Is it possible, and is it advised? 2 reasons why I want to:

I'm losing .15 volts from the alternator terminal @ the fuse box to the battery. I think this is due to some sort of circuitry within the engine fuse box (not the cables) that cause this. Second, I want to replace the cable w/ something beefier w/ standard copper lugs for ease of maintenance, and the fuse box uses those non-standard 90 degree terminals.

I'm thinking that if its possible, I might need to add a jumper wire from the fuse box to the battery to fool the dash battery light. But that's just theory.

Thinking about it, say you turn on a winch or air compressor... the amps get pulled from the alternator, then goes through whatever wizardry is in the fuse box, to the battery, and finally to the winch or compressor. It seems a lot cleaner if it was a direct path from the alternator to the battery.

I also installed a 200 amp alternator today and want to support him in whatever he needs to do his job. The fuse box may not be designed to handle 200 amps (assuming this alt can actually put out 200)

 

That .15v is so insignificant you'd never really get that back. You're losing that through connectors and the cables themselves. If you're not charging at 14.4v or more, take a look at your alternator itself. May have some old worn brushes, windings or a bad voltage regulator.

 

there really should not be a voltage drop whatsoever between that short of a distance. You're getting 14.4v?? Can anyone else confirm that? With my old alternator and now my brand new one I see 14v max, idle or load.

 

I'm not at home, but last I tested my old alternator was getting 14.2v, new one is right on 14.4v. 0.15 volts is nothing. 14v is ok, but that could be your meter. When was it calibrated last? Also, 14v is technically ok for charging, it just won't charge as fast.

There's other variables which cause volt drop. Anything turned on in the truck at all? Any lights, radio etc? That will cause the voltage to start to drop, but typically not until you start to get close to the maximum output of the alternator.

 

The voltage will vary depending on battery type/size/brand very slightly. I was getting 14.6 with one battery and I get 13.8 with the one that was last in it.

Do NOT bypass the fuse box. If you do you're bypassing the big *** fuse in there and if it shorts out you'll burn your discovery to the ground. That .15v loss is nothing.

 

OK. Interesting. I have dual odyssey batteries so I'm sure they love to suck up the volts. I'll call it good for now. My only concern is that when I run the compressor at idle, volts drop to ~12.2v. Granted, it's a 50 amp load, but shouldn't the alternator be able to keep up with that and maintain ~14v? I put an amp meter on the alternator cable and it read ~55 amps, so thats pretty good (I'm guessing around 10-15 amps to run the truck, 50 amps for the compressors, gives me a net loss of ~10 amps... at idle)

side thought: how cool would it be to have an electrically wired switch to kick up the rpm's to ~2.5k and hold it? For winching and air compressors. The only solution I can think of is a linear actuated motor to tug on the throttle cable.

 

Doesn't surprise me s but to see that voltage drop.

Maybe a smaller pulley on the alternator?

What you're describing is essentially our cruise controlled system. Figure out a way to tap into that and you're golden.

 

You could run an MSD ignition with a 2 stage limiter, you should be able to wire that low speed (launch) limiter to a separate switch and relay.

You could also use a linear actuator or a solenoid to pull the throttle cable, but tuning the distance of the pull might be more difficult than running an aftermarket ignition.

 

Jeff,

I'm going to respectfully disagree with others here.

Because, you've changed the alternator to a higher output. Now, the cable should be based on that alternators amperage output. The cable supplied by the manufacturer is based on whatever type of alternator is installed at the factory. You've changed that. So, if you want to carry more amperage under certain types of load from your higher output alternator, like while using the winch, you need to up your cable diameter size. The capacity of amperage a cable can carry is based on diameter and length.

EDIT: And, you can add a 200 amp circuit breaker inline if you like. There are plenty of different models available...l like the resetable ones.

As far as rpm's go...

You could rig up a locking throttle cable, they are inexpensive and found at any lawn mower supply store or online. You'd just have to fabricate a bracket at the throttle plate housing to accommodate the additional cable.

We use to have this type of setup on all of our wreckers, back in the day. I like the locking throttle cables where you twist a **** to set them, then hit the red button on the end to immediately release. Pretty simple installation, make a bracket for inside the cab, mount cable, run the cable through the firewall and attach to whatever bracket you come up with at throttle housing/plate. They usually run about 30/60 bucks for a nice cable. Some of the cheaper locking cables just pull out and twist to lock, but if something goes wrong and you want to release them quickly...it can be a bit more of a struggle releasing the twist lock, button...you just tap it with your hand...and you're back to idle.

Brian.

 

It helps to read this:

http://www.carparts.com/classroom/charging.htm

The problem is that whatever alternator used it entirely depends on the losses and draw of the battery(ies) being charged plus other consumption, clock, alarm system, ECU's etc, etc and is controlled by the main power fuse of the system whatever that is in size. The voltage and amperage is regulated to avoid 'cooking' the battery and system. The charging system is designed to only draw down what is necessary for maintaining the loads be it battery charging, clocks, alarms, ECU's etc.