L3400 not getting fuel

[racesnake]

Intermittent failure to start began in late winter. It has gotten worse since then. First thing it did was to replace the fuel filter and bleed the system. After dong this it started and ran. I shut it off and immediately tried to start it again and it would not start. I checked the fuel cap vent, rebled the system and it still wouldn't start. Later on I tried and it started. This has happened several times since then.
I understand that the fuel shutoff solinoid has a run coil and a start coil. I can feel the solinoid open when I turn the key to on. The engine seems to run when I turn the key to start it but quits when I turn the key to the run position. I feel that I have an electrical problem but can't seem to find it. Any help will be greatly appreciated.
Dave

 

[Jim L.]

1) I would check for 12V at the solenoid harness connector both start and run pins using a test lamp or voltmeter.

2) check for ground connection at solenoid using ohmmeter or test lamp.

3) Running a separate fused cable from battery and ground to solenoid and checking that solenoid moves. It may be possible to do this without a separate cable by removing the solenoid and providing a path to ground.

That should help to narrow it down.

 

[racesnake]

1) I would check for 12V at the solenoid harness connector both start and run pins using a test lamp or voltmeter.

2) check for ground connection at solenoid using ohmmeter or test lamp.

3) Running a separate fused cable from battery and ground to solenoid and checking that solenoid moves. It may be possible to do this without a separate cable by removing the solenoid and providing a path to ground.

That should help to narrow it down.

Thanks, Jim...when I turn the switch from off to run I hear and feel the solinoid activate. Which coil is this? The run or start coil?

 

[Jim L.]

Internally, the solenoid has a coil for high current during field build up (pull). Once the field is stable, then a hold coil is all that is needed (hold). By having two coils, power and heat are minimized.

You should be getting 12V at the solenoid connector when the key switch is in either ON or START position. This would show a good switch and that safety circuits are working correctly.

 

[racesnake]

Internally, the solenoid has a coil for high current during field build up (pull). Once the field is stable, then a hold coil is all that is needed (hold). By having two coils, power and heat are minimized.

You should be getting 12V at the solenoid connector when the key switch is in either ON or START position. This would show a good switch and that safety circuits are working correctly.

Understood! Thanks, Jim.

 

[racesnake]

Well I got a chance to get back on my no start problem today. Removed the shut-off solinoid and tractor started right up. Checked the 2coils in the solinoid to ground and both showed. Continuity. Hooked the electrical cable to the grounded solinoid and watched the plunger rod for retraction. When I turned the key switch to on the rod retracted. When I turned the switch to start it extended and then retracted. When I turned the switch back to on it extended, retracted, and then extended. When I turned the switch to off it retracted and then extended. Something I found out while dicking around with the switch - the tractor will run in the start position and if I quickly turn the key off and then back on the sucker will run in the normal (run) position! Can anyone make any sense out of this?

PS: also can hear a relay clicking under the cowl when manipulating the key switch. Is this in the fuel shutoff circuit?

 

[Diydave]

Well I got a chance to get back on my no start problem today. Removed the shut-off solinoid and tractor started right up. Checked the 2coils in the solinoid to ground and both showed. Continuity. Hooked the electrical cable to the grounded solinoid and watched the plunger rod for retraction. When I turned the key switch to on the rod retracted. When I turned the switch to start it extended and then retracted. When I turned the switch back to on it extended, retracted, and then extended. When I turned the switch to off it retracted and then extended. Something I found out while dicking around with the switch - the tractor will run in the start position and if I quickly turn the key off and then back on the sucker will run in the normal (run) position! Can anyone make any sense out of this?

PS: also can hear a relay clicking under the cowl when manipulating the key switch. Is this in the fuel shutoff circuit?

Just a guess on my part, I would try a new ignition switch... Just had a similar problem on my isuzu npr diesel. It was the switch. A side note, if you have a heavy key ring, with lots of stuff on it, it wears out switches sooner.

On a chevy volt, this could be lethal...

 

[racesnake]

Thanks, Dave...I, too, think its a faulty switch.