6610S

[jbp]

Have an electrical problem with a 6610S. It starts and runs fine, but if the head lights are turned on the engine will die. The head lights do not work, but the flashers do work OK. Have replaced the light switch and key switch with no change. All fuses are OK so there is no short in the lights. The injector pump uses an electrical fuel shut off. The back main oil seal was replaced but all wiring seems to be plugged back correctly.
Any ideas appreciated, as it has me pulling out what remaining hair my bald head has.
Thanks in advance, Joe

 

[Jerry/MT]

I don"t know much about the specifics of your tractor however, the culprit is most likely that electrical shut off on the injector pump. It must be mis-wired so when you turn on the light switch you are turning off power to the fuel shut off valve. Look for a wrong connection. The power to the fuel shut off has to come off the start/run part of the key switch.

 

[LarryT]

Sounds like you have a high resistance ground on your headlight circuit. You can determine this with a volt meter. Attach the meter to a good ground and the positive terminal of the battery. Start the tractor and watch the voltage drop and then recover. It should recover back to 13.5 to 14 volts.
Then move the positive of the volt meter to the back of the light switch and see if you have the same reading as you did when you disconnected it from the battery. Verify that it is close to it. Then turn on the lights and see if the voltage drops and the engine shuts off. If the voltage drops below 9 volts the fuel will cut off and the engine will die. If you don't get the drop then attach the positive lead to the fuel valve control wire and try it again. But I suspect you will find that you have a high resistance ground that is causing a voltage drop that's killing the engine

 

[souNdguy]

my bet it is insuficient wireing to panel, dropping voltage when lamps try to come on, killing ip cutoff.

had the same thing onmy 7610s when I used the horn. horn kileld the tractor.

I disconnected horn power line and sourced off battery. problem went away.

they try to use 14awg wire in alot of that loom...

soudnguy

 

[souNdguy]

when i got my 7610s, it did the exact same when hitting the horn with lamps or flashers on. was insuficient power wireing.

try this test. run a jumper wire from battery hot to the lamp switch power input, now turn the lamps on.. bet they work and engine don't die when running. if so. either make the jumper permanent and leave paralleled tot he original power feed wire, or wire nut the power feed wire and use your permanent jumper. I reccomedn a 10awg wire for this purpose... not the wimpy 14awg stuff I see under them hoods alot.

post back to let me know if that helped. first test the lamps with the jumper in place to see if they come on before you actually do the run test.

( ps.. this really means there is an insuficient connection up the line in the harness.. which ain't easy to take apart. the redundant or repalcement jumper serves the same purpose and works.. been on my 7610s for oh.. 8ys with -0- issues now..

soundguy

 

[RodinNS]

I'm not sure if they use 10 series style electrics on those tractors or the 40 series style stuff. If it's 10 series stuff (and I suspect it is) you need to check the wire from the starter pos lug to the ignition switch. There's probably a bad connection at one of the junctions or a broken wire. You can probably confirm this fact by taking a GOOD DIGITAL multimeter and checking the voltage on the input side of the ignition switch with the key off, then engine running, then with lights on. I bet the voltage will drop each time... and when it drops below a certain level the fuel solenoid will let go. When you find the problem, fix it right and you'll be good for another 10 years.

Rod

 

[jbp]

Thanks for all the help. We are due for a winter storm with temps down in the single digits this weekend in west Ky, so won't try anything till it warms some. Its my hay hauler tractor so it doesn't need to be down long. Just like for things to work as they did from the factory.
Thanks again, Joe

 

[Tx Jim]

Would you interested in a Ford tech manual for the 10 series for $75? I don't need it any longer since my 5610 went up in smoke.

 

[LarryT]

Sorry to here about your friend. Why up in smoke?

 

[Tx Jim]

(quoted from post at 16:24:05 12/12/10) Sorry to here about your friend. Why up in smoke?

Wire going under cab shorted out and my employee stated he could get it put out before fuel got ignited. Nothing left but a pile of burnt metal. I had just installed 2 new rear tires about 1 month before the fire.