Alternator Troubles

[tigger]

Hey guys. Long story short, my car is a 30 year old P.O.S. I've rigged an internally regulated alternator into it, which has solved the problem of my car blowing up batteries. But it's not maintaining the batteries charge; it's slowly falling. I've been told that rigging up a ~500 ohm resistor between the voltmeter terminals will get the alternator to crank out a little more amperage. I may have a smaller radius pulley I use for the alternator, but I'm going to try the resistor bit first. Any thoughts?

 

[Quiky]

Get a battery maintainer/charger that you can plug in when you park it at home.. easiest solution.

http://www.batterymart.com/p-del-021-0128.html

 

[Spectre]

Check the alternator's diode pack and make sure you didn't accidentally wire the old regulator back in.

 

[tigger]

Get a battery maintainer/charger that you can plug in when you park it at home.. easiest solution.

http://www.batterymart.com/p-del-021-0128.html

Two things; I don't have a garage and that's just a hassle. I've already got a charger, but I'd like to permanently fix the problem.

Check the alternator's diode pack and make sure you didn't accidentally wire the old regulator back in.

Is the diode pack under that black plastic cover on the back (Ford 2G alternator)? The old voltage regulator and it's wiring harness are in the trunk, so no chance of them being wired in.

I still haven't had a chance to wire that resistor up, I got dragged into working on my Yamaha.

 

[Spectre]

It's probably under that, but you should just dismount the alternator and take it to Autozone to have it tested. You should also test for current draw when the car is off.

Also, don't wire up that resistor.

You know what I'm thinking about someone having to work on their Yamaha, right?

 

[tigger]

It's probably under that, but you should just dismount the alternator and take it to Autozone to have it tested. You should also test for current draw when the car is off.

Also, don't wire up that resistor.

You know what I'm thinking about someone having to work on their Yamaha, right?

I'm fairly certain that the alternator is good; it came from a running Ford pickup. There doesn't seem to be any current draw with the ignition off, but I'll stick a multimeter on it.

Hey, the Yamaha's reliable ! I'm putting in some new oil seals on the fork sliders.

 

[Nabster]

Whats wrong with the old alt and voltage regulator setup? Voltage regulators are cheap and simple to test and replace, whereas those internally regulated alts can be expensive and a hassle to troubleshoot.

 

[Spectre]

You can get another internally regulated alternator from a junkyard for $20. Not so easy to get the old tech external ones. Also, the old ones don't produce enough power for modern driving scenarios, especially if you upgrade the lighting so you can actually SEE the road.

 

[tigger]

Whats wrong with the old alt and voltage regulator setup? Voltage regulators are cheap and simple to test and replace, whereas those internally regulated alts can be expensive and a hassle to troubleshoot.

Sure voltage regulators are cheap; $8-10 a pop. But when you have to buy a new one every couple months, it adds up. Now if only I could get this 2G alternator to actually charge the battery, I'd be in business :lol:.

School just started up again so I still haven't had the time to properly troubleshoot the Fairmont. Thanks for the help so far though. I did find that it's drawing current with the ignition off (it sat 3 days then would hardly start), now I just have to figure out which hacked up bit of the wiring harness is the problem.

 

[Nabster]

Sure voltage regulators are cheap; $8-10 a pop. But when you have to buy a new one every couple months, it adds up. Now if only I could get this 2G alternator to actually charge the battery, I'd be in business :lol:.

School just started up again so I still haven't had the time to properly troubleshoot the Fairmont. Thanks for the help so far though. I did find that it's drawing current with the ignition off (it sat 3 days then would hardly start), now I just have to figure out which hacked up bit of the wiring harness is the problem.

If you're having to replace voltage regulators that often you have other problems you need to find and fix. Or you need to dish out an extra $20-30 for a much better (read: not built in china) unit- Napa offers one with a lifetime warranty for $30-50.

As far as finding the draw on the battery, on the old mustangs you just pull one fuse at a time until the draw stops, once you've got the right fuse, that makes finding the problem easier as you know where to look. If none of the fuses stop it, the draw is between the battery and the fuse box. It's probably just an exposed wire contacting somewhere that grounds and causes a draw, hopefully anyway.

 

[ruuman]

back in my days of POS cars I had a couple with terrible battery discharge problems. My easy soloution was to just wire a battery isolator like this:

then just used that as my ignition key too, not that secure but the car's were crap so I didn't care or ever lock it

 

[tigger]

As far as finding the draw on the battery, on the old mustangs you just pull one fuse at a time until the draw stops ...

That's pretty handy. Tracking that current draw down will be a secondary consideration though; I need to get the alternator working first. I've got another 2G that I'll swap the diode pack from and then break out the multimeter. Damnit, it's going to be ... Thursday morning before I can even look at it.

but the car's were crap so I didn't care or ever lock it

:lol: I've had this car for 6 months and I still don't have a door key.

 

[tigger]

Alright. Just had the alternator tested and it's working great. And I think I've got my voltage drain tracked down to the headlight circuit. Now I just need to work out getting it to charge.


Edit: Got it. For the first time in something like 2 months my batteries not about to explode or die! Of course I went ahead and screwed some other stuff up, but it's nice to see it charging properly again.