Kubota L4600DT starting issue

[Sid Post]

I looked at the parts diagram and can only find a seat and neutral switch. We replaced the neutral switch and it's running again. I still don't know for sure if that was the problem. Would a neutral switch keep power from going to the gauges?

If I get up from the seat with the tractor in gear, the motor dies and the electrics are all off. If I sit down and catch the motor, things go back to normal.

 

[tammyemond]

Netural switch is only in the starter circuit along with starter and main key switch circuit. It does not feed gauges.

So does it keep power from going to the key switch, and therefore keep the power from going to the gauges?

 

[JC-jetro]

So does it keep power from going to the key switch, and therefore keep the power from going to the gauges?

In order to say it with certainty I need to look at the wiring diagram. I have factory repair manual for my MX-4700. If I get a chance I will look at it on Monday. I actually bought a L4600 DT but realized later it was not built in Japan. I then changed my order to Mx-4700. They have a lot of similarities . The key switch is always powered on but it routes power to gauges when you turn the switch on . In your vehicle when you turn the key on , instrument light will come on along with gauges and then next turn closes the start up relay to switch power to starter circuit. It is like that on my Ford 1700 also. I have not gone deep with my Kubota as I had no need to do it yet. Do you have a multi meter? that might come handy for diagnostics. Do you have WSM (WorkShop manual)for your Kubota?

 

[tammyemond]

In order to say it with certainty I need to look at the wiring diagram. I have factory repair manual for my MX-4700. If I get a chance I will look at it on Monday. I actually bought a L4600 DT but realized later it was not built in Japan. I then changed my order to Mx-4700. They have a lot of similarities . The key switch is always powered on but it routes power to gauges when you turn the switch on . In your vehicle when you turn the key on , instrument light will come on along with gauges and then next turn closes the start up relay to switch power to starter circuit. It is like that on my Ford 1700 also. I have not gone deep with my Kubota as I had no need to do it yet. Do you have a multi meter? that might come handy for diagnostics. Do you have WSM (WorkShop manual)for your Kubota?

No I don't have a workshop manual, and our cheap multi-meter doesn't work on the setting to check conductivity. I looked at the wiring diagram on Kubota Parts Lookup PartsByNet.com but I couldn't follow it. It is on two pages split between front and back and I couldn't identify the key switch. It looked like the wiring from the neutral switch went to the back lights. So I'm hoping it does kill all power otherwise we still have a problem that could rear it's nasty head at the most inopportune time.

 

[Williy]

Tammyemond can you print the sections of the diagram so you
can tape them together?

willy

 

[JC-jetro]

No I don't have a workshop manual, and our cheap multi-meter doesn't work on the setting to check conductivity. I looked at the wiring diagram on Kubota Parts Lookup PartsByNet.com but I couldn't follow it. It is on two pages split between front and back and I couldn't identify the key switch. It looked like the wiring from the neutral switch went to the back lights. So I'm hoping it does kill all power otherwise we still have a problem that could rear it's nasty head at the most inopportune time.

see if you can get a screen capture of the wiring and post it here for guys to takke a look at it. On the multi meter, what do you mean by conductivity, all wire and metal conduct. if you mean "short " or "open" in a wire then reading zero ohm means the wire is not broken and circuit has " continuity" . If your resistance aka Ohms is infinity then it means circuit is open or broken. You can make a test light with alligator clip to check voltage, close or open circuit just the same. Key switch , closes and opens the circuit. when you put the key in and turn one notch in your vehicle you will notice the oil pressure light illuminate. That is verification of intact circuit and as soon as engine is on the oil pressure would go fro normally closed to open, hence turning off the oil pressure light.

 

[tammyemond]

see if you can get a screen capture of the wiring and post it here for guys to takke a look at it. On the multi meter, what do you mean by conductivity, all wire and metal conduct. if you mean "short " or "open" in a wire then reading zero ohm means the wire is not broken and circuit has " continuity" . If your resistance aka Ohms is infinity then it means circuit is open or broken. You can make a test light with alligator clip to check voltage, close or open circuit just the same. Key switch , closes and opens the circuit. when you put the key in and turn one notch in your vehicle you will notice the oil pressure light illuminate. That is verification of intact circuit and as soon as engine is on the oil pressure would go fro normally closed to open, hence turning off the oil pressure light.

Sorry, I meant continuity not conductivity. Our multi-meter doesn't work on the Ohms setting or the setting specifically for continuity. The reading doesn't change between an open and a closed circuit. We need to get a new one or find the one my dad had.

 

[tammyemond]

see if you can get a screen capture of the wiring and post it here for guys to takke a look at it. On the multi meter, what do you mean by conductivity, all wire and metal conduct. if you mean "short " or "open" in a wire then reading zero ohm means the wire is not broken and circuit has " continuity" . If your resistance aka Ohms is infinity then it means circuit is open or broken. You can make a test light with alligator clip to check voltage, close or open circuit just the same. Key switch , closes and opens the circuit. when you put the key in and turn one notch in your vehicle you will notice the oil pressure light illuminate. That is verification of intact circuit and as soon as engine is on the oil pressure would go fro normally closed to open, hence turning off the oil pressure light.

 

[tammyemond]

Tammyemond can you print the sections of the diagram so you
can tape them together?

willy

I can, but I can't identify the ignition key switch.

 

[JC-jetro]

Tammy,

What you have there is not wiring diagram but it is wiring harness layout. It is good info to have but does not identify how circuits are made. Additionally if you have a list of item designator then it is difficult to identify what that block without index. Like on first screen capture 040,050 and 070 are all fuses but you would not know the rating or what circuit it is protecting. I will look at my WSM to see if I can find some useful info. Do you know the model # of your multi meter? I yet to see any multi meter that does not read ohm. That is the very basic whether it is a $5 Harbour Freight meter or $1000 RMS Fluke meter. Once you have ohms reading it can be used for checking continuity as well. I suggest you take a look at the link below. It will be helpful to diagnose and understand what's going on.