JD 790 Stopped Running

[brazbrat]

Good morning,
Yesterday I was carrying a load of dirt up my hill when my JD 790 went quiet.
I checked the fuel, oil and water. I tried restarting the tractor, it will turn over but it won't fire up.

The tractor is 4 years old with 175 hours.

Thanks

 

[Egon]

Did you check for plugged fuel filters, fuses or safety switch operation?

 

[George2615]

Since you were using it at the time it stopped it sounds like the fuel filter is plugged and stopped fuel flow. Another cause could be a plugged air filter. When was the last time they were replaced?

 

[brazbrat]

I checked the fuses and air filters earlier this morning.
I will replace the fuel filter later today and try again.

Thanks!

 

[brazbrat]

George,
I replaced the air filter last summer along with the oil and filter.

I have never replaced the fuel filter, I guess it's time.
Is their any special proceedures for replacing the fuel filter?

Thanks

 

[George2615]

Not familiar where your 790 filter is. On my tractor its in the back about a foot under the fuel tank. I change mine 1x per year. Shut off fuel valve, remove and replace filter, open valve, open my bleeder screw on the filter housing to let air out and turn my key on a few times to cycle the fuel pump to refill. Yours may be different. The owners manual should tell you how to do it if you have one.

 

[brazbrat]

The 790's fuel filter is located near the fuel pump above the fuel strainer and shut-off valve. I'll get the proceedure when I pick up the filter at the JD dealer.

Thanks

 

[brazbrat]

I'm heading to the JD parts store to pick up the filter.
I'll let you all know how it goes this afternoon.

Thanks

 

[grnspot110]

Don't forget to check the fuel shut-off! Last summer I was driving my 790 around the edge of a field at the farm, just died! I looked it all over, found nothing wrong. It would start & run for 5 seconds or less at a time. I went after the pickup & trailer, got it loaded a couple feet at a time. Called the area dealer & took it to them that afternoon. Turned out that apparently a sprout had hit the fuel shut-off, turning it nearly off. ~~ grnspot

 

[brazbrat]

I replaced the filter, cleaned the strainer, checked the fuel cut-off.
The tractor still won't start. I disconnected the fuel line feeding the filter, fuel is pumping out. It is apparently not making its way to the engine.

 

[brazbrat]

I'm moving on to the fuel shut-off solenoid.
I found a test that was posted on-line that I'll try...

Don't start the tractor, but try turning the key to the ON position and then turn on the headlights and see if the fuse blows...

If the fuse doesn't blow
Check the solenoid
Fuel Solenoid Gound Test
1. Key off
2. separate connector at solenoid
Check continuity between harness side of connector and ground at battery negative post
Must be 12vdc...if so replace solenoid otherwise poor ground...clean and repeat
Fuel Shutoff Solenoid Holdin Test
1. Turn key on
2. push solenoid in and release...It MUST STAY IN
If it doesn't proceed...
Fuel Shutoff Solenoid Voltage Test
1. Turn Key on
2. Check for voltage at connector to solenoid...should be at least 9 volts
If not, reverify your ground and if that's okay...REPLACE SOLENOID

 

[brazbrat]

I disconnected a fuel injector supply line after the solenoid valve.
When I turned over the engine I saw no fuel.

I found a 3 amp fuse blown... it should have been the first thing I looked at.

I bled the fuel lines and the engine is running great, thank to everyone who responded to my post.

I'm back to work!

 

[George2615]

Glad you got it going again. Sometimes it is and sometimes its not the simplest thing but its usually the last thing you find. Just like finding lost car keys, they are always in the last place you look.

 

[whpenner]

Mine just did the same thing with the same symptoms. It cranks well, lots of fuel coming out of the hose at the engine, but no start.

It was running yesterday and about 3 seconds after I dropped it to idle and climbed off the tractor, it stopped. I haven't been able to get it to run since.

Any suggestions other than the ones above?