Problem starting my DK40

   / Problem starting my DK40 #1  

boomer613

Silver Member
Joined
Apr 25, 2012
Messages
126
Location
Northern part of AL
Tractor
Kioti DK40SE /W FEL
I am hoping someone can help diagnose my starting problem on my DK40. For the last year, it has been a pain to start. Basically I have to hold the gas pedal down for about 20 seconds "after" it starts, if not it will die. In other words, it will start but not keep idling. I replaced the positive battery cable (but not the negative or ground wire) 6 months ago and it seemed to help out somewhat but on very cold days I will run the battery down before I get the tractor to run or idle on its own without stepping on the gas pedal. Could it still be a battery cable problem. On some occasions, it will click but not turn over unless I move the key the stop and start several times. Has anyone experienced a similar problem with their DK40? I bought it in 2012. I currently have about 225 hrs. Thanks, Boomer
 
   / Problem starting my DK40 #2  
Cable usually prevents from turning over

I've also read about key switch issues

Are you saying that once you start to keep it running you need to give it throttle?

That I've not experienced before with a diesel

Once warmed up does it run well?

Joel
 
   / Problem starting my DK40 #3  
I am hoping someone can help diagnose my starting problem on my DK40. For the last year, it has been a pain to start. Basically I have to hold the gas pedal down for about 20 seconds "after" it starts, if not it will die. In other words, it will start but not keep idling. I replaced the positive battery cable (but not the negative or ground wire) 6 months ago and it seemed to help out somewhat but on very cold days I will run the battery down before I get the tractor to run or idle on its own without stepping on the gas pedal. Could it still be a battery cable problem. On some occasions, it will click but not turn over unless I move the key the stop and start several times. Has anyone experienced a similar problem with their DK40? I bought it in 2012. I currently have about 225 hrs. Thanks, Boomer

Well, everyone has an opinion, and here is mine. Your original running problem, is NOT a starting problem, and has NOTHING to do with electricity. Your problem has to do with fuel or air delivery. Once you cease cranking the engine, the electrical is out of the loop except for the engine stop solenoid, but if this was a problem there would be no fuel delivery at all. Your problems would seem to be related to the injection pump fuel rack or clogged fuel delivery in some manner.

As for the second problem, a likely place to start is the key switch itself. Try shooting some Fluid Film into the key switch or your favorite electrical lube. If that doesn't fix it, try replacing/rebuilding the switch. Another possibility is the starter relay on the firewall of the tractor, as viewed from the front it is the first relay on the left.

outside firewall.JPG
 
   / Problem starting my DK40 #4  
First is the way it is supposed to work:
Turn key to on and glow plugs will automatically come on for about 20 seconds & the glow plug indicator light in dash will be on.
Once indicator light goes off, crank engine to start then release key to run and glow plug light will come back on for another 20 seconds (approximately) to add post heat to cylinders to help fuel atomizing.

Your problem sounds like voltage problem either through battery connections or key switch or possibly both.
Battery ground is often overlooked and has been reported here more frequently than positive cable. While battery cables are off, have the battery load tested just to make sure it is not weak battery. Clean all cable and post terminals and follow the ground cable to where it fastens to the frame. Take the bolt out and sand frame paint to bare metal, reinstall cable and repaint it.
If still having problems the switch would be next to check or replace. Key switch on these, especially older models, have high failure rate too. many have had luck cleaning the switch, others simply replaced it. I have read on TBN that Kioti has a new part number change on the switch.

If the intermittent cranking problem gets resolved but still have to keep extra throttle added to warm up then check the glow plug function. May have bad relay or weak glow plugs.
 
   / Problem starting my DK40 #5  
First is the way it is supposed to work:
Turn key to on and glow plugs will automatically come on for about 20 seconds & the glow plug indicator light in dash will be on.
Once indicator light goes off, crank engine to start then release key to run and glow plug light will come back on for another 20 seconds (approximately) to add post heat to cylinders to help fuel atomizing.

Your problem sounds like voltage problem either through battery connections or key switch or possibly both.
Battery ground is often overlooked and has been reported here more frequently than positive cable. While battery cables are off, have the battery load tested just to make sure it is not weak battery. Clean all cable and post terminals and follow the ground cable to where it fastens to the frame. Take the bolt out and sand frame paint to bare metal, reinstall cable and repaint it.
If still having problems the switch would be next to check or replace. Key switch on these, especially older models, have high failure rate too. many have had luck cleaning the switch, others simply replaced it. I have read on TBN that Kioti has a new part number change on the switch.

If the intermittent cranking problem gets resolved but still have to keep extra throttle added to warm up then check the glow plug function. May have bad relay or weak glow plugs.

Come to think of it, there is a "post heat" to the glow plugs also. Even though the glow plug light goes out and you engage the starter and the engine starts. the glow plugs stay on for about 15 more seconds to keep the combustion chamber warm until normal combustion continues to heat it up. I had forgotten that.
 
   / Problem starting my DK40
  • Thread Starter
#6  
Thanks everyone for replying. I replaced my other battery cable (negative) yesterday and it did not seem to correct the problem. I will check the ground wire today. Once the engine is warm, it does seem to idle better, meaning I do not need to hold down the gas petal for 20 seconds to keep it running. As James Koua suggested it might be two problems. Could one of my problem be a neutral safety switch? I noticed that when I giggle to shifter, it seems to start, rather than just making a clicking noise but I cannot always replicate this.

Again, the tractor seems to run well after it starts up. No problem running it all day long. It just seems to have a starting and idle issue until it warms up.

I will stray some fluid film today in the ignition key. I will also monitor my glow plug light today while starting it.

Thanks,
Boomer
 
   / Problem starting my DK40 #7  
Mine runs rough for a few minutes when warming, pretty much all diesels will do that until they get up to operating temperature but I've not had to increase throttle to stay running, only start issues I've had were ignition switch, which I oiled and worked back and forth to fix, but it's still glitchy I need to take it apart and fix or replace, and one other time I had a issue which I thought was the neutral position sensor as you mention, I did get it to start a couple times by moving the shifter but it wasn't a reliable fix, turned out it was one of the relays under the hood, James shows them in his photo. I've had relay issues a times since which I've remedies by unplugging and plugging back in our sometimes wiggling the connections or tapping lightly on the relay itself. The relays are cheap enough it pays to keep a spare or 2 around. Again if the relay is your issue it will only fix the start issue, not the having to hold the throttle. That sounds like lack of fuel to me, diesel engine needs 3 things to run, fuel, air, and combustion which is created by compression, being low on fuel will make ignition harder, as would lack of air or lack of compression.

A cold engine will run rough and smoke more because it isn't burning fuel properly due to the cold engine components causing the compressed air in the cylinders to be cooler than optimal for getting good ignition out of diesel fuel, once warmed up they run smooth and stop smoking. Since opening throttle cures the issue that's likely the system if look at.
 
   / Problem starting my DK40
  • Thread Starter
#8  
Thanks for replying. I haven't had time to play with my tractor as it has rained the last 2 days. I might get out this weekend and try wiggling the relays as you and James suggested.
 
   / Problem starting my DK40 #9  
DK55 was having the same starting problems. I was also having problems with the stop engine solenoid not working. In the process of trying to fix the engine stopping problem, before paying $100 for a new solenoid, I replaced the safety start relay, it's a common 5-pin relay available at any auto parts store for less than $15.

The new relay fixed the starting problem which I think must have been a lack of power to the glow plugs. (It didn't fix the stop engine solenoid problem. :()

Good luck

I should add that the glow plug, dash light was doing just what it was supposed to do, so there was no indication that the non-working glow plugs were the problem.
 
   / Problem starting my DK40 #10  
I was wondering if Boomer613 ever solved the hard start problem. It sounds like the same issue I have with my 2003 DK55. I have to give it throttle while starting and it will smoke white for a good 5 to 10 minutes and has very low power. I have noted a lot of this complaint about the Kioti engines on this and other sites.

I have checked everything I could think of on the tractor. I removed the injector pump and sent it in for a rebuild. Nothing was found wrong with it. I sent in the four injectors and they were found to be working properly. I checked the compression of the engine and all four cylinders were well within specification. All of the glow plugs worked and were within specification. However, the glow plugs only work when the ambient air temperature is cold. I can't remember what the actual temperature has to be for the glow plugs. I put clear hoses on the fuel system to make sure there were no air bubbles. New fuel and filters did not solve the problem. The white smoke is not coolant since I do not lose any coolant or see bubbles in the overflow.

I just hope people make it a standard practice to make a final post discussing what they did to solve the problem. This will help other posters search for remedies.
 

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