12/24v circuit Relays

Hello.

I have a ford 4cyl diesel 192cid. I burnt the starter out of it this past sommer, unrepairable and nla. I cobled one togather that works well in the sommer, but not in the winter (wont spin fast enough), So I am going to hit the starter with 24v, using relays

Problem.

How to do this and protect the remaining 12v circuit?. ie injector punp sol. alt. elec. fuel pump. and still charge at 12v?

I have tried all the tricks, thinner oil ,water heaters ,block heaters, eather.

I have some ideas but would like some input before I blow everyting up

Thanks for any help. French Town

It'd be simpler just to replace the starter, upgrade the wiring to something much bigger (grounds too), and install the largest CCA battery that'd fit.

Geepherder.

no room for larger starter, have an 8D batt.  using 2 ea. 00 cable +& - AS short as routing will permit.

Thanks for the input. Frenchtown.

       hotwaterwizard,

              Thanks for the input, this is the circuit I use now, but it will not charge both batt. my thinking is, use two dpdt relays to switch between a series and parallel circuit  while maintaining 12v to the rest of the system.

              My concern is spiking and/or welding of the contacts. also thinking of how to use diodes to help. but were do you find them rated at 200amps or more?.

                                            Thanks again,  Frenchtown.

Okay,

I get what you're saying, how about something like this?  https://cgi.ebay.com/dll?ViewItem&category=50552&item=5740485166&rd=1

Yeah, I'd definitely diode isolate.  You should be able to pickup some 6a diodes at your local electronics store, and see if that works.

There is a truck component (multi-contact rotary relay) that switches two batteries from series to parallel (24:12v or 48:24 etc) I recall they cost about $75 new -never used one but looked hard at it for my old RV - I think it was for starting and drew too much current to keep energized more than a minute or so.

One of the old closed topics on battery isolators have several references to the 0.7v drop in a battery isolator passing 200 amps generating 28VA (watts) of heat - no one ever corrected the post so here goes 0.7A x 200A =140watts  (I x  E =watts)  28 watts wouldn't even get the fins very warm-

I need wiring diagram (colors and schematic) for a 2005 Chev Silverado 1500 Extended cab - no books out yet - anyone know of a link that has accurate information except Alldata (subscription)