JD X749 Dying after 30-45 minutes

[Egon]

There may also be a thermistor involved. About ten dollars.

 

[Mike VS]

I assume that you have a connector that is used to hook the solenoid up to the tractor's wiring harness. Which side of that connector did you hook the test lights up to? What I'm getting at is if the connector was being tested also. I believe that the hold-in coil only draws about a half amp. You mentioned warm wires, and a half amp probably wouldn't warm up a wire. A poor connection or a bad crimp might. I might also be inclined to bench test the solenoid my itself to see how it performs long term.

I don't recall saying anything about a warm wire, there is nothing like that going on. I wired the lamp by slipping the wire into the plastic connector leading directly to the solenoid. The red wire was the hold in and the white was the start. There is a black which is ground. As for removing the new solenoid again and bench testing it we'll see, but remember the problem lasts for seconds and then it will restart. Yes, it will die again soon but how would you be able to reliably bench test it under these circumstances?

 

[Mike VS]

There may also be a thermistor involved. About ten dollars.

Talk to me... What is it and where is it? I know what a thermistor is but am not aware of any being on this unit. I was thinking right from the beginning that it was some sort of sensor.

 

[Mike VS]

I misread your earlier comment. I would take the solenoid out and apply voltage to it and let it set to see what happens. The more I think about it, the more I think it's doubtful that both solenoids would have identical performances.

The graphic below questions your bulb hookup. One way will check the connector and one way won't. It sure would be nice to have a diagram to see if other connectors are involved.

Since I'm not there and don't have a schematic, I'd be inclined to see if I could activate the injection pump manually so it's set to always run and see the the problem disappears or not.

View attachment 658444

OK, I see what you are explaining about the connector. Yes I put the wires on the solenoid side.
As for two solenoids acting identical, I contribute that to it not being the problem. Am I wrong?

 

[radios1]

maybe just keep it as it is, until enough members and yourself agree on the proper fix??.. there will be a lot of sidetracking first!..

 

[Mike VS]

maybe just keep it as it is, until enough members and yourself agree on the proper fix??.. there will be a lot of sidetracking first!..

I agree. I'm going to cut some more grass in a few days and will ponder it some more then.

 

[crazyal]

Is your fuel filter clear or is it the metal type? If it's the metal type when it dies I would quickly unscrew it and see if it's full of fuel. I had a similar problem on my backhoe and the tractor would just suck the fuel out of the filter. Once empty it would die. If it sat the fuel would slowly fill it back up. The fuel tank is a part of the frame and is tall so when it's half full or more the level is above the filter and when it was empty it's below. When empty the filter wouldn't fill back up. It turned out to be a bad fuel hose.

 

[Mike VS]

Is your fuel filter clear or is it the metal type? If it's the metal type when it dies I would quickly unscrew it and see if it's full of fuel. I had a similar problem on my backhoe and the tractor would just suck the fuel out of the filter. Once empty it would die. If it sat the fuel would slowly fill it back up. The fuel tank is a part of the frame and is tall so when it's half full or more the level is above the filter and when it was empty it's below. When empty the filter wouldn't fill back up. It turned out to be a bad fuel hose.

No, its plastic I think with a replaceable element, but it is transparent and I think that is a great idea. It's very accessible and would be an easy look see. Thanks!

 

[Mike VS]

UPDATE: Today I cut more very tall grass putting a moderate load on the motor. I started cutting and in exactly 55 minutes it died. The whole time I was cutting three things were being tested; First the fuel cap was unscrewed and was loose checking for a failure to vent. (This was done before but I'm starting to doubt my own results.) Also the test light was connected to the fuel solenoid and was brightly lit in my view testing any voltage failure to the now NEW solenoid. And listening to another contributor, I checked the transparent fuel filter housing making sure it was full before and after dying.
Upon dying the light never even flickered and stayed lit until the ignition was turned off. Also the fuel cap was still completely loose eliminating any fuel vacuum issues. And lastly, the filter housing was still completely full of fuel.
I waited 1 minute, restarted it and finished my cutting consuming exactly ten more minutes. It did not die again today. What am I missing here?

 

[mini14]

I have a tlb that has a 3tnv84 engine in it that acted similar. I replaced the electric fuel pump. It uses a pulse diaphragm type of pump that gets weak over time..i replaced it with hep-02 fuel pump, no problems since. Yours might be strong enough to pump a small amount of fuel. I would hear my old one running but the pulse was weak, I can hear a huge difference between the old one and new one. for $20 its worth the risk I think

 

[radios1]

UPDATE: Today I cut more very tall grass putting a moderate load on the motor. I started cutting and in exactly 55 minutes it died. The whole time I was cutting three things were being tested; First the fuel cap was unscrewed and was loose checking for a failure to vent. (This was done before but I'm starting to doubt my own results.) Also the test light was connected to the fuel solenoid and was brightly lit in my view testing any voltage failure to the now NEW solenoid. And listening to another contributor, I checked the transparent fuel filter housing making sure it was full before and after dying.
Upon dying the light never even flickered and stayed lit until the ignition was turned off. Also the fuel cap was still completely loose eliminating any fuel vacuum issues. And lastly, the filter housing was still completely full of fuel.
I waited 1 minute, restarted it and finished my cutting consuming exactly ten more minutes. It did not die again today. What am I missing here?

the only thing that will stop a diesel from running is cutting off the fuel.. either something in the fuel system is getting clogged over time, or the existing fuel pump is stopping over time.. adding a low psi electric fuel pump may solve your problem!.. they are NOT expensive..

 

[mini14]

I would be replacing the fuel pump. Or adding an electric one for $20

 

[jonsstihl]

You shouldn't have to add an electric fuel pump to the tractor to keep it running. It should keep running on its own. where is the fuel pump located with regards to the fuel filter and the injection pump. If there is fuel to the filter then maybe the problem is between the filter and the injection pump. I would be loosening up some of those hose connections looking for debris or something that would keep the fuel from getting to the engine.

I hate these kind off intermittent problems.

 

[Kyle_in_Tex]

it's not senders or sensors. the only thing that will stop a diesel is cutting off the air or fuel supply, does it have a lift pump?. that could be bad, if not, then you may have junk in your tank, or fuel lines, don't waste time with senders or sensors, it's the fuel supply!!..

The X749 does have a fuel sender pump. Part Number AM135286. It might have a pickup filter on it too. But let me tell you a quick similar story. I was working on a Diesel Kawi Mule. Same intermittent problem. After much grief, I found the crud in the fuel tank and the metal pickup tube had crud growing around the bottom of it.

I have a picture but it won't let me upload it. Tried 3 times.

 

[ruffdog]

Just wondering...what are the wires going to the air restriction indicator for? Just to light a dash light or can it shut the engine down?

 

[ruffdog]

Just wondering...what are the wires going to the air restriction indicator for? Just to light a dash light or can it shut the engine down?

I'm not seeing any dash light tied to the air restriction indicator...then, what are the wires for? Does the OP see any red in the air restriction indicator that would indicate a plugged air filter?

 

[Mike VS]

I have a tlb that has a 3tnv84 engine in it that acted similar. I replaced the electric fuel pump. It uses a pulse diaphragm type of pump that gets weak over time..i replaced it with hep-02 fuel pump, no problems since. Yours might be strong enough to pump a small amount of fuel. I would hear my old one running but the pulse was weak, I can hear a huge difference between the old one and new one. for $20 its worth the risk I think

I was thinking of that today while cutting. I wasn't sure if there was a fuel pump separate or built in to the injection pump. I guess you answered my question.

 

[Kyle_in_Tex]

Fuel Sender in tank
New P/N
FUEL LEVEL SENDER, WITH ANGLED CAP
Part Number AM136610

 

[Mike VS]

Ok everyone, I think I'm narrowing it down. As for the fuel pump I'll see what is there and check the electrical connections and especially the fuel lines. Now that everybody is mentioning it, the one problem I had with my JD5300 was when it suddenly died, and was caused by the most repulsive looking crap in the fuel pick up line. That's where I'm heading tomorrow when I can.

 

[Mike VS]

I'm not seeing any dash light tied to the air restriction indicator...then, what are the wires for? Does the OP see any red in the air restriction indicator that would indicate a plugged air filter?

Yea, I thought of that... No, all green and a super clean filter.