B7200 - No Lights, No Glow, No Crank

It's been awhile since I last posted here. Life has been good, although with summer weather my orange tractors haven't been getting much of a workout since they are primarily snow movers.

This past weekend I had the B7200 HSD out for a run. Started easily, ran well, all appeared normal. The next day I started it, ran it for about 5 minutes, moved it and shut it down. Again, all appeared normal. An hour later I tried to start it to move it back into the shed and I got a nasty surprise. Pushed in the clutch, turned the key to the GLOW position for 20 seconds, then noticed the fuel gauge needle hadn't moved. Moved the key through the "RUN" position to the "START" position and got nothing, not even a click. Returned the key to the "RUN" position and noticed oil and amps lights were not illuminated.

Battery voltage was sitting at a lovely 12.58Vdc. Battery terminals are securely connected (well, one isn't now as I removed the ground terminal in order to begin troubleshooting). Before removing the ground wire I measured the same 12.58V on the starter solenoid terminal.

I've looked at the wiring diagram in the B7200 OPS manual and for the life of me I can't read that diagram. Even with glasses and a magnifying glass the image quality of the PDF version is just too poor to be useable.

I'm reaching out to the great gang here in hopes you might be able to point me in the right direction for a good probable cause for what appears to be a near-total electrical failure. Thanks in advance for your helpful replies.

I might be making some headway on the wiring diagram, thanks to some good posts on this forum. The battery is definitely good (stays up well above 12V with an automotive headlight load applied to it). In the wiring diagram I see the machine is wired so the battery + lead goes to the starter solenoid, then power for the rest of the tractor comes off that solenoid post to a fusible link before distribution to all other loads. Given that I have what appears to be a totally dead electrical system, there's a good chance the fusible link is at fault. Now I just need to figure out where that link is located in the tangle of wires, and what its amperage rating might be.

Thanks for all the very helpful posts, folks and your kind words of welcome, sheepfarmer.

A few minutes of digging around revealed what I'll call some "electrical idiocy". That's what happens when somebody who doesn't understand electricity at all gets in there and starts hacking and slashing the wiring. Well, in this case it was only the fusible link that had been hacked.

Under a wad of electrical tape I found a pair of red-ish wires which had been twisted together, poorly. The electrical tape had been intended as the mechanical bond to keep the wires together. Over time and exposure to heat from the close proximity to the exhaust manifold, the bonding force applied by the tape to hold the wires together weakened. The day of the "no lights, no glow, no crank" was the warmest day I had operated the tractor, pushing 30 degrees C. That extra heat was likely the straw that broke the camel's back. The loosely-twisted wire ends separated, thus interrupting the supply of power to the rest of the tractor.

The other night I returned to the tractor and, after finding this tape-covered wad of badness, squeezed it with my fingers and saw the instrument panel lights come to life. Easy temporary fix. Now that I know what's been going on with this connection I can surmise my poor warm-weather starts were likely a result of this flaky connection not passing sufficient juice to really heat up the glow plugs. Two and two have finally been put together, and the answer isn't three!

I'll cobble together something like Dave_eng's photo and re-install it with the wires pointing aft, getting them away from the heat of the exhaust, zip-tied to the bundle to keep them where I put them. Should be good for another 100,000 miles...

Again, many thanks for the helpful suggestions.