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I'm a long time lurker on here...I'm interested in swapping in a GM alternator. I have already bought the bracket, alternator, and pigtail to splice. My question is, how do you keep the stock battery gauge working?
I read a long time ago about the use of a 50 ohm resistor, but can't find it anymore. I don't care wether to "1-wire" or "3-wire" it, as long as it charges and the gauge works.
I've searched and searched, but haven't read anything definitive on how to keep the gauge working. Thanks!
Last edited by MikeNasty; Apr 27, 2015 at 01:08 PM.
Does a '85 4runner have a "battery gauge"? I (1994 pickup) have an voltmeter and an "alt" lamp. Both are useful/necessary to monitor the electrical system, but neither is a "battery gauge."
The "resistor" that you may be referring to allows you to use an "alt" light with an obsolete "1-wire" alternator, and keep the alternator working (to the extent it works at all) if the bulb burns out.
But the cited article may help straighten it all out for you.
Last edited by scope103; Apr 27, 2015 at 02:38 PM.
From the EWD from your vehicle find the wire that feeds the voltmeter then that can be connected any place you want I like to hook direct to the battery .
I guess it might be called a battery gauge when the alternator is not spinning .
From the EWD from your vehicle find the wire that feeds the voltmeter ...
The voltmeter is built-in to the combination meter, and measures the voltage on the "bus" in the meter itself. Which is usually what you want; if you have a problem with the wiring that causes a big voltage drop, it doesn't do you a lot of good to have a meter telling you there is "no problem." More importantly, if MikeNasty is just replacing his alternator, he doesn't have to do anything to the voltmeter to get it to work the "factory" way once he gets the alternator hooked up.
MikeNasty's problem is trying to hook up an alternator that doesn't have the connections needed by his truck. The article I cited does a pretty good job (I think) of going through his options.
the first step in charging system troubleshooting 101 is to put a voltmeter across the battery terminals, and see if there is higher voltage present, than what the voltage of the battery is with the engine not running... and that's exactly what wyoming9 was suggesting.
i guess that we'd have to look at the schematics and see where that "bus" hooks up... but generally when there is a big voltage drop, there is going to be a lot of heat being generated, so things will be burning long before you see the meter on the dash, or in a properly designed system, fuses will have already blown... so i don't see much advantage to hooking up the factory voltmeter anywhere other than directly across the battery.
i have that same 47294 from powermaster, it's been good for me so far, but i still question the validity of my install... i guess that it's human nature to think that we have to do a bunch of rewiring to get this to work.
in my case, i hooked up the fat wire that came with the alternator, directly to the battery... 1)i sleeved it, but didn't fuse it, and i probably should have, 2)i don't yet have any external winch or welder hooked up, so why do i think that i need the additional current-carrying capacity of that fat wire, back to the battery?
...in my case, i hooked up the fat wire that came with the alternator, directly to the battery... 1)i sleeved it, but didn't fuse it, and i probably should have, 2)i don't yet have any external winch or welder hooked up, so why do i think that i need the additional current-carrying capacity of that fat wire, back to the battery?
A dead battery is almost a dead short; your new 175 amp alternator would end up trying to drive a lot more than 175 amps unless the fuse blew. An accidental slip during battery jumping would make a real dead short. The purpose of the fuse is to protect the wire from the unexpected; it doesn't matter whether you have a winch or welder (those would be design loads, which should never blow a fuse).
that makes sense, a winch could easily pull hundreds of amps, it would be difficult to fuse... my bronco goweld is rated at 24v/200 amps.
i gotta get a fuse going with that direct line from the alternator to the battery... it looks like anl type fuses are the only form factor that handles 150+ amps.
i have the trail gear bracket, it's bolt-in, but i modded it heavily... had to cut off nearly half of the fork length, because it was fouling the hydro-assist, replaced the long main bolt with a metric bolt, because it fit the hole much better, and welded the factory toyota alternator mount brace onto the trail gear brace(belt tension fork piece), which added an xtra bolt to mount it to the block... much more stable.
Scope thanks for your first post that link has loads of info and I think I'll eventually change my wiring set up. With additions of electrical accessories my battery post look like the terminal buss. Hadn't seen that the cs130 was more or less a disposable alternator. Really don't know why anyone would run a one wide set up in our trucks, but if anyone has it is your rig and a free country so rock on.
Apr 27, 2015 | 01:06 PM
