Is the ground shunt needed?

[freecr]

Hi all,

I have a M1079 and will eventually turn it into a camper. It's become a multi year project now and I'm still not too far along. Long story short... to increase usable space I have removed everything from in between the cab and box. There is a ground shunt that I'm wondering if it's needed. I think the only reason it's there is to feed an ammeter. There is a battery gauge in the dash's instrument panel, is this what feeds it? What is the down side to deleting the shunt?

 

[Suprman]

I think it's just for measurement. May be on it used with ice diagnostics. Are you planning on getting rid of the polarity box also?

 

[freecr]

By "polarity box" do you mean the four lug distribution strip that the 12 and 24 positive leads from the battery go to that was also under the spare tire mount/lift?

 

[coachgeo]

By "polarity box" do you mean the four lug distribution strip that the 12 and 24 positive leads from the battery go to that was also under the spare tire mount/lift?

That's it.

 

[freecr]

I am planning to add a solar system to the truck and was considering connecting the batteries for that via battery switches (one for the 24v and another for the 12v) so I could use either the 'truck' and/or the van batteries to start/run the truck. However, the main reason would be so I could use the engine's alternator to charge batteries if needed. Having a shunt between ground and frame makes me question that.

 

[freecr]

As far as the polarity box is concerned I was planning on using it. I don't really see a reason either way, but I didn't really consider deleting it. Is there a reason why I should keep it or remove it. Does it cause problems?

 

[freecr]

My truck is a 1994. It has the mechanical Cat 3116 engine. IDK, but I think the only computer diagnostic port would be for the transmission. I'm not all that concerned about the ICE diagnostics port any way but I don't want to cause problems somewhere else.

 

[freecr]

My truck is a 1994. It has the mechanical Cat 3116 engine. IDK, but I think the only computer diagnostic port would be for the transmission. I'm not all that concerned about the ICE diagnostics port any way but I don't want to cause problems somewhere else.

 

[coachgeo]

Find out if the M1079 had batteries for the box on it as well. If so then the schematics exist already on how to wire up using existing components. There has been a thread in here recent of a fellow with a M1079. He can answer if Box has it's own batteries like a typical Camper Box. Others may know as well and pipe in. If so.... the Technical Manuals (TM's) may cover the M1079 as well and have the wiring schematic etc.

 

[freecr]

I'm not that lucky. The boxes never had their own batteries. This will be a custom thing.

 

[Suprman]

The polarity protection box is there in case someone connects the batteries backwards. So you don't ruin anything. Except maybe the box.

 

[freecr]

Wow Suprman, your one of those early risers! If it's really there just as insurance for incorrect hook ups then its one less thing to mount and one less thing to go wrong. Now I am considering deleting it.

 

[Suprman]

I have kids so on the weekdays I am up at 5:30 to get everyone going. Sunday is my late day. I don't really like the box. But is serves a purpose when you have young mechanics working on these trucks in the military mistakes happen. I think it's basically a diode array. And if so you should get a slight voltage drop thru it. Plus it's more stuff to go wrong. And can be a pain to get to when it does.