B2620 glow plug trouble shooting

[calhoun]

I have no power to any of the 3 plugs. Have indicator light on the dash says they are on. My ignition switch has no special turn to power the plugs they just come on when switch is on till you start then the indicator light goes out. Where is the fuse for the glow plugs. Tractor has 260 hours on it.
thanks this is my first post!!

 

[Pawnee]

Do you have the WSM?
I don't see it at Kubotabooks.

If not, the dealer may give you a copy of the schematic.

 

[Wull]

More than likely the glow plug relay.

The fact the indicator light comes on and extinguished after x amount of time tells me the timer relay is fine.

 

[calhoun]

Do you have the WSM?
I don't see it at Kubotabooks.

If not, the dealer may give you a copy of the schematic.

Thanks for your response dont know what a WSM is but going to the dealer next week

 

[calhoun]

More than likely the glow plug relay.

The fact the indicator light comes on and extinguished after x amount of time tells me the timer relay is fine.

Thanks for the reply. A relay would make since. Any idea where this would be located?

 

[sitric]

Thanks for your response dont know what a WSM is but going to the dealer next week

WSM = work shop manual. It along with a parts manual will show you where the relay is.

 

[North Idaho Wolfman]

There is NO timer, there is NO fuse, there is NO relay.
It's a simple wire from main switch to Glow plugs.

Since your getting an Indicator of it getting power to the glow plugs then it's most likely you have a fault at a connector or wire between the switch and the glowplugs.

 

[Wull]

I’d be very surprised if there was no relay or timer, I mean the glow plugs would be activated all the time then.

To the OP, when you turn the ignition on and the glow plug light comes on, does the light go out if you leave it in the on position? So don’t even try to start it, just leave it on.

I don’t know this tractor but going by 99% of glow plug circuits they have a relay and a timer of some sort, usually activating the glow plugs for roughly 10 seconds. I had one go on a Toro 5800 the other week, no power to glow plugs, yet light would come on and go out and it was the relay, replaced the relay and it was working properly again.

 

[North Idaho Wolfman]

I’d be very surprised if there was no relay or timer, I mean the glow plugs would be activated all the time then.

To the OP, when you turn the ignition on and the glow plug light comes on, does the light go out if you leave it in the on position? So don’t even try to start it, just leave it on.

I don’t know this tractor but going by 99% of glow plug circuits they have a relay and a timer of some sort, usually activating the glow plugs for roughly 10 seconds. I had one go on a Toro 5800 the other week, no power to glow plugs, yet light would come on and go out and it was the relay, replaced the relay and it was working properly again.

The key switch has a preheat position, as do most Kubota's.
Do you see a timer, relay or fuse?

 

[Wull]

Yes but he said in his first post that it doesn’t have preheat position on the ignition barrel and I can only go by what he says, if it were like the 2150 which I do know then I’d have said yes because you have to turn the key to that position and hold it there to power the plugs but he said it doesn’t have it or no special position for the glow plugs just turn the ignition on then start.

Check connectors and also remove the ignition barrel and check for continuity between glow plug wire at the Ignition barrel and the glow plug wire at the glow plugs

 

[Dave_eng]

There is NO timer, there is NO fuse, there is NO relay.
It's a simple wire from main switch to Glow plugs.

Since your getting an Indicator of it getting power to the glow plugs then it's most likely you have a fault at a connector or wire between the switch and the glowplugs.

Could it be that the owner is not using the pre-heat position on the key switch?
My version of the WSM shows such a position but the owner never mentions it.

Dave

 

[Wull]

Possibly but he says the glow plug heater light comes on the dash and my experience with the ignitions where you have to turn and hold it for it to preheat the light only comes when in this position.

 

[GreensvilleJay]

Thanks to NIW for posting the wiring diagram, ! I can SEE that the power wire from the 'T-splice' to the glow plugs is broken. NO timers, NO relays, NO 'computers' just good old SIMPLE wires.....

given in the original post....
1 ) battery, switch are good
2) dash glow lite, lights
3) no power (voltage) at the glow plugs

My conclusion is that the wire from the T-splice (black dot in wirig diagram ) to the 1st glow plug is bad.

I'd still like to see an 'electrical' subforum where wiring diagrams,test pages, etc. could be posted. Seems a lot of electrical problems could be quickly resolved if the information was easily available. If posters included their tractor model in the subject line, others could search for that in the electrical subforum and see if others have had the same or related gremlins.

 

[Dave_eng]

Possibly but he says the glow plug heater light comes on the dash and my experience with the ignitions where you have to turn and hold it for it to preheat the light only comes when in this position.

The wiring diagram does not show that differentiation as exists on the glow indicator systems.
This owner would see the light in the key switch start position also.
That is how I interpret the wiring diagram NIW provided earlier
Dave

 

[Wull]

Yeah maybe for the 2620, That’s the joy of having the schematic. I have a B2230 here the now which has the ignition barrel that’s on, preheat and start and when the key is to the run position there is no preheat light, the preheat light is only when it’s turned to the preheat position.

 

[Wull]

My ignition switch has no special turn to power the plugs they just come on when switch is on till you start then the indicator light goes out.

I still don’t understand this, this is what made me think it must be a relay whereas if it had been mentioned that it did have a turn to preheat ignition then it wouldn’t have led us down the garden path, well for the ones that don’t have the schematic.

 

[ve9aa]

Everyone should own a good multimeter and be trained to use it correctly.

It removes pretty much all doubt and guesswork.

 

[GreensvilleJay]

re:
when the key is to the run position there is no preheat light, the preheat light is only when it’s turned to the preheat position.

same as my BX23S and it makes 100% sense

you turn/hold the key to preheat glowplugs for say 5 second, then turn to start. NO need for more glowplug and all battery energy can go to the starter. Once running, key goes to the 'run' position.

simple, effective and cheap. Nothing complicated,works, same switch for 1,000s of tractors !

 

[Henro]

I’m wondering if the OP doesn’t realize that there are two positions of the ignition switch that are spring loaded?

Perhaps he thinks because he releases the key and it goes back to the run position that there’s not a preheat position that you need to hold before you fully turn the switch to engage the starter.

But he says the glow plug light comes on...hopefully he is measuring the voltage at the glow plugs when the light is on. Maybe he is just turning the key right through the preheat position…

 

[#40Fan]

Horrible screen grab from a video, but you can see the switch layout looks just like the one in post #15.