What is factory amperage for alternators?
#1
What is factory amperage for alternators?
I think my alternator is starting to kick the bucket. Had the car on a load tester last week. Car running 1100RPM, no load on anything and the alternator was pushing under 20 AMPs. Turned the dial on the tester and the car almost stalled.
I am still getting good voltage at the battery though (14-14.3v).
I'm told this could also be the cause of a small lean condition I'm having right now if the charging system can't keep up.
I am still getting good voltage at the battery though (14-14.3v).
I'm told this could also be the cause of a small lean condition I'm having right now if the charging system can't keep up.
Last edited by falcon; 08-03-2011 at 07:45 PM.
#3
Elite Member
iTrader: (4)
Join Date: Aug 2009
Location: Redwood City, CA
Posts: 1,784
Total Cats: 42
+1 At 20 amps I'd shitcan it and get a new one.
EDIT: 1100 rpm? Alternators are usually load tested at 2000+ rpm. I remember forgetting to take a 2005 Corolla off idle and getting similar numbers, something like 30 amps max, and that alternator is rated for something like 90+ amps.
EDIT: 1100 rpm? Alternators are usually load tested at 2000+ rpm. I remember forgetting to take a 2005 Corolla off idle and getting similar numbers, something like 30 amps max, and that alternator is rated for something like 90+ amps.
#6
Boost Pope
iTrader: (8)
Join Date: Sep 2005
Location: Chicago. (The less-murder part.)
Posts: 33,027
Total Cats: 6,593
I think my alternator is starting to kick the bucket. Had the car on a load tester last week. Car running 1100RPM, no load on anything and the alternator was pushing under 20 AMPs. Turned the dial on the tester and the car almost stalled.
I am still getting good voltage at the battery though (14-14.3v).
I am still getting good voltage at the battery though (14-14.3v).
I mean, the stalling thing makes sense. You need to open the throttle and get the revs up. But if you apply a load to the system and cannot get the alternator to put out more than 20A, and yet the system voltage is not dropping, then something is wrong with the test.
If you want a definitive answer, pull the alternator out and take it to the auto parts store to be tested on the load bench.
#8
I think my alternator is starting to kick the bucket. Had the car on a load tester last week. Car running 1100RPM, no load on anything and the alternator was pushing under 20 AMPs. Turned the dial on the tester and the car almost stalled.
I am still getting good voltage at the battery though (14-14.3v).
I'm told this could also be the cause of a small lean condition I'm having right now if the charging system can't keep up.
I am still getting good voltage at the battery though (14-14.3v).
I'm told this could also be the cause of a small lean condition I'm having right now if the charging system can't keep up.
#9
Boost Czar
iTrader: (62)
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,494
Total Cats: 4,080
1.6L = 60A manual 65A auto
1.8L = 65A manual 70A auto
Last night I logged 11v with the headlights on and a/c running, suffice to say, I'll be getting load tested tonight, I doubt I'm anywhere near 60A.
1.8L = 65A manual 70A auto
Last night I logged 11v with the headlights on and a/c running, suffice to say, I'll be getting load tested tonight, I doubt I'm anywhere near 60A.
#11
Boost Czar
iTrader: (62)
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,494
Total Cats: 4,080
If my 3 month old "refurbed" alt is truely bad, im going to see if I cant get an FC alternator as a replacement unit from them. Should be a direct bolt in (just need a new lower bolt) and produces 80A.
I've been having major electrical gremlins since I replaced my truely bad oem alt, shich allowed voltage spikes-the regulator failed. I wonder if it's the cause...
I've been having major electrical gremlins since I replaced my truely bad oem alt, shich allowed voltage spikes-the regulator failed. I wonder if it's the cause...
#12
You don't always have to stay with a Miata alternator. Often there are numerous options that can be adopted. I used to run 200+ amp Chevy tow truck alternators on an old BMW with a booming sub. They ran around 100 bucks and were bulletproof compared to the considerably more expensive and weaker Bosch alts. All that was needed was new wire terminations and an 8 dollar muscle car L bracket. It had a separate, adjustable VR and could be set to cut back at WOT. There are likely some nice uberlight alts you could load onto a track only Miata.
Thread
Thread Starter
Forum
Replies
Last Post
StratoBlue1109
Miata parts for sale/trade
21
09-30-2018 01:09 PM
Braineack
Cars for sale/trade
3
09-04-2015 02:12 PM