Alternateor/Voltage questions

[akcrogers]

So, as I expected, when all of my lights are on there is a noticibable draw on the voltage meter. My X has always maintained a steady 1/2 to 3/4 on the voltometer, and with the lights all on it sits between 1/4 and 1/2. This is still within the "normal" zone, but is it okay? How can I tell if it is draining the battery?

I expected this to happen, and am planning to upgrade the alternator soon, but I'm just curious in the meantime, so I don't get stranded somewhere...
thanks

 

[jimbo74]

not sure if this works on a newer vehcile... but the older detroit gearheads use to test it by disconnecting the ground cable while the truck was running and see if it would die.... if it dieed the alt was screwed if it didnt it was fine.....

 

[mrboyle]

Originally posted by jimabena74
not sure if this works on a newer vehcile... but the older detroit gearheads use to test it by disconnecting the ground cable while the truck was running and see if it would die.... if it dieed the alt was screwed if it didnt it was fine.....

Sorry, that won't work with on newer vehicles (anything with electronic ignition), since the electronics can not function without a ground.

As for your charging question, when you sya "all" your lights on, does that include the PIAA's? If so this is normal, because your alternator can not handle the extra load at idle. Try running the RPM's up to 1500 and see where the needle is on the volt guage. If it reads where it use to your fine, if it is still low I wouldn,t recomend running all your lights until you upgrade the alternator.

 

[ScottyM]

I have a 1994 "X" and when it idles the voltage meter almost drops past the "N" on the volt meter gague. The lights dim and the blower motor slows down a lot. Also when I shift it from drive to reverse or reverse to drive it seems to want to almost stall. However when I give it gas the voltage meter goes back up to about the "M". Is it time for me to get a new alternator?

 

[BTRs X]

My truck is doing the sam thing ScottyM's is. It has a brand new battery and at stop lights the gauge drops way down and the lights dim. Also when I shift gears on the automatic, the truck seems to want to stall. Whats wrong?

 

[Robb]

Both you guys need to get your hands on a voltmeter and check the voltage at the battery with the engine running. If you can't get your hands on one, go to Autozone (or a number of other places that check this stuff out for free) and have it tested. It is close to impossible to diagnose what is really happening without some accurate voltage readings.

Robb

 

[BTRs X]

what should the voltage be at the battery? 14.7v?

 

[MattHarrell]

Well, my truck is apparently working differently then everyone elses. At idle with all my lights on (headlights and PIAA 1500s) along with my ham radio (since it has a voltmeter on it) then I get 14.1V - maybe down to 13.7V. When I drive I've seen it go up to 14.7V when I've drained the battery down but it usually hangs out around the low 14's.

The gauge on the truck is really weird. Apparently just right of the middle is around 14V but 2/3 or farther along is only about 14.7V. Very limited range. I did find it useful to determine when my regulator was going out last year, though, since the erratic jumping all over was a good sign something was wrong.

 

[Robb]

At (no load) idle, Explorer alternators should produce ~14.5volts.

Robb

 

[olemech]

alternator

don't take neg, cable loose and take it off battery can hurt the computer. best way to check alternator is to test it with volt meter, should be 14volts with ever thing off.

 

[ajevenson]

I dont put any faith in any of the Explorer guages. My alt runs at "R" in the summer and at "18" during the winter, yet reads 14.2-14.7 at idle. Yea it bounces around a bit when shifting gears and turning lights on/off, windows, you'll get used to it...

 

[Josh S.]

I have the same problem and it pisses me off. When I have my system going, the lights always dim at stoplights.(at night). I even just got a capacitor for it and it still happens. I guess I'm drawing a lot of power and should get a bigger alternator. I also have 5 hellas on the roofrack that I enjoy using, so this, coupled with the headlights and system at idle is baaaad. I'm too lazy to do a search so if someone wouldn't mind telling us all whats a good place to get a bigass alternator and what size is it???(amps)

Isnt the stock one 75a?

 

[justin's_94]

****, you guys need to get some big alts in your vehicles, you need at least a 100 amp alt.

 

[Josh S.]

anybody know where's a good place to get one? I was thinking 200a. Do any of you have these? Would you mind posting about how you like it? Does it slow down your vehicle at all?

 

[Msupertek]

SEE MY POST ON UPGRADING CHARGING SYSTEM

In GENERAL EXPLORATIONS I made a post for this concern. If you have an older model explorer with the 95 amp alternator it is not sufficient for lots of lights, tv and so on. I bought a alternator intended for a 1999 Eddie Baurer 135 amp for $120 and put it on mine because I got tired of the dam lights dimming when I come to a stop. At idle it puts out almost 3 times as much amps and 1.5v more than the stock 95 amp. It does this because it has a smaller pulley with increases the alternators rpm (it will still fit with your stock belt), and the alternator looks giant compared to the current application but bolts right in the same pattern. Check out my posting for actuall specs I recieved while performing a load test with the vat 60 charging system analyzer if you want to see the actual numbers. Me and the guys at my ford dealer (I am a Technician for Ford) got together and started swapping out alternators off different vehicles to see which worked best, the 1999 Eddie X seemed to work out the best although 2002 and up Explorers are now coming with 160 amp capabilities, we found ther wasn't much difference in output between that and the 1999 model when compared to the price difference. Hoped I helped ya.

 

[Josh S.]

oh hell yah man. Thats exactly what I was looking for! Thats badass because it wont be expensive to buy and I bet I could even get it right from kragen. Are they a pita to install?

 

[Msupertek]

AUTO ZONE

I bought it from auto zone for $120 bucks see my charging system posting for specs on output. I checked it myself so its not some bs what I think it will do. Its what it did in front of me. by the way it took me about 15 minutes to install. 15 MINUTES!!!!!!!!!

 

[Josh S.]

Dang thats some reaaaally fast install action! I'm reading through your post right now about the charging system/working. Thanks buddy

 

[Msupertek]

Instruction just in case

Disconnect the negative battery cable, remove your air induction tube (8mm head on retaining clamps), remove throttle cover (8mm head on bolts), use a small flat tip screw driver to help disconnect two connectors on alternator (regulator), remove serpentine belt with by using a 5/8 socket and breakover bar on tensioner to relieve tension on belt, remove 3 alternator retaining bolts (13mm), remove battery power supply cable to alternator on back of alternator (10mm). Install in reverse order. Your Welcome.

 

[Josh S.]

saaweeeeet. I'll do it