my alternator is getting 13.8v

i have a 93 sdv and I have a hi output alt and a 800cc 1000c battery in my car. And I drove it 20 minutes listened to the radio for 10 minutes all factory. I tried to start it ran and went in reverse and it shut off and the no charge light came on. Turned it off and and on again and it started no lights or nothing. And the alt and battery is reading 13.8 and usually it gets 14.4v1993 sdv

Alpine 4x6 6x9 5 1/4 swr-10d4

alpine v60

12.5 VGA flip down

Nettop pc w/10" touch screen

78nova

5-re audio 5x7 ,10" sub &

Xtx-500.5

"Take the faceplate off get the jumperpack"

Are you saying that your voltage doesn't change, engine on or engine off? It's always 13.8V?It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

I haven't checked it with the engine off yet but when it was on it was giving me 13.8 . Its usually 14.25 or 14.50 . I was thinking a doide could be bad or something1993 sdv

Alpine 4x6 6x9 5 1/4 swr-10d4

alpine v60

12.5 VGA flip down

Nettop pc w/10" touch screen

78nova

5-re audio 5x7 ,10" sub &

Xtx-500.5

"Take the faceplate off get the jumperpack"

Sounds like a a bad alternator. Get it checked, or check with headlights & variable RPM etc. Check that your battery hasn't got a collapsed cell that is dragging the alt down. This should be easily recognised if the battery starts glowing (ie, it will get hot).

So I started drove it 20 minutes to gwet everything warmed up and still got 13.80v. But one thing is tht it sometimes it gives a little drag to start. So I'm going to go to autozone and have them test it. My main concern is I have a backup alternator however its factory and I don't have anything aftermarket plugged up to the car other than a bigger battery will I have any problems with the bigger battery and a factory alt. The factory alt is 140a and the hi ouput s 250a. The battery is 800cc 1000c and I belive the factory is 615cc 815c. Here's the update I went on autozone.com and looked at the batteries under my exact year and make, etc and under batteries it had both of them I specified so I'm assuming I should be good till I get my hi output rebuilt. Any suggestions1993 sdv

Alpine 4x6 6x9 5 1/4 swr-10d4

alpine v60

12.5 VGA flip down

Nettop pc w/10" touch screen

78nova

5-re audio 5x7 ,10" sub &

Xtx-500.5

"Take the faceplate off get the jumperpack"

Yep - check your battery first. After resting overnight (else after about 5 minutes with headlights on) measure the battery voltage. It should be 12.5V or above (at ~room temp).

You can turn on all the accessories in your car...radio,blower...etc...Then check voltage with a meter at the battery...If you have a neighbor or a friend have them rev the motor to about 2000 rpm's and see what voltage you have...What are you reading the voltage with...Is it just a display/cap/ with a volt meter on it...Or is this on the instrument panel...? Did the light come on after it shut-off...?M.E.C.P & First-Class

Go slow and drink lots of water...Procrastinators' Unite...Tomorrow!

When I got that reading o 13.8 it was I had the headlights and radio on and when I had the just the radio on . Two different ocassion same result1993 sdv

Alpine 4x6 6x9 5 1/4 swr-10d4

alpine v60

12.5 VGA flip down

Nettop pc w/10" touch screen

78nova

5-re audio 5x7 ,10" sub &

Xtx-500.5

"Take the faceplate off get the jumperpack"

So i went out. Started the car gave a long hard start and I turned the radio and the hi beams on couldn't do the ac needs. To be charged and the alt gave me a soild 14.25 14.50 so I'm lost now . Any suggestions1993 sdv

Alpine 4x6 6x9 5 1/4 swr-10d4

alpine v60

12.5 VGA flip down

Nettop pc w/10" touch screen

78nova

5-re audio 5x7 ,10" sub &

Xtx-500.5

"Take the faceplate off get the jumperpack"

But do the same when not charging - ie, check the battery. Although 140A & 250A alternators may be a bit extreme for this to happen (but it is a big battery), it could be a collapsed battery that is holding down the voltage. AGM/VRLAs can usually accept all charge thrown at them, flooded cells maybe not.    A specific example: (I thought this was an AGM, but victim said it was a sealed flooded battery. He mentions an Optima red-top, but all batteries were Optima.) Someone with a 45A alternator & a single battery - a boot (trunk) mounted battery - suffered from undercharging. They ignored the check-battery suggestion and upgraded to a 75A alternator (after ignoring, er...., much convincing that a bigger 75A wouldn't wreck their newly replaced $350 battery). Problem solved. The a few weeks later, undercharging AGAIN! Luckily he noticed a VERY hot boot battery. He measured 8V across the battery - 2 cells had collapsed. Whilst the upgrade was worthwhile anyhow (from an old external-regulator alternator to a modern internal regulator alternator which eliminates many problems), the twerp missed the obvious.     Furthermore, I await failure of his 3rd $350 battery from under- or overcharging (the 2-wire alternator's IGN feed being too remote from the battery!). Now that dude was a dork (see NotGettingCharge if interested) and I had MANY off-air PM exchanges with the dude... too many for a post-50IQ individual.