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Discussion Starter #1 (Edited)
Headlight Issues

So yesterday after work I drove the Beast a couple hours down to where Mrs. Bear is spending the weekend dog-sitting for her step-mom. After it got dark I was having the devil of a time seeing (yeah, I'm olde and that's a factor, but....). I checked the headlights after I arrived and on low beam they looked dim to me even though both sides were on, and further when I put them on high beam it went into cyclops mode with the drivers side lights both on but only one passenger side bulb on but super dim. I've also noticed my high beam indicator is on vacation.

So before I start tearing into things --- does this sound like a bad dimmer switch (it's original), headlight wiring harness (it's new), maybe a bad ground? I don't have my wiring diagrams with me...

Update: Well, it aint the dimmer - doggone it. Guess it's time to get the meter out (luckily I brought it) and start chasing.

Bear
 

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Discussion Starter #2
Well duh!!! I just pulled all 4 headlights --- I'm only getting around 8 volts to each one. Joy - so I decided to check it with the engine running, which turned out to be a problem because it wouldn't start. Eek... so I jumped it off Mrs. Bear's car, then put the meter across the battery to test the voltage regulator. Sure enough, only 13.5 volts at charge. Dangit... this will make the 3rd regulator I've put on this thing since November.

I wonder if heat in the engine compartment is killing them? I've been using the solid state ones because I haven't been able to find a quality points-type regulator.

Bear
 

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Bear, Did more volts cure the problem??? It sounds like the infamous ground issue to me...Although it is kiiiinnnnda the same thing...what goes out (+)...must come back(-)....Eric:willy:
 

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I replaced the regulator, had the alternator and battery tested and both tested good. However, driving the car home last night, running it for about 30 minutes with the headlights on was enough to drain the battery to the point where it wouldn't start and had to be jumped. I'm suspecting that even though the alternator tested good (at Autozone) it's not able to keep up with demand at full load, running the headlights.

Bear
 

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Yeah, stuff that's "beyond stock" include twin Spal electric cooling fans and the HEI. According to Spal's web site, the fans alone can pull 40 amps, add 5 for the HEI, and I'm nearing the capacity of the alternator right there. I've been researching the past few days, and I'm leaning heavily towards replacing the factory alternator with a Delco CS144 style unit. That'll give me 140 amps, and I hear they also produce more output at low rpm. The wiring conversion to hook it up and eliminate the VR while retaining the charge warning light doesn't look too bad.

Bear
 

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Discussion Starter #11 (Edited)
:eek: I think the factory alt is around 50-60 amps.....me thinks you are suckin' harder than the ol' girl can put out!!
Yeah, I thought I had it solved yesterday. I got a CS144 frame unit (spec'ed for a 96 Buick Roadmaster wagon of all things), that was rated at 140 amps. I researched it and found instructions on how to convert my wiring harness to eliminate the voltage regulator, connect this one up, and retain the function of my charge warning light. I swapped pulleys on the CS144 and got it mounted, checked belt alignment and sure enough it needed to move rearward about 3/8". I could have accomplished that by shaving off the back side of the wide mounting boss on the alternator frame and shimming up the front side - except for the fact that there was only about 1/16" between the back of the alternator and the front of the drivers side cylinder head making it impossible to move it back any more than that without completely re-doing the mounting bracket to move the alternator somewhere else entirely. :mad:

So, back it went for a refund and the hunt started over.

A CS130 frame unit is smaller than the CS144 by quite a bit, or so it appears in the photos of them. I found some CS130's on NAPA's web site that are rated at 120 amps ---- but of course they're all "special order" and none of the stores nor warehouses anywhere in the Dallas area have them. :( However, I did locate a reman CS130 at a local O'Reilly store that's rated at 105 amps - which is almost double the rating of my factory 10dn. This CS130 is spec'ed for an 88 Pontiac Safari Wagon. The store put it on hold for me, so I'm going to try that one next.

Hoping for some luck ----- "if it was easy, it'd be a chevy". :D

Bear

UPDATE: Well, the CS130 is going to fit in the bracket and it looks like the pulley is going to line up correctly - that is, as long as I use the pulley that came on it instead of the "deep groove" pulley I already had that I was planning to use. I'm halfway home. :cheers

Now to get it wired up and see if everything works right.

UPDATE to the UPDATE: It's all in and working, including the charge indicator light :cheers It even looks "relatively stock", and all the lights are nice and bright now. Imagine that... I wonder what "challenge" this car is going to throw at me next? :confused

 

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I was able to find a one wire 100amp alt from a local alt shop. Cost only $110 and hasn't given my any problems with the additional amps I'm pulling from the electric taurus fan and amp I have powering my speakers.
 

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Hi Bear. Can you share where you got the instructions to convert to a one wire alternator? I tried and the warning light is on and dim and I can't figure out why....
 

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Sounds like a ground issue to me also. I put 1 wire alternators on my cars, $50, autozone, and lifetime warranty. You can fake the spare wires up there if you want. Ditch the external alternator and call it good. 1 wire from Alt to battery is all you need.
I was able to find a one wire 100amp alt from a local alt shop. Cost only $110 and hasn't given my any problems with the additional amps I'm pulling from the electric taurus fan and amp I have powering my speakers.
This is what I did. Seems my car had already been done this way tho. I ended up needing a new alt after I got my new engine in.

Why go back with that old outdated regulator crap anyways? :lol:
 

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the ALT light stays on because the external regulator is no longer present to "tell it to turn off" ...the wiring is a little different with a single wire Alternator...if you go to Mad wiring's web site, I beleive it is explained there...Eric
 

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Hi Bear. Can you share where you got the instructions to convert to a one wire alternator? I tried and the warning light is on and dim and I can't figure out why....
It depends on which alternator you got - is it a 10si, 12si, CS130, CS140?

What I did was to disconnect the plug from the voltage regulator, put a jumper wire on the plug connecting terminals 2 and 4 (4 I believe goes to the light in the instrument panel, 2 goes to the light connection on the alternator connector), then connecting the light wire in the original alternator connector to the light terminal on the alternator.

Once you know which family alternator you have, if you Google search for that alternator type plus "wiring conversion" you should find lots of references on how to do it.

Bear
 
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