[Vwdiesel] Re: vwdiesel digest, Vol 1 #563 - 5 msgs

[kayser at sympatico.ca]

Sandy el all:

> Most of the diesel pickups, like the chevy suburban, the ford powerstroke,
> etc, use dual batteries, and they just connect them in parallel.

Sandy:

Close but not quite.  I once examined Graham's oldsmadozer very carefully and I found equal lengths of charging cable from the alternator and equal lengths of cable from the two batteries to the Starting Motor terminal.  This included some wire folded back on itself in the harness.  Only one other time did I find this in a dual battery diesel in a Caddilac and after carefully looking I found the same type of setup.  Later I was to find out that many GM alternators for heavy duty service, two battery type of service, have .3 to .5 volt extra voltage for floating the batteries.

Also Sandy you might remember when I had  57 Volvo marine units to look after, we found a little screw adjustment internal to the alternator.  This boosted the output voltage about .6 or so volts, for use when using a diode isolator block.  Of course we found this set the wrong way on 57 alternators feeding up to three big batteries, you have to remember how much I love Volvo products....  I wont bring up here about the failure mode you found in the intercell battery tab welding, I think VARTA is still in the battery business......

Larry
VA3LK