2 battery BJ70 starter only has 12V?

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Jan 7, 2016
Everett, WA
I have a Canada spec BJ70 with 3B 24V start/12V everything else.

I'm only getting 12V to the starter.

Does anyone know if there's a switch that controls power to the starter? Like a series/parallel switch? I know turbo diesel 80 series use them.

Or perhaps my batteries are connected incorrectly? Currently each battery has its own ground at the battery tray, and on the engine block, and the positive wire from the secondary battery is attached to the positive terminal on the primary battery. Should the power wire from the secondary battery also be attached at the starter post? That would put 24v at the starter, and the small signal wire gets 12v, right? This makes sense in my head but then the second battery wouldn't recharge. So that doesn't work.

I was thinking my starter itself was the issue, but after pulling it this afternoon, and checking out the contacts, they looked fine, so I decided to check power at the big power wire and sure enough, only seeing 12V there.
The CDM BJ70 are either full 12v (1985) or full 24v (1986 - 1987).

So, your battery should be, either, in parallel (1985) or in serie (1986 - 1987).

The way you describe how your battery are wire indicated they are in parallel.

The correct way to wire 2 battery in serie is :

Ground the first battery, plug the + terminal to the - terminal of the second battery, then you will get 24v from the + terminal of the second battery.

BEFORE YOU TRY TO PLUG YOUR BATTERY IN SERIE, make sure you have a 24v vehicule ! You don't want to fry your electric device !

Remember the CDM BJ70 did not have 12/24v system as some diesel 80 serie have.

If you have a 12v BJ70, you will need a 12v starter
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I see. I was wrong thinking the dual battery meant 24v start. Guess I'll continue looking into my starter being the issue. Thanks!

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