JD 997 blue wires that connect to starter - one burned off today - any ideas?

[Wheel House]

I'm new to the forum.

I have a used John Deere for a week for a demo before deciding if I want to keep it. It's a 997 with 1200 hours and a bagger. This is my second day with it. Today when I went to start it, I turned the key to let the glow plugs warm up, and noticed a burning smell and some smoke coming up through the engine cover. I disconnected the battery, the bagger and opened up the hood to discover some burned wires connected to the starter. I'm hoping that the wire just had the insulation wear through, grounded itself and went up in smoke. I can easily repair the wire, but I'm concerned if I should be looking for something else wrong as well. The mower is pretty clean overall, and being that I've only had it for two days, I really don't know a whole lot about it. I do know that it mows like nothing I've ever experienced. It's a monster.

The blue wires come join on a single jump ring that connects to the terminal on the starter. The other end of the blue wires connect to two legs of red wire that has some heavy clear insulation at the joint. I have not traced the red wires. I have no manuals or schematics, so I don't want to proceed with a repair without some idea of what these wires do and why they might have burned off (if not from a break in the insulation).

I'm including a picture to give an idea of what I'm describing.

Thanks for any help given.

Shayne

 

[Willl]

It appears you burnt your 'fusible link', which would be the last link before smoking your wiring harness.

Seek help. F this up and it could get expensive.

 

[Blaneypark]

If it is a DEMO take it back. Have the dealer fix the problem.

 

[Wheel House]

Will - thanks for the insight. The tractor still starts and drives though (just drove it out of the barn to have enough light to see what was going on). Would it still run with a burned fusible link? I burned a fusible link on my Land Cruiser once and NOTHING worked. It was a dead horse. I'm not going to take any chances though.

BlaneyPark - good advice and I'm going to follow it.

 

[Willl]

Will - thanks for the insight. The tractor still starts and drives though (just drove it out of the barn to have enough light to see what was going on). Would it still run with a burned fusible link? I burned a fusible link on my Land Cruiser once and NOTHING worked. It was a dead horse. I'm not going to take any chances though.

BlaneyPark - good advice and I'm going to follow it.

Yes, your right, if indeed it is/was a 'fusible link', nothing would be 'alive'.

Looking closer, do I see butt connectors and such ?, don't look stock.

Was this the only 'small' lead to the positive side ?

 

[Willl]

The tractor still starts and drives though

Everything else is normal ?, charging ?

 

[Wheel House]

Yes, your right, if indeed it is/was a 'fusible link', nothing would be 'alive'.

It still seemed to run fine. I didn't run it for long.

Looking closer, do I see butt connectors and such ?, don't look stock.

The connectors are not the typical butt connectors you see at a auto parts store. They look original to my untrained eye. It is a strange configuration though. Heavy red wires connect to the thinner gauge blue wires that all end in a ring connector. It's hard to make out the connector through the heavy clear insulation/wrap that joins the red and blue wires. The blue wiring with the ring connector is just odd. The rest of the wiring and the engine compartment all look clean and unaltered.

Was this the only 'small' lead to the positive side ?

There are three ring connectors total that connect to the positive post on the starter. The other two are red wires and look of decent gauge (12 maybe).

I have an email into the equipment dealer explaining the situation. I really like the mower overall. It's just what I was looking for in terms of taming my 5 acres of grass in short order. My 3 wheeled Ferris out front mower will stay for some banks and tree work, but a 997 is in my future. Hopefully this one will work out.

 

[Willl]

Untill we know what's down stream from that burnt lead, all bets are off.

Something DEFINITELY went to direct ground.

Is it 'aftermarket' ?

Can you trace to its end ?

 

[Wheel House]

I really need a service manual. The dealer is calling me around noon to discuss. I'm pushing him to have him drop the mower at a John Deere service center.

I can't tell if the blue wires are aftermarket. I don't see any mods to the mower that would require additional wiring. Everything is very stock / factory looking everywhere else. The blue wires that burned off do seem a little out of place. They are spliced to the red thicker gauge wire and are terminated together with a ring connector. When the ring connector is connected to the starter, the blue wires form a bit of a "loop". I can't find any other wiring on the machine that isn't tucked away in the hard plastic protective sleeves. Nothing else is forms a loop of any sort. This loop of blue wire (when it was whole) is within 3 or 4 inches of the exhaust. I really don't see how it could touch the exhaust, but it could get rather hot there. I don't see any moving parts in the area that the wire could have gotten pinched by. There is matching blue colored wire of the same gauge used in other places on the wiring harness. The only other ring connectors are the other two that connect to the starter and one that goes over to the alternator. They are all a little different in the way they are terminated and the colors used for the insulation at the termination. Hard to tell if this one I'm having issues with is factory or not. I'm leaning to the side that it is factory. I want it to be factory.

The best I could trace the blue wires/red wires it up into the "fuse panel" on the firewall. It goes into one of the actual blade fuse blocks. I believe it's the "F3F4F5F6" block shown in the picture.

There are four fuses in that block and they all look fine. I really think this blue wire lost some insulation and grounded to the chassis in this area. There is plenty of metal around for it to find, and the loop it formed is always asking for a little more trouble.

I'll follow up with whatever conclusion is determined.

Untill we know what's down stream from that burnt lead, all bets are off.

Something DEFINITELY went to direct ground.

Is it 'aftermarket' ?

Can you trace to its end ?