B To Alternator

[Red Horse]

Guys, I want to convert my B to an alternator and get rid of the series parallel switch. I'm swapping cabs so all of the current wiring is junk. I assume if I buy a harness from say Top-O Hill or any other supplier, I will be getting a lot of stuff I don't need given the conversion to an alternator.

Any thoughts? I have to believe many of you have "been there-done that"!

[vanscottbuilders]

If you call Top-O-Hill, they will ask you how you want the harness

set up.

I have a new one from them for a B model that I am using a single

big battery, no series parallel switch, and a single wire alternator in.

They set it up just the way I wanted it.

Barry at Watt's Mack also has harnesses made up for them that they sell.

Paul Van Scott

[Freightrain]

Well, when I switched mine over, I ran the alt wire direct to the batteries(int. regulator), so no added wires needed anywhere and the stock harness was left alone.

I installed the starter solenoid under the passenger seat(basically next to where s/p switch was), so I could still use the original starter button wiring. I plated over the opening in the floor as I put two Bostrom seats in the truck. I ran all new wiring from batteries to new 12v starter. The old wiring from the s/p switch all goes away basically when you unwire it from the batteries. Only thing left is starter button wiring which I re-used.

It was all pretty simple, no cutting wires, no adding a bunch of needless junk. Works perfect.

[Red Horse]

Paul, Larry,

Thanks for the responses. Will look at both options.

Bob

[vanscottbuilders]

Bob,

Actually my approach is exactly the same as Larry's.

He just did a much better job of explaining himself.

I am also replacing the harness with new. But after talking

to Top-O-Hill, I was told that by running the internally

regulated alternator wire to the batteries, the harness

essentially is unchanged.

I did the same thing Larry did with the starter solenoid for the same reason,

and I left the old series parallel switch box in place, with a new floor panel in it,

and a hinged lid, to mount my new maxi brake and trailer brake buttons in.

I've left the original air switches in the dash for an original appearance.

Have Fun!

Paul Van Scott

[vanscottbuilders]

Bob,

Also don't forget that if you do this - the starter needs to be

adapted for 12v use, rather than the existing 24v, and the entire system

needs to be reviewed for negative grounding, rather than the old positive ground.

Paul VS

[Packer]

And don't forget that if going from positive to negative ground, you

must swap the wires on the amp gage for it to read correctly.

Packer

[Freightrain]

Yes, the starter needs changed to 12v, though the pos/neg ground is not an issue actually with the starter. They spin the same no matter what ground is(that is what I was told by starter people). It's good to change to NEG ground though so you can add accy's and have them work properly.

I removed the AMP guage and replaced with Voltmeter(old style S/W to match existing), but just swapping the leads on the AMP meter will then make it work correctly.

[CML Service]

For simpicity when I put an alt in my B model I used a Leece Neville because thier terminals are isolated and I just wired it for pos ground. This was a long time ago when I was still running a series parallel switch. I even left it pos ground when I changed to a 12 volt starter the starter doesn't care.

Chuck

[Red Horse]

Hey guys, thanks again