Low alternator charge at idle

[1 Wild R/T]

Is there any special modifications required to get the LED lights to work with our cars? I seem to recall when LED headlights first came out that some additional wiring upgrades were required.

LED Turn signals require LED compatible flasher units, the normal flashers rely of current to heat a thermal switch AKA a bi-metallic strip to make & break contact... LED's draw significantly less power so the lights never flash... Also LED are polarity specific and usually on a Mopar the hazard flashers wires at the flasher need to be reversed.... Headlights should just be a drop in deal...

 

[Sinitro]

Is there any special modifications required to get the LED lights to work with our cars? I seem to recall when LED headlights first came out that some additional wiring upgrades were required.

Nope... LED headlights just plug into the OE connectors, for the other bulbs like brake lights, turn signals the flasher unit should be chnaged to an electronic one.
A major advantage of LED headlights is they draw much lower current so they work just fine with OE wiring provided it is in good condition.
Just my $0.02...

 

[70ChargerRT]

Nope... LED headlights just plug into the OE connectors, for the other bulbs like brake lights, turn signals the flasher unit should be chnaged to an electronic one.
A major advantage of LED headlights is they draw much lower current so they work just fine with OE wiring provided it is in good condition.
Just my $0.02...

I did all this back in 17 and im only interested in the 4 lights on low conversion which I just figured out. Depending on your charging system it’s only going to cost you around 3 amps total to go to a 40 amp bulb and they are way brighter. Octane already has a 25w bulb which would be good for factory wired cars because they’ll only consume around 8 amps total to the Holleys 10 amps that could very a tad. 160 amp 1 wire alt maybe having me using even less AMPs. I’ll have to check it out one day.

 

[OneWheelPeel]

I switched my cars over to the Toyota 4 Runner Denso style internally regulated alternators. I did it for a different reason however. The high output (15-15.3 volts) that all of the new electronic voltage regulators for 1969 and older put out. I did buy the bracket kits from AR Engineering, but some guys are just adding a couple different spacers to the OEM setup and getting it to work. Night and day difference in how these Denso's charge. Even at 800 rpm, they are putting out the correct full voltage. I had the Denso's tested before installing, and they actually put out more than 70 amps. I couldn't be happier with the upgrade.

Do you recall which year and optioned 4 Runner the alt would have come on?

EDIT Nevermind found it on google etc. Toyota 4Runner (1985 to 1991 with L4 engine)

 

[OneWheelPeel]

So let me know if I am stomping on this thread and should start my own, but same topic so seemed appropriate.
Today I measured my voltage at the battery and at the alt. With the car idling over above idle the battery never gets above 12.8, measured at the battery posts. Measured at the alt I see 14+. The car has not run for days if that figures into state of charge.

So real simple (and maybe I get an answer soon enough I can do this today before the work week starts) if I don't care about originality or the amp gauge being accurate in the dash (I have a sep voltage gauge anyway) can I run that output directly to the + of the battery or its starter relay post, leave everything else alone and not run into problems?

 

[1 Wild R/T]

yes You are supposed to use a fusible link. I didn't.. Instead I sleeved the 8 Ga wire with a 5/16 fuel line & paid attention to how I routed the wire making sure there was no sharp edges or hot metal to damage the wire...

 

[OneWheelPeel]

yes You are supposed to use a fusible link. I didn't.. Instead I sleeved the 8 Ga wire with a 5/16 fuel line & paid attention to how I routed the wire making sure there was no sharp edges or hot metal to damage the wire...

Thanks, I'll probably copy that. I was pretty sure I read it was ok to do that on this forum but I've been trying to cram so much of the Mopar specifics that its a bit like drinking from a firehose.

 

[Kern Dog]

Sorry, guys. I started this thread and like I often do, I got distracted with other things.

I got tied up in some bodywork and paint for my truck, then resumed work on the deck at the back of my house.
With my low voltage issue, I have not tested it at the alternator or battery directly. I simply read the gauge on the dash. I do like the idea of testing the alternator and battery though so I will try to do that before and after the alternator swap.

 

[OneWheelPeel]

Nice truck!

 

[72RoadrunnerGTX]

.... can I run that output directly to the + of the battery or its starter relay post, leave everything else alone and not run into problems?

That will expose all factory unfused wiring to the full current potential of your battery in the event of a short. Ohm’s law as applied to parallel circuits. See post 32.

 

[1 Wild R/T]

That will expose all factory unfused wiring to the full current potential of your battery in the event of a short. Ohm’s law as applied to parallel circuits. See post 32.

So, the starter circuit... Cause everything else is fused

 

[72RoadrunnerGTX]

So, the starter circuit... Cause everything else is fused

Starter circuit? Not following. The described by-pass, a direct wire run from the alternator output stud to the battery by-passes the stock fusible link. Even with a fusible link on the so-called “shunt wire” it still raises the circuit protection beyond anything the stock 12ga wiring can handle in the event of a short. Again, referring to post #32 of this thread.

 

[1 Wild R/T]

Starter circuit? Not following. The described by-pass, a direct wire run from the alternator output stud to the battery by-passes the stock fusible link. Even with a fusible link on the so-called “shunt wire” it still raises the circuit protection beyond anything the stock 12ga wiring can handle in the event of a short. Again, referring to post #32 of this thread.

Everything but the starter is fused... Okay, the wires between the battery & the fuse box aren't protected... I'll roll the dice...

 

[72RoadrunnerGTX]

Okay, the wires between the battery & the fuse box aren't protected... I'll roll the dice...

as well as the ignition switch, headlight switch, ammeter, and quite a bit of 12ga dash harness wiring that depend on that fusible link for protection will now be exposed to the full 150-200 amps of battery potential via that "shunt wire" by-pass, not a bet I'm willing to take.

 

[OneWheelPeel]

Well I ran out of weekend time so I never did anything else to the car, but after reading a few threads and posts including some from 72RoadRunnerGTX I went outside for a quick check after work and was a little surprised by what I found.
Started'er up and the amp gauge moves in the charge side which I expected, grab my gauge and go under hood to first verify what I mentioned before, about 12.5v at the batt, 14+v at the alt, no surprise yet.
Then measured at the fuse panel and see 14+v, even see 14+ at the crusty old dome light socket that has no bulb, both nice mild surprises.
Then crawled under the dash to measure voltage behind the amp gauge, alt side had 14+ but the batt side had 12+. This is where I am surprised, is it normal for an amp gauge to eat a couple of volts? I was always under the impression they had a minimal effect on the voltage passing through them.

 

[72RoadrunnerGTX]

I was always under the impression they had a minimal effect on the voltage passing through them.

With good/tight ammeter connections there should be very little to no voltage drop across the ammeter terminals. Verify by connecting your VOM leads directly at the terminals, one on each side. If confirmed, check that the terminal nuts are tight, and the insulators are undamaged. Abused or prolonged loose stud nuts can lead to resistance build-up at the internal stud head to bus contact surface. The resulting heat can damage the insulators further. Close inspection of the ammeter and its terminals is warranted.

 

[OneWheelPeel]

Thanks for the confirmation, I'll probably dig into it on Saturday. I did check that they are tight but I just looked thru random pics I took with my phone blindly stuck under the dash and the insulator here does not look too good. Like one good bump and the post could hit the gauge housing.

 

[72RoadrunnerGTX]

Yikes, that’s a problem. Pretty clear that one stud has suffered some heat damage previously, the end of that outer stock insulator is missing, likely the inner one is damaged as well. I would plan to pull the ammeter, solder the stud heads to the bus, replace both insulators.

 

[OneWheelPeel]

Thanks for that link to the insulator. I never really leaned strongly pro or anti amp gauge, but at least in the short term I guess I will jump those wires together to keep things driveable with a little less stress. The whole gauge cluster is very rough and the speedo is damaged so I either replace with a nicer used one or just go all after market gauges and make my own bezel (which would be fun for me). I've already gone autometer with fuel/volt and temp. I basically just relied on the stock cluster for the oil pressure idiot light and the turn signal indicator in the limited driving I've done with it.

 

[72RoadrunnerGTX]

Agreed, if no immediate plans to restore/replace the factory cluster/ammeter, at a minimum connect the two ammeter wires together right away, insolate appropriately.