JD 4300 Will Not Turnover

[gonediesel]

Hello, I have a JD 4300 that will not start. It will not turn over at all but battery is fully charged. I have read many threads with the same topic and many have replaced the "thermistor" behind the fuse box. I can't find a thread where they say thermistor replacement worked if the tractor turned over but didn't fire or if it didn't turn over at all. My issue the tractor will not turn over. This happened one other time over a year ago and after sitting a few hours it fired up. I have checked all contacts from the battery to to starter they are clean. Any suggestions are appreciated. GD

 

[RoyJackson]

That really sounds like a safety switch problem.
First, make sure the PTO(s) are not engaged
If that doesn't help, try unplugging and plugging the seat switch. Might be some corrosion in there and it doesn't take much.
If you have a hydro tranny jiggle the forward and reverse pedals a bit before and during cranking
If a gear or reverser transmission, make sure all levers are in neutral...don't forget the reverser lever (which is the one I normally forget about).

Hopefully, one of the suggestions above will solve the starting problem.

 

[beenthere]

How old is the battery?

 

[rekees4300]

From 4300 manual:
Starter will not work:

Loose or corroded battery connections.
Blown fuse.
Low battery output - check electrolyte level.
Neutral start switch faulty or not adjusted properly.
Key switch or starter faulty.
Gear shift lever in gear.
PTO engaged.

 

[Egon]

Are there any clicks when you turn the key?
Do the headlights work?
Have the fuses and relays been checked?
All the wireing harness been manually jiggled about?

With the key in the start position move all the control levers to see if anything happens.

All information others have already given.

 

[gonediesel]

Hey Guys, thanks for the replies.

New AGM battery - Installed last summer. Tractor is used year round and battery tested good. Not able to test under load of course.
All wiring have been checked from battery to starter. But have not checked any of the safety switches. Need to research this as I don't have a manual yet.
Fuses and relays - Fuses are good. Relays not sure how to check these. Are they all the same. I could stop into an automotive store and buy a couple to try.
Headlights - work
Dash lights - work
Dash gauges - work
Clicks - no clicks when key is turned. Dash lights light up but when key is turned no noise.
HST - I did press the forward and reverse pedal.
PTO - is not in-gauged (un-related but stalled the tractor out once a while ago with PTO in-gauged when tried to re-start no go. After about 30min screwing around realized what was going on. Good tip!)

I will check out the other suggestions. I will post in a day or two.

1. If someone could point me in the right direction on the relays. Are these standard relays or something only found at JD?
2. If someone could give me a quick run down on locations for safety switches. I can research if someone can just tell me where they are on the 4300.
3. Am I correct in that this does not sound like a thermistor issue?
4. Am I correct in that this does not sound like a fuel solenoid issue?

Thanks, GD

 

[Egon]

I wish I could help on checking relays but can't. If some are the same you may be able to switch them around for checking but keep track of their original position.

For safety switches just follow the electrical lines.

It does not sound like thermistor or solenoid issues?? Don't take my word on this.

The starter could be jumped directly to see if it turns over. Same goes for the solenoid. With that be carefull as it only requires full current to open. The thermistor current holds it open and is much less. It should click. The solenoid does not work a fuel valve. It deactivates the injection pump Pistons.

Last but maybe not least, pull the key switch and use a meter to check it. For this a diagram would help. You may also try and spray in some WD-40 to clean contacts.

 

[Soundguy]

any results?

 

[dfkrug]

1. If someone could point me in the right direction on the relays. Are these standard relays or
something only found at JD?

Relays are std auto type. All of them, IIRC. I never buy JD relays. I use stock Bosch.

The relay panel (where the thermistor is) gets really dirty and the contacts can get
resistive. You can swap them out if you know what you are doing. A service manual
showing the function of each is advisable.

The safety switches go bad. You can disconnect and short the wires to test them:
seat, PTO, neutrals. If the key is on and everything else is good, you will hear the
click of each safety relay if it is working.

 

[rekees4300]

2. If someone could give me a quick run down on locations for safety switches. I can research if someone can just tell me where they are on the 4300.

The neutral safety switch is located under the floor board on the right side of the tractor near the forward/reverse pedals. It prevents the tractor from starting if either pedal is depressed. The switch may be bad or the linkage with the pedals may need to be adjusted. I had that problem several years ago. I didn't know how to adjust the linkage so used a small ban clamp which provided just enough thickness to depress the switch.

 

[gonediesel]

OK I had some time today to play around with it. I still can't get it to run or turnover but there is some positive news. When the turn the switch I clearly hear a click from the fuel solenoid. Then I was also able to get it to turn over by jumping from battery to one of the wires running into the starter. So I feel the starter works. I have some things I tried below. Hopefully someone can point me in the right direction.

1. Neutral safety - This appeared to need some adjusting. I first jammed a screw driver in between the puck and the pedal to see if the puck need to be pushed in further? This did nothing. I then thought the puck must slide against the pedal to sense the location of the pedal. There was a 1/4 inch gap between the puck and the pedal. So I released the puck by about 1/4 inch so that it rides along the pedal. I really do not know how this functions. So my adjustments may not have actually done anything. I followed the wires as far as I could and they appear to be in good shape.



2. Seat safety - Same here the wires looked good as far as I could follow them.

3. Starter - The starter wires all look good as far as I could follow them. So I took a tester light and made contact with the red terminal (#2 on pic) on the starter - it lit up. I then made contact with the white wire running into the starter (#1 on the pic) with the key on and off. Tester light negative. I am not sure what this is but I was able get the starter to turn over by jumping to this. I followed this wire as far as I could and it looked fine also.



4. Switch - I pulled the dash off to clean everything up and to try and track some wires. I took the switch off and cleaned all the contacts. I placed the tester light in the only white wire going to the switch (thinking this was the same white wire at the starter) Tester light lit up. I then inspected the wire and both are numbered but are different numbers.



5. Fuse and relay panel - I pulled all fuses and relays. I cleaned the panel and all the relays which were pretty dusty. All relays looked fine and pins were clean. I then reinserted them but in different order to see if one was bad. Today I may buy a handful of them and try them out.

 

[Egon]

From your trouble shooting reports it would seem to be one of the position relative shut down switches. Start on the easiest accessible and so on. I believe seat switches are troublesome.?

Consider it as a yearly electrical maintenance program.

 

[beenthere]

What I am seeing in your item #1, is you are working with the adjustment of the cruise control magnet that holds the forward pedal in whatever position it is in when the cruise control is switched on. Don't think it is the neutral control switch.
But I may be wrong.
This is an HST tractor with the three transmission ranges, is it not?

 

[rekees4300]

What I am seeing in your item #1, is you are working with the adjustment of the cruise control magnet that holds the forward pedal in whatever position it is in when the cruise control is switched on. Don't think it is the neutral control switch.
But I may be wrong.
This is an HST tractor with the three transmission ranges, is it not?

You are correct. The neutral safety switch is located approximately 1 foot from the cruise control magnet toward the center of the tractor. It's not easy to find since it's located within the tractor's frame to protect it. But the good news is the bottom of the frame is open which allows access to the switch. The best way to find it is to manually depress either the forward or reverse pedal with your left arm while laying on your back looking up and watching the linkage move. You can see the switch being engaged/disengaged when a pedal is released/depressed. "Engaged" means the switch's button is pressed by the linkage allowing the tractor to start.

 

[coralhead]

My brother had a similar issue with his JD4300. A stick got jammed up in between the transmission the engine. There is a sensor up in between there that is hard to get to. He broke the connections off of it. It ran but after shutting down it would not start. ( I towed him out of the woods with my little Fergy 30.)

 

[gonediesel]

I had typed up a response this am and must not have hit post. Anyway after doing some more reading the "puck" is not the neutral safety switch. I did find it and also find the PTO safety switch. Both have been jumped and still no go. The only think left for me to check that I know of is the key switch. Which I have pulled and will test if I can find my voltmeter.

1. PTO safety switch - is jumped and confirmed working by hearing the relay snap when either jumping the switch or tripping the switch with the key on.
2. Neutral safety switch - is jumped and confirmed working by hearing the relay snap when either jumping the switch or tripping the switch with the key on.
3. Fuse Panel - I pulled the fuse panel to see if there were any chewed or damaged wires. Everything looked fine but very dusty.

 

[Egon]

Just a note on the safety switches. They also have to be checked for correct operation and position. Ie, does movement activate them and do they return to their neutral position?

 

[gonediesel]

Ok I tested the switch and it works. So I am now out of ideas. Any other suggestions? Again I can jump the tractor running jumper from the battery to the small white wire to the starter.

 

[Egon]

Wish I could help.

I have my own intermitent non start JD 4200hst. There are times the fuel/injector pump solenoid will not click ( engage ). The engine does turn over. Using a heat gun on the solenoid and pumping the primer lever works to get it started after which it runs
well and will start again if just shut off. Then, out of the blue, the solenoid has that loud snap and all is well. The solenoid enables/disables the injection pump.

Maybe it's the slap on the cowling or persuasive language I do not know. The solenoid has been replaced. Now I got two that work. One dealer says it has a thermistor; the other says not. If it does I still haven't found it to replace it. Looking at wiring diagrams, from manual, has not helped me.

 

[super55]

It almost sounds like the F/R potentiometers if either of them are sending a signal that the Forward or Reverse is depressed than it will send an override to not allow the tractor to turn over. All other electrical will work like the lights and turns but when turning the key you will get nothing.

I believe they are normally open switches switches so it is worth it might be worth disconnecting from underneath and see if it will start. If it starts up than you know it is one of the switches. Just be sure not to reconnect them when the engine is running if the tractor should does start.




I will see if I can pull up a schematic of the wiring system but it definitely sounds like you have a safety switch issue. JD's safety system is way over engineered where there is a multitude of things that can prevent the starter from turning.