Where Is the Engine Stop Solenoid Located on a Kioti Tractor

Kioti Injector Pump problem

Common problem; Will not start after running
OK prior to turning it off.

Obviously there can be many reasons for this but in this case we will look at a common IP failure in the Kioti CK 25-30-and 35 with electronic turn off. First let's look at the injection pump and it's location. The pump is located on the forward right side of the engine seen here .

This shows the 3 plungers inside the pump from the bottom. The inner circles with the slots are the plungers and they operate up and down inside 3 gears controlled by a rack and pinion. If the rack is the whole way to the left (back of tractor) there will be no fuel to the engine and it will stop (or will not start as in my case) and if the rack is the whole way forward we get full speed. There is a spring on the left pushing the rack forward like this;

That spring housing can be seen here.

Under normal operation the throttle controls how far forward the rack will go. The rack has a pin resting on the throttle mechanism. That pin can be seen here inside the housing by removing the engine oil fill port.

Solenoid

There is another function built in to this module and that's the stop function. There is a solenoid on the right. The spring inside the solenoid at rest is stronger than the spring on the left. Consequently if the power is off to the solenoid it will push the rack to the left and the engine will stop. We can see the solenoid here, in this case activated.

The location of the solenoid.

It has two wires going to it. One is going to a holding coil that is only strong enough to hold it after it's been pulled in and the other is for the activation coil. Ground is the base so it will only work if grounded/mounted. Turning the key "on" causes the activation coil to get power via the "pull relay" as well as the holding coil but the activation coil will be disconnected internally to prevent overheating of the magnet. That circuit looks like this;

So what happens? Well, apparently the activation/deactivation of this solenoid causes the teeth on the plunger gears to break jamming the rack in the far left (off position)

So how do we know that's the reason our tractor will not start? Well, there are many ways. Lets look at the unit in whole.

The Orange lid (1) is the new engine oil fill port that is recommended for use rather than the top port. It's mounted with four screws (10 mm socket).

#2 is the injector pump itself mounted with four screws (12 mm sockets).

#3 is what used to be the manual stop. It's just used a lid now with no other function. 10 mm socket.

#4 is the stop solenoid that shut of the fuel when not activated.

If we remove the oil fill port #1 we can try to move the rack by pushing on the pin. It should move back and forth easily. Turning the key on and off would move the pin/rack forward.

Or we can remove the solenoid, stick our finger inside the hole and see if we have any spring tension on the rack. Before we do that I would recommend removing #3 in the previous picture, the lid for the old stop. There is a nylon guide for the solenoid that could fall into the engine when removing the solenoid and by removing this lid we can hold on to it when pulling the solenoid out.

So assume the rack is stuck, what do we do? Well, no matter what, we need to remove the injection pump to see why the rack is stuck. Sounds complicated, and it can be, but it should be straight forward. The main thing is that in order to remove the IP we need to remove the intake manifold. To do that I would recommend removing the hood although it could probably be done with the hood on.

In my case I had to work with the front loader mounted as I could not get it off but it would be easier to have it removed.

Also, remove the items in front of the manifold like the coolant container and the fuel filter. Two screws each, 12mm socket.

Now remove the pipes going from the pump to the injectors. I put tape over the holes to prevent junk from entering the pump and the injectors.

Now we are ready to remove the manifold. 5 screws 12 mm socket.

So here we are, ready to dig in to the pump but before we remove the pump we should remove the oil fill port, the solenoid, the lid for the old manual stop and the spring housing on the left (already removed here).

With everything removed we can now lift out the IP pump (maybe). In my case the rack had jammed in the far back position preventing me from just lifting the pump straight up. Having no other alternative I had to put a rod into the hole for the spring housing on the left and hammer the rack forward until I could get it out. I used the hinge pin for the hood. Fit perfect.

What happens is that the aperture inside the pump that adjust the amount of fuel to the engine fails. This is controlled by the 3 plungers in the pump, one for each cylinder. The plungers are operated by a cam shaft in the engine for its up and down motion and the amount of fuel to the cylinders depends on at what degree the plungers are turned in the pump while operating. It looks something like this seen from the bottom;