J.C. Denton

iTrader: (1)

Hi guys,

short question: I am upgrading to a CS144 alternator and a 10ga charging wire from the "Bat" Terminal.
I have a V6, so my alt sits right above my starter. Can I run the cable from the alt to the starter or do I have to run it from alt to positiv battery terminal? Does the battery work like some buffer or something? Will anything be toasted? I can't imagine if it is a problem, but I thougt I'd better ask you pro's...
I wonder why GM routed the original wire to the little junction block and from there to the battery... A short connection to the starter would be more useful I guess...

Thanks!

JunJun

The alternator produces no electricity when the starter runs, so I dont think theres any point in connecting the alternator and the starter.

sofakingdom

iTrader: (1)

There's no reason you can't hook it there.

Either end of the big red battery cable is fine. For all practical purposes (except of course, the conditions during cranking), both ends of the cable are electrically identical.

GM's reasoning, same as any other mass producer of anything, sometimes has more to do with manufacturability and that sort of thing, than it does with what we think of as "function". Some of the decisions that are made for that type of reason are completely inscrutable from outside the factory.

Use a fusible link. Newer trucks for example, with a somewhat similar arrangement, use about a 15" piece of 5.5mm fusible link wire (around 13 ga) as the alt output, and it goes from the alt to a junction in the middle of the big red cable halfway between the batt and starter. DO NOT hook up the alt without a fusible link, as REAL BAD things happen to cars when electrical faults occur and there's no circuit protection to clear them... like, they burn to the ground.

J.C. Denton

iTrader: (1)

Thank you sofakingdom! Thats what I needed.
What size of fusible link should I use? 150 Amps?

Thanks!

JunJun

sofakingdom, this might be a stupid question, but whats the point of connecting alt and starter? what difference does it make?

sofakingdom

iTrader: (1)

One way or another, the alt has to be connected to the batt.

The big red batt cable connects to the batt. Both ends of it are, for all practical purposes other than starting, the same electrical point; its resistance is totally negligible at the small (relative to that cable's size) current produced by the alt. The alt does not care which end of that cable it's hooked to, juice will flow where it needs to go, regardless of which end is used.

The OP wants to hook the alt to the far end of the cable, from the batt's point of view, instead of the near end. There's no reason that won't work or that it's wrong or anything of the kind.

Tibo

iTrader: (15)

Best way to wire it is to a distribution block from the alternator, that way the alternator is sensing the load requirements of the system rather than the charge of the battery. Using the battery as a distribution point, while extremely common, presents a higher likelihood of shortened battery life due to the alternator not wanting to put out the necessary amperage to power the system until the battery has lost its surface charge. If you're upgrading the charging wire, skip the 10 gauge and go to at least 4 gauge. Then don't forget to use four gauge on the grounds to the frame and engine .