JD 870 starting problem

[warhawk07]

As the subject line suggests, i developed a starting problem with my 870. Ran it it all day yesterday, and as i was driving it back to my shed where i park it, the unit completely shut down. no electrical power. turn the key, nothing. checked the battery compartment and discovered the positive battery cable popped off the battery, i re attached the cable and now the engine won't fire. it turns over no problem.

its a very clean unit with only 400 hours on it. prior to this issue, the unit started in two cranks, even in cold weather. i don't have a shop manual....just ordered one this morning....wondering if i blew a fuse or something having to do with the fuel pump?? any help on where to start diagnosing the problem is appreciated. thanks

 

[wore out]

As the subject line suggests, i developed a starting problem with my 870. Ran it it all day yesterday, and as i was driving it back to my shed where i park it, the unit completely shut down. no electrical power. turn the key, nothing. checked the battery compartment and discovered the positive battery cable popped off the battery, i re attached the cable and now the engine won't fire. it turns over no problem.

its a very clean unit with only 400 hours on it. prior to this issue, the unit started in two cranks, even in cold weather. i don't have a shop manual....just ordered one this morning....wondering if i blew a fuse or something having to do with the fuel pump?? any help on where to start diagnosing the problem is appreciated. thanks

There is a fuel shutoff solenoid mounted externally on your injection pump.

When you initially turn the key to "start" it needs to "pull in" and remain "pulled in" while the engine is running.

When the (+) battery cable fell off while the engine was running and (presumably) the alternator was charging a fuse may have blown due to overvoltage causing an overcurrent condition or due to the battery cable end shorting to ground.

I would check all the fuses, if OK look for any wires or "fusible links" (IF used) that may have overheated/melted.

 

[warhawk07]

There is a fuel shutoff solenoid mounted externally on your injection pump.

When you initially turn the key to "start" it needs to "pull in" and remain "pulled in" while the engine is running.

When the (+) battery cable fell off while the engine was running and (presumably) the alternator was charging a fuse may have blown due to overvoltage causing an overcurrent condition or due to the battery cable end shorting to ground.

I would check all the fuses, if OK look for any wires or "fusible links" (IF used) that may have overheated/melted.

appreciate the reply going to be a week or two as i don't live near the machine. i will start with the fuses and work from there

 

[warhawk07]

There is a fuel shutoff solenoid mounted externally on your injection pump.

When you initially turn the key to "start" it needs to "pull in" and remain "pulled in" while the engine is running.

When the (+) battery cable fell off while the engine was running and (presumably) the alternator was charging a fuse may have blown due to overvoltage causing an overcurrent condition or due to the battery cable end shorting to ground.

I would check all the fuses, if OK look for any wires or "fusible links" (IF used) that may have overheated/melted.

Ok im a little more educated today than yesterday.....couple new questions. Bear with me as my day job is in commercial banking, Im a half a...sed farmer on the weekend ha. Just trying to gather as much info as i can on this as the tractor is located 300 miles from home at my hunting property. And no dealer anywhere close either so i plan ahead with parts purchases etc Id like to get this figured out without multiple trips

Found a copy of the electrical diagram. Power for the fuel shut off solenoid runs from battery to alternator to key switch to the fuel shut off relay and lastly to the solenoid. It doesn't run through the fuse block like the PTO, seat, trans neutral switches etc If its not fused, how is the circuit protected??? Does the relay have a circuit breaker feature to it?? If so, does it reset somehow if working properly??? Just wondering if I have to do something to get that relay to reset. thanks

 

[warhawk07]

Ok im a little more educated today than yesterday.....couple new questions. Bear with me as my day job is in commercial banking, Im a half a...sed farmer on the weekend ha. Just trying to gather as much info as i can on this as the tractor is located 300 miles from home at my hunting property. And no dealer anywhere close either so i plan ahead with parts purchases etc Id like to get this figured out without multiple trips

Found a copy of the electrical diagram. Power for the fuel shut off solenoid runs from battery to alternator to key switch to the fuel shut off relay and lastly to the solenoid. It doesn't run through the fuse block like the PTO, seat, trans neutral switches etc If its not fused, how is the circuit protected??? Does the relay have a circuit breaker feature to it?? If so, does it reset somehow if working properly??? Just wondering if I have to do something to get that relay to reset. thanks

Sorry correction....power for the fuel shut off solenoid starts at the battery to STARTER (not Alternator as noted in previous post)

 

[wore out]

Sorry correction....power for the fuel shut off solenoid starts at the battery to STARTER (not Alternator as noted in previous post)

How many wires to the fuel shutoff solenoid, 3 is typical.

Can you post a photo or scan of the wiring diagram you are looking at?

 

[warhawk07]

How many wires to the fuel shutoff solenoid, 3 is typical.

Can you post a photo or scan of the wiring diagram you are looking at?

Thanks for the reply....

 

[warhawk07]

How many wires to the fuel shutoff solenoid, 3 is typical.

Can you post a photo or scan of the wiring diagram you are looking at?

according to the diagram yes there are 3 wires as for the unit itself....im assuming its original and has 3 wires. by the time i got the unit back into the shed Saturday, it was late so i didn't mess with it at all. trying to get back up there this weekend so will know more then

 

[used red MN]

Ok im a little more educated today than yesterday.....couple new questions. Bear with me as my day job is in commercial banking, Im a half a...sed farmer on the weekend ha. Just trying to gather as much info as i can on this as the tractor is located 300 miles from home at my hunting property. And no dealer anywhere close either so i plan ahead with parts purchases etc Id like to get this figured out without multiple trips

Found a copy of the electrical diagram. Power for the fuel shut off solenoid runs from battery to alternator to key switch to the fuel shut off relay and lastly to the solenoid. It doesn't run through the fuse block like the PTO, seat, trans neutral switches etc If its not fused, how is the circuit protected??? Does the relay have a circuit breaker feature to it?? If so, does it reset somehow if working properly??? Just wondering if I have to do something to get that relay to reset. thanks

What protects it? The somewhat horizontal section of the wire near the starter has two rectangles in it near each other. Those are plugs, in between them is a fusible link; that is section of wire reduced in size from the rest of the circuit. If there is a short in the circuit that section burns in two before any of the rest of it is damaged. There is a slim possibility that it could be burn out or not conducting power now.

 

[warhawk07]

As the subject line suggests, i developed a starting problem with my 870. Ran it it all day yesterday, and as i was driving it back to my shed where i park it, the unit completely shut down. no electrical power. turn the key, nothing. checked the battery compartment and discovered the positive battery cable popped off the battery, i re attached the cable and now the engine won't fire. it turns over no problem.

its a very clean unit with only 400 hours on it. prior to this issue, the unit started in two cranks, even in cold weather. i don't have a shop manual....just ordered one this morning....wondering if i blew a fuse or something having to do with the fuel pump?? any help on where to start diagnosing the problem is appreciated. thanks

Ok got back to fix this over the weekend and I had a blown 3a fuse Fuse replaced and tractor starts no problem. Appreciate the feedback thanks