DK40SE HST Won't Start. Just cranks over

[Nick61]

Hi all. Once again, I have a tractor that wont start. She turns over great! Just won't fire. My last problem was a diode that was replaced. Last time the tractor wouldn't turn over when it got warm. Now, my issue is the opposite. I can wait for the glow plug light to go out, I turn the key to start and it will crank but it wont start. ??????????? I know I received alot of help from you all last time. I'm hoping we can fix this quick. I have a center aisle Breeze way that needs to be graded. pouring cement on saturday.

Nick

 

[ritcheyvs]

Start with the basics:
1. Is the stop solenoid retracting and staying retracted when you turn the key to on? You should hear a very distinct "clack" sound when you turn the key to ON and again when you turn it to OFF.
2. Are the glow plugs getting power when the glow light comes on? The light is independent of actual power to the glow plugs so a good light doesn't prove the plugs are powered; use a voltmeter at the top of the plugs to check.

Another easy test is to swap connectors on the two identical relays on the firewall. If the SS relay was bad it probably won't crank after doing this.

Also you can loosten one of the "b-nuts" at one of the injectors to see if any fuel is delivered when you crank the engine.

The most common root causes seen to be:
A failed relay (on the firewall) that prevents the stop solenoid from getting the "pull" pulse.
A wonky ignition switch.
A blown or corroded fuse.

But before you start swapping parts, determine "what isn't working."

Another possibility is a broken injection pump if your machine is in the 2005-2008 build year range. But check the basics first.

 

[k0ua]

Remember on the stop solenoid there are two coils and a ground connection. The "pull" coil is high current and is a 1 second pulse from the Stop Solenoid relay on the firewall, and the "hold" coil is a continuous voltage supplied by the key switch all the time that it is "on". A quick check with a voltmeter should see the pull coil 1 second pulse and the continuous voltage supplied by the key switch. Of course checking the glow plug voltage on the glow plug buss in another simple voltage check that is quick an easy to do. So you should have some answers with a voltmeter in your hand in about a minute and know what to start to pursue next.

 

[Nick61]

Thanks everyone, started at the relays swapped the two connectors, BAMM! She started right up. Replaced relay. All is good.
Thanks Ritcheyvs and K0ua.

Nick

 

[ritcheyvs]

Good deal!! The stop solenoid "pull" relay is only powered for one second so if it's marginal the SS may not retract (no second chances here). But the crank relay is powered as long as you hold the switch in crank. So sometimes a "bad" SS relay will still crank the engine; and sometimes it won't. Glad to hear you are back in business. These relays are common automotive items available at car parts places, like Autozone. You can get them on Amazon too in quantity for $2-3 each. I think the original relay contacts were rated for 30 amps so if you find one rated at 40 amps, it would be offer a better margin.

 

[Coyote machine]

Thanks everyone, started at the relays swapped the two connectors, BAMM! She started right up. Replaced relay. All is good.
Thanks Ritcheyvs and K0ua.

Nick

Good outcome.
Curious, did you get another OEM relay or an auto parts store similar type. I ask because you and others should know for future reference the relay you replaced is available in most auto parts stores, for likely less $ than those on a Kioti dealer's shelf.

 

[chuck172]

What is the amazon part # for the relays?

 

[ritcheyvs]

What is the amazon part # for the relays?

One member suggested this one Amazon.com: 5 Pack - EPAuto 3/4 AMP Relay Harness Spdt 12V Bosch Style: Automotive

 

[Nick61]

I had one that I bought at the auto parts store. I will order the 5 pack from amazon. Great price.

Nick

 

[Hope Caper]

I've heard a lot about these relays, are there any pictures floating about to show where they are and what they look like? I haven't had any problems yet but I own a 2005 DK 45 so it sounds like I will have to deal with this at some point. Same for the glow plug check and stop solenoid.