DK45S keeps "stalling"

[buyerjohn]

Title says it all... not sure what's going on. I had the injector pump replaced about 3 years and 350 hours ago under warranty (I paid for labor - Rick Wallace was a huge help) but this is feeling eerily similar. Yesterday, the engine raced on me with no explanation...it was only for 5 seconds (or was i imagining things?!) but enough for me to link it to a injection pump failure.

Here are some details:

1. tractor stalls when I reduce power quickly either by taking foot off accelerator or reducing power using hand lever accelerator.

2. It runs with no problems provided I avoid doing #1.

3. When it stalls, it doesn't come to a quick stop but rather the engine just dies over 1-2 seconds... nearly like its running out of fuel.

4. It will not restart unless i turn the key to the off position first then turn back on. If I try to restart without turning the key to off first, it will not start. I believe this is because the injector solenoid doesn't operate unless the key is turned to off first but need to confirm this.

5. As a result, i think by reducing power quickly, the cylindrical rod inside the injection pump is moving to the off position and requires the solenoid to move it back to the fuel flow position. Could I possibly need another injection pump after only 350 hours on this replacement?!

5. If i stop the engine with the key, it will restart normally regardless of key start position.

6. I've cleaned the air filter, checked the fuel filter (new 30 hours ago)

I pulled the injection solenoid and it worked and the cylindrical rod inside the fuel injection pump is sliding back and forth normally though my helper said it didn't move the first time i turned the key.


Ideas folks? I'm in the middle of a tight deadline and am pulling my hair out on this one...

thanks, John.

 

[buyerjohn]

does the rod inside the fuel injector pump (which is opened and closed by the fuel injector solenoid) regulate the amount of fuel the engine gets? or is it just a no flow/full flow regulator?

anyone have other ideas of things to check here?

 

[IslandTractor]

Afraid I don't have much to add to your own analysis. Some of the other guys here are better on injector issues. Do a search limited to the Kioti forum on injector problems and you might find someone who has dealt with similar symptoms. Who is your dealer? Upper Valley Tractor in West Swanzey, NH is a very good dealership and they are TBN members.

 

[buyerjohn]

Afraid I don't have much to add to your own analysis. Some of the other guys here are better on injector issues. Do a search limited to the Kioti forum on injector problems and you might find someone who has dealt with similar symptoms. Who is your dealer?

I've done the searches and none talk about the symptoms I'm having...most discuss what I experienced 3 years ago when the tractor just quit running one day and wouldn't start again until the injection pump was replaced.

Rick Wallace originally sold the tractor but i don't believe he is a Kioti dealer any longer...he and his mechanic were invaluable in getting the problem diagnosed the first time. I see the $950 fuel injection pump is now $1,500...same with the rear glass I bought last year, it increased 50% in price too.

 

[IslandTractor]

I've done the searches and none talk about the symptoms I'm having...most discuss what I experienced 3 years ago when the tractor just quit running one day and wouldn't start again until the injection pump was replaced.

Rick Wallace originally sold the tractor but i don't believe he is a Kioti dealer any longer...he and his mechanic were invaluable in getting the problem diagnosed the first time. I see the $950 fuel injection pump is now $1,500...same with the rear glass I bought last year, it increased 50% in price too.

I would definitely call Rick. He sells Bobcat now so is still clearly in the "Kioti" tractor business. I'm sure Rick and his mechanics can talk you through other diagnostic procedures. If you need to trailer it to a dealer though I would bet on Upper Valley as Rick is about 250 miles from you while West Swanzey is only an hour or so.

 

[buyerjohn]

pictures of: 1) fuel rack after stall position 2). fuel rack after keyed off position.

Appears that the solenoid is not causing the fuel rack to move to the off position when stalling.


1.

2.

 

[Coyote machine]

If I were you I'd want to know the condition of my fuel supply to rule out possible contaminants that may have caused your first pump to fail and may still be contributing to your current symptoms. After all, if you end up installing a second pump you sure as heck don't want to travel this road a third time. Have you changed suppliers; do you store fuel on site and how much? Do you store it outside? Is it 'cut' for winter use?
It sounds from your description that you may have a solenoid issue rather than a pump issue. I would hope they are sold separately.
For further diagnosis I would ask Rick or your local dealer, for help with pinpointing the problem. First I would check the condition of the new fuel filter and see what might be visible contamination. Also make sure you don't have any suction side air leaks which could cause erratic run issues.

 

[buyerjohn]

Here's the latest that Michigan Iron sent me via PM...wanted to share their good help:

I have taken a quick look at your thread. The symptoms you describe do not sound like fuel injector issues. We would start our diagnosis by the following:

The reason you have to turn the key off and restart is because the fuel solenoid actually has 2 coils. A pull coil and a hold coil. The pull coil actuates for a round a second, then a lower draw hold coil holds the solenoid open. The pull coil seems to be fine, the hold coil should also be good since the only time you experience the issue is when you idle down. We would still test the solenoid coils.

Shutting off when you idle down would also lead us to check the governor spring. If you pull the side cover off the injector pump, you can see the governor arm with a double spring attached to it. Check to make sure the inner and outer spring are in tact.

Check the fuel filter. What you describe can be a somewhat failing fuel filter or a restriction in the fuel lines. This could cause the engine to starve for fuel.

Along the same lines, check the lift pump. It's the small round pump that runs off the fuel camshaft on the right side of the engine. Unfortunately, the lift pump is before the fuel filter, so it's possible there is some foreign "stuff" in the lift pump. You can disconnect the line from the lift pump to the filter and crank the engine to see of the pump is working if you don't have a fuel pump test unit.

Start with the simple stuff. It doesn't sound like an injection pump issue, it sound more like a fuel feed issue, possibly the governor. Start with the fuel system to satisfy yourself that fuel is being properly supplied to the injection pump. Then look at the governor.

Keep me posted, we'll try to help/

 

[buyerjohn]

and here's what I've found running various scenarios:

The fuel rail inside the injection pump moves freely after the tractor is stopped with the key. However, when the tractor stalls its because the fuel rail gets stuck and won't move to the right - no amount of force will move it to the right. I've confirmed this by watching the engine and testing it with the injection pump side plate removed. The lockup occurs even with the solenoid removed and the manual shut off lever/plate removed.

However, if I move the fuel rail slightly to the left manually (after it gets stuck), whatever is preventing it from moving to the right releases and the fuel rail moves to the right/both directions. Then, the tractor will start without having to first put the key in the off position. The reason I always had to turn the key off to restart is that the solenoid would kick the rail to the left, thereby freeing it up.

I can't see anything that's hanging the rail up other than the governor springs or missing teeth on the rail. I removed the 4 bolts from the governor plate and played with the springs to see if I could shake the rail free but it still wouldn't budge. The only thing that would move it to the right is first manually moving it to the left slightly either by hand or with the manual shutoff level.

When the tractor is stopped with the key, the rail is not in a stuck position and the tractor restarts without issue.

I think there are teeth missing (I found what looked like one in the injection pump) and when the throttle is released quickly, the rail goes past the broken tooth as it slide to the left and the idle spring assembly tries to push it back but isn't strong enough.

Could this action be cause by anything other than broken teeth?

What's strange is that it will only get stuck by revving, i can't manually get it stuck by sliding it back and forth...its like it needs to be under some sort of pressure as the fuel runs above it to force it down into the broken tooth or to hang up on a wayward spring/part.

Really quite amazing if this is my 2nd injection pump to only run 300 hours.

Thoughts?

John.

 

[IslandTractor]

You are over my head here. Did you call Wallace?