime.

 

[xcgreene]

This is a follow-up to this problem in hopes that it may be useful to someone else with an electrical problem. You can read the previous posts to see what was discussed. This picks up from there.

I discussed this with the mechanic at the dealer at some length. He concluded, based on all the tests that I had done, that it was most probably the solenoid, but would not commit to that without checking it himself. He also told me that he had never had a solenoid problem in his years at the dealership(he's been there a long time). He also told me that if I bought a solenoid and installed it, it would not be returnable since it was an electrical part(understandable). I decided to not take the tractor to him. A trip to take it and a trip to pick it up would be about 300 miles total. I could have the company that I work for pick up the part from the dealer and shuttle it to me at no cost to me for shipping. So, that is what I did.

When the solenoid arrived, I checked everything again. Everything was good up to the pigtail connector for the solenoid. Voltage was correct and fuse did not blow. Plugged old solenoid back up before removing it and fuse blew. Installed new solenoid, installed new fuse, and checked voltage again before plugging in the new solenoid. All good. Plugged in new solenoid, turned PTO on and fuse blew. NOW WHAT? What did I miss?

Ritcheyvs had suggested making sure the fuse contacts were clean, which I did. There are three switches in the circuit for the PTO, one on the dash, one on the fender and one on the lift lever to shut the PTO off when in automatic mode. Each of these switches have a pigtail connector. I had not checked them. Even though they were all very tight, I disconnected them, cleaned them as best I could and plugged them back up. Put a new fuse in, turned the PTO on and everything was GOOD.

Conclusions:
Check EVERYTHING in the circuit that you are having a problem with. I assumed that since the voltage was correct at the solenoid pigtail, that all was ok to that point. But that was with no load. It was failing with a load and I did not have a way to check it there with a load. Don't ASSUME anything.

I can only speculate that when the mower hit the stump, the jarring effect on the tractor shifted one of the connectors a bit so that it was failing under load.

I still love my Kioti. This is the first real glitch in the 14 years that I have had it and most of that glitch was operator error. I probably still came out cheaper than if I had taken to the dealer, and maybe I learned something in the process.

Again, thanks to all who gave input and suggestions. I hope that this might help someone else sometime.

Shorts, grounds, and poor connections can be a painstaking hunt sometimes, especially if the problem is intermittent. Have spent years, on and off, searching for some, where the ground was tucked away, only showing symptoms on brief occasions. We see a lot of this with poor battery connections here on the forum. Cables, connections look brand new, but rust under crimps, only having issues when warm, that sort of thing.

Great to see you’ve got her sorted

 

[LouNY]

Now that you have a spare solenoid you could disassemble it and find a manufacture or number on the coil :laughing:
As usually it is the coil that does fail on a solenoid not the plunger, many times a replacement coil can be located for much less then a new solenoid.

 

[ritcheyvs]

George, Maybe it's fixed and maybe not. A "dirty" fuse holder can cause a fuse to blow below the rated current as explained by Radio. Dirty connections for any of those switches should not cause a fuse to blow unless current leaks to ground, which is possible especially if wet and muddy. I obviously was wrong when concluded the solenoid was bad. If the problem returns, I recommend you get an ammeter and the schematic so you can isolate the issue with high confidence. You don't need to spend a lot of money on an ammeter as long as it has a 10 amp scale. This problem turned out to be a bit too subtle for the trial-and-error approach. You may have another chafed wire somewhere that got un-shorted (temporarily?) when you were moving wires to check those connectors. There is also a safety relay (to prevent starting with PTO engaged) that could be a factor.