DK-40 Starting issues

[tkh159]

Well well well I have an update that some may find interesting.

I haven't touched the tractor since last post. Well I went to test the battery and it was reading 12.64 volts.

I turned the key to ON position and the glow plug indicator light came on. I didn't hear the clicking, clanking and ticking that I usually hear prior to starting the engine. The glow plug light went off and I turned the key to start.

The engine sputtered and spit as it tried to start. Massive amounts of exhaust came out along with the smell of unburned diesel.

I believe its safe to say my glow plugs didn't engage and that it may very well have been my electrical issue as mentioned by others.

So my guess is that it is the glow plug relay or preheating controller that may be malfunctioning. I haven't been out to test the glow plug itself and hope its not the glow plugs.

 

[ritcheyvs]

If your multi-meter has long leads (preferably with alligator clips), you can monitor the voltage to the glow plugs bu commenting a leas to the buss bar that connects the tops of the plugs (and the other lead to ground, of course). I had similar symptoms on my 2006 45s which turned out to be dirty contacts inside the key switch. Glow power was fine in "ON" but the plugs lost power when I turned the key to "crank". Later models use a different circuit that does not rely on the key switch for glow during crank, but mine does. Also, there is a spade connector where the wire connects at the back end of the buss bar; other owners have had this connection fail and even melt down from a poor connection.

In any case, start by actually measure the glow plug buss bar voltage with the key ON and in CRANK before you tear into anything. That's the sure test.

 

[tkh159]

If your multi-meter has long leads (preferably with alligator clips), you can monitor the voltage to the glow plugs bu commenting a leas to the buss bar that connects the tops of the plugs (and the other lead to ground, of course). I had similar symptoms on my 2006 45s which turned out to be dirty contacts inside the key switch. Glow power was fine in "ON" but the plugs lost power when I turned the key to "crank". Later models use a different circuit that does not rely on the key switch for glow during crank, but mine does. Also, there is a spade connector where the wire connects at the back end of the buss bar; other owners have had this connection fail and even melt down from a poor connection.

In any case, start by actually measure the glow plug buss bar voltage with the key ON and in CRANK before you tear into anything. That's the sure test.

Hey sounds like a good idea may have to get someone to read the meter as my leads aren't long enough to turn the key and read the meter.

 

[tkh159]

Tried to upload sone photos via phone but no luck. I'll upload the photos later if need be.

Anyway here's the scoop. As mentioned earlier I was going to purchase some relays that are what I believe are related to the glow plugs. The three I have are located behind the dash/firewall.

I removed them and relays prongs were HOT one relays prongs were cold. Keep in mind the tractor wasn't started and its 45 degrees outside.

That doesn't seem normal???

What would cause this?

Pictures will be added later this after noon.

 

[k0ua]

There is only one glow plug relay on a DK40. it is the center 70 amp relay on the firewall as you open the hood and look in from left to right is the starter solenoid relay, the glow plug relay, and the fuel solenoid relay.

 

[ritcheyvs]

I don't see why ant prongs should be hot. That implies the relay was consuming power, either the coil was being powered or the contacts had welded, causing it to conduct. As I recall, this saga started with a dead battery and you might have found the cause. Try to determine which relay it is by pulling the connector and then seeing what doesn't work. It should be obvious if it's the start relay and someone can observe the stop solenoid to see if it functions when the key is switched off. You can measure the glow plug voltage but there are additional (more subtle) problems that could inhibit glow power. Most relays have five terminals (2 for coil, a normally open contact, a normally closed contact, and incoming power). But I think you only have a 7-pin timer relay for the stop solenoid (no 5-pin relay for SS). So the number of pins on the hot relay may give a hint about it's function.

 

[k0ua]

I don't see why ant prongs should be hot. That implies the relay was consuming power, either the coil was being powered or the contacts had welded, causing it to conduct. As I recall, this saga started with a dead battery and you might have found the cause. Try to determine which relay it is by pulling the connector and then seeing what doesn't work. It should be obvious if it's the start relay and someone can observe the stop solenoid to see if it functions when the key is switched off. You can measure the glow plug voltage but there are additional (more subtle) problems that could inhibit glow power. Most relays have five terminals (2 for coil, a normally open contact, a normally closed contact, and incoming power). But I think you only have a 7-pin timer relay for the stop solenoid (no 5-pin relay for SS). So the number of pins on the hot relay may give a hint about it's function.

No, the timer functions are all electronic modules on the DK40se. The relays are all 5 pin on his rig. The only difference is the glow plug relay in the middle is 70 amp and the starter solenoid and the fuel stop solenoid relays are 50 amp and are the same relay. Assuming he has a DK40se...

 

[tkh159]

No, the timer functions are all electronic modules on the DK40se. The relays are all 5 pin on his rig. The only difference is the glow plug relay in the middle is 70 amp and the starter solenoid and the fuel stop solenoid relays are 50 amp and are the same relay. Assuming he has a DK40se...

All three relays I pulled are 4 pin. Two of the three were hot and I'll note their location with pictures. I'll have to load the photos tonight so I can better explain the relays. All three are positioned above the preheating controller box. I have only three mounted on this location.

Soooooo close to solving this issue.

 

[tkh159]

I don't see why ant prongs should be hot. That implies the relay was consuming power, either the coil was being powered or the contacts had welded, causing it to conduct. As I recall, this saga started with a dead battery and you might have found the cause. Try to determine which relay it is by pulling the connector and then seeing what doesn't work. It should be obvious if it's the start relay and someone can observe the stop solenoid to see if it functions when the key is switched off. You can measure the glow plug voltage but there are additional (more subtle) problems that could inhibit glow power. Most relays have five terminals (2 for coil, a normally open contact, a normally closed contact, and incoming power). But I think you only have a 7-pin timer relay for the stop solenoid (no 5-pin relay for SS). So the number of pins on the hot relay may give a hint about it's function.

Something is not allowing the glow plugs to work that much I know but why I unfortunately don't know.

Stop solenoid functions fine luckily.

The three relays I pulled all have 4 pins one which all pins run in the same direction horizontally or vertically depending on how you look at it. This relay was hot.

The other 2 relays theor pins are both vertical and horizontal.

 

[k0ua]

All three relays I pulled are 4 pin. Two of the three were hot and I'll note their location with pictures. I'll have to load the photos tonight so I can better explain the relays. All three are positioned above the preheating controller box. I have only three mounted on this location.

Soooooo close to solving this issue.

when you say hot, what do you mean? How hot? There should not be any current flowing in the coils of any of them with the tractor running. The starter solenoid relay is only energized when the engine is cranked. The glow plug relay has a cycle of 15 seconds of initial heating then about 15 seconds after startup in a "post glow" function. In other words the glow plugs are energized (by the relay contacts) about 15 seconds after startup. The fuel solenoid relay is only energized for about 1 second to pull in the high current fuel solenoid winding, then the low current winding of the fuel solenoid is powered from the key buss, so that relay has already dropped out. Since there should not be any current flowing in the coils, and hence the contacts should not be in contact during normal running operation, there should not be any heat dissipation. Heat coming off of the engine may make them warm, I don't know.. If they are hot... from electrical current, then something is wrong.