Need help on a 59 B 12/24 parallel series switch

[Countrylife 35]

Hi All, 

I am hoping someone has an idea here as I am a bit confused. At some time someone cut the batteries off the truck (4 6volts) and I am adding 2 12v. 

Here is a diagram of how it is currently wired. I know this is wrong because there are currently 3 neg terminal ends and one positive that goes straight to the starter. I have looked that how other trucks are wired and also looked up a few diagrams but that seem to have different answers to each. First the Owner swears this is a negative ground but I am not so sure. What does appear to be happening is they look to have set it up on 12v and were using jumper cables when starting. 

If anyone has some clarity I would be appreciative. I think it is supposed to be 

 

f1 - 2+

f2 - 1+

f3 - ST2 

f4 - 2-

ST1 - 1- 

But I am not certain as the diagrams conflict. What I am certain of is that when we hook it as it is, it tries to melt the last battery terminal we hook up. 

I get how series parallel works.   with one set connected neg to pos and the left over positive going to the truck and left over neg going to ground giving 24v

What I am not certain is how the switch is making the connection. 

It would seem to me it makes it across f1 to f3 but I need to learn a bit more apparently cause I am not certain on this. 

When I run 12v from a hot to the small post on the rear drivers side of the switch I get a "click" but that does not mean the switch has not failed and hence the goofy readings we get on the OHM meter. 

Thanks

 

 

[j hancock 13,666]

More diagrams in link to ponder.

https://www.bigmacktrucks.com/tutorials/article/70-wiring-schematic-for-series-parallel-switch/

 

[terry 528]

Looks like he has the second one in the photos,    terry

[mrsmackpaul 2,482]

When you hook the batteries up does the amp gauge show whether its charging or discharging 

If it shows its charging and the motor isnt running it would mean the polarity is back to front and if you have it hooked up for negitve ground its postive ground

 

Paul

[fuzzy buzzard 123]

Look at the B Model Registry on this site. There is a ton of info there including diagrams for SPS that are positive or negative ground.  

[phildirt 122]

This may be what you have already seen. The old voltage regulators were either negative or positive ground, but the more modern ones can be used with either.

If your series/ parallel switch has through bolts open it up and repair the burnt contacts.

There are two sets of contacts within the S/ P switch.