current shunt connection loose

[NVAM998]

Was working in the field and the M998 suddenly wouldn't start. Made a strange noise and I saw smoke coming from the battery compartment. The bolt head that is on the ground side (not the battery ground terminal side) of the shunt had arced and is a little loose. When I rotate it slightly I can feel there is a cable on the other side (it doesn't just spin). I worked it back and forth a bit and got a good enough connection to get the thing started (before this the headlights would not come on and the glow plug light would just flash). Got it back to the barn and parked it . I assume that I can loosen and clean the connections (after disconnecting the battery) and be OK again. Not sure how to reach inside the cab while I'm under the truck. Since it is single digits here I thought I'd double check that there isn't something else weird going on before I freeze my butt off again. Not sure how it worked loose and I assume it is just a pass through from the shunt to a cable but I didn't feel like lying in the snow to find out before I got it started. Is it just a nut and bolt through the shunt with a clearance hole in the sheet metal? The nuts holding the shunt in place spin so I assume those are nuts and bolts too and not a stud. Again asking so I can get a helper on hand before I crawl under and find out I need an extra set of hands. Thanks

 

[Milcommoguy]

Yes... You have it figured out. That bolt passes thru the tunnel to the inboard side, above the frame. Same with the positive only it has an inslator bushing. Many times radio accessories have wires / lugs connected there. In the de-mill process they may just cut them or (more trouble) remove the nuts, replace hand tight and call it good. I have pointed this out many times and it shows up with this same story. After all the nuts, bolts and fluids checks... check all the electrical bits, with the batteries disconnect. Follow the fat wires down to the starter too.

Bring a flashlight. It's the dark hole that needs checking, CAMO

 

[NVAM998]

Thank you sir!

 

[Mogman]

There is a large neg cable going from the transmission side of that stud to the starter, it carries all the negative load, probably best to have two people but I managed with only one.