JD X749 Dying after 30-45 minutes

[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.