John Deere 4100 Blowing 10 amp Fuse when PTO Engaged

[rhkrause]

I have a 2000 JD 4100 with 765 hours on it. I'm having an issue of a blown 10 amp fuse when the mid point PTO is engaged. Typically the fuse has blown after PTO is engaged for several minutes, however after replacing the seat safety switch it ran for about 15 minutes before the fuse blew yet again. The fuse blowing is the F2 fuse. A buddy of mine helped run the wiring looking for a short and none was found. While running the wires he was making sure the relays had good connections and after jiggling the starter relay the tractor would not start. Re jiggling it caused it to start. He's recommending a new K1 starter relay reasoning that the relay may be old, have a small crack etc. that may be causing the fuse to blow when the engine is warmed up.

Does anyone have any thoughts on this? I hate throwing money into parts trying to solve the problem, I'd rather find the problem and buy the part to correct it. I am not good with electrical issues, but my buddy is.

Thanks

 

[atsah]

I would first fix the connection/problem with the starter relay then make sure you have the same issue with the fuse blowing. Sometimes finding several problems while trying to diagnose the original problem can get confusing. Fix the one you know isn't right and go from there. Blowing the fuse is almost always an open shorted to ground. I assume the PTO issue is after your tractor is moving?

 

[rhkrause]

Yes the fuse 1st blew when mowing in reverse, the second time in reverse when mowing, the rest of the times it blew when it was driving forward and mowing. Went for the seat safety switch as the times it blew before that I was mowing on some rough terrain an was getting jostled pretty good. Replaced the seat safety switch and repaired a somewhat lose seat. The next time the fuse blew it mowed about 15 minutes before blowing on level ground. Thanks for the suggestions, I'll keep everyone updated on what we find.

 

[atsah]

Yes the fuse 1st blew when mowing in reverse, the second time in reverse when mowing, the rest of the times it blew when it was driving forward and mowing. Went for the seat safety switch as the times it blew before that I was mowing on some rough terrain an was getting jostled pretty good. Replaced the seat safety switch and repaired a somewhat lose seat. The next time the fuse blew it mowed about 15 minutes before blowing on level ground. Thanks for the suggestions, I'll keep everyone updated on what we find.

The fact that it happens after the tractor is bouncing tells me you have a short to chassis ground somewhere, try to narrow the circuit down to that fuse.

It's going to take some time to find it, you are going to have to actually see the open to find it unless it's at a connection point of some sort. Process of elimination is always useful with electrical issues.

Good luck and let us know if we can help.

 

[pmsmechanic]

Take a blown fuse and attach a 12 volt light bulb to the two spades. Plug it in to F2. Put some weight on the seat and engage the PTO. You might need to do this with the engine running or at least the key on. Start wiggling the wires untill the bulb goes out. Investigate that area thoroughly until you find the short.

You could have a bad solenoid or a loose internal wire in it.

 

[kencunningham]

If you have a clamp type amp meter, use that to determine the current draw. I'm assuming it is a electric clutch on the pto, which has a bad winding. If this is the case you will draw high amps which will blow the fuse after it heats up enough, but it will not blow it right away like a dead short. 2 cents.

 

[atsah]

Let the tractor set still for 20 minutes with the pto engaged to see if it is in fact the electric clutch, just to rule it out.

 

[pmsmechanic]

There is no electric pto clutch on these tractors. There is a solenoid that allows oil to flow to the wet clutch pack and that's what engages the pto. There are three solenoids in a row. one does the front wheel drive. one does the mid pto and the other does the rear pto. When the mid pto is engaged the rear pto also has to be engaged for the mid pto to operate.

Correction: There is an electric pto clutch when there is a front pto option installed.

 

[kencunningham]

There is no electric pto clutch on these tractors. There is a solenoid that allows oil to flow to the wet clutch pack and that's what engages the pto. There are three solenoids in a row. one does the front wheel drive. one does the mid pto and the other does the rear pto. When the mid pto is engaged the rear pto also has to be engaged for the mid pto to operate.

Correction: There is an electric pto clutch when there is a front pto option installed.

In that case i would check the solenoid with a clamp type amp meter. The solenoid may have a winding that has shorted, which will cause high current draw. Also the short may only show up with temperature changes.

Do you have a wiring diagram?

 

[pmsmechanic]

Do you have a wiring diagram?

I have wiring diagrams for the 41,3,410 series (service manual) but not for the 00 series.