So I blew another alternator tonight... - United Bimmer Community

**komodo** · 11-17-2005, 09:06 PM

I blew my alternator again tonight.

And almost everything was off this time too.

My question is what options do I have for stablizing my power source? Can I add a 2nd alternator, or would a 2nd battery help? What can I do to get more power to my car?

This is what I have that requires power beyond the normal car operations (like a/c):

-Motorized flip out lcd screen on head unit

-Headunit brain (powered) mounted behind glove box

-Full sound system, two 12" subs, amp, etc.

-Full 2.8GHz computer system

-Additional LCD touch screen mounted in place of OBC and sunglass holder

-Powered finger print scanner mounted in ash tray

-wireless keyboard reciever mounted under back seat

-8" high defination LCDs mounted in both sun visors

-Power invertor and full Playstation 2 system mounted in glovebox

-All interior lights changed from yellow to white halogen (not sure if that draws any more power or not)

-Valentine 1 radar detector

I think that's all.... so you can see there's a lot of electrical stuff in my car. What are my options for supporting it?

Thanks.

**///Menace328i** · 11-17-2005, 09:09 PM

Quote:

Originally Posted by komodo

I blew my alternator again tonight.

And almost everything was off this time too.

My question is what options do I have for stablizing my power source? Can I add a 2nd alternator, or would a 2nd battery help? What can I do to get more power to my car?

This is what I have that requires power beyond the normal car operations (like a/c):

-Motorized flip out lcd screen on head unit

-Headunit brain (powered) mounted behind glove box

-Full sound system, two 12" subs, amp, etc.

-Full 2.8GHz computer system

-Additional LCD touch screen mounted in place of OBC and sunglass holder

-Powered finger print scanner mounted in ash tray

-wireless keyboard reciever mounted under back seat

-8" high defination LCDs mounted in both sun visors

-Power invertor and full Playstation 2 system mounted in glovebox

-All interior lights changed from yellow to white halogen (not sure if that draws any more power or not)

-Valentine 1 radar detector

I think that's all.... so you can see there's a lot of electrical stuff in my car. What are my options for supporting it?

Thanks.

Do you have a cap on your amp?

**komodo** · 11-17-2005, 09:11 PM

Quote:

Originally Posted by 3twenty8i

Do you have a cap on your amp?

A 3 farad cap..... 3,000 watts.

craig · 11-17-2005, 09:13 PM

again? wow.. and what in the world is the finger print scanner for?

**///Menace328i** · 11-17-2005, 09:14 PM

hmmmm.... that's a tuffy bro.... under drive pullies? audiophile I hope!

**komodo** · 11-17-2005, 09:17 PM

Quote:

Originally Posted by shpuz

again? wow.. and what in the world is the finger print scanner for?

The computer, so I don't have to type in my password each time I want to login. I can just swipe my finger and it's good to go.

3twenty8i, I have under drive pulleys on everything EXCEPT the alternator, obviously.

Anyone know what I can do to add more power?

**xsperf** · 11-17-2005, 09:17 PM

for logging on the computer, i think

komodo, you shouldnt just blow an alternator like that, are you sure everything is wired correctly?

**Rooz** · 11-17-2005, 10:00 PM

lmao, even I don't know the answer to this... give me a few days and I'll ask around... but my guess is Bigger alt....

**Spieluhr** · 11-17-2005, 11:28 PM

^^^
i think he went with the biggest OEM option he could. anything bigger might require modification or some type of bracketry.

this is really weird. This sounds too obvious, but make sure your alternator cooling duct is in tact, if it isn't, then your alternator will overheat because of all of this stress and it will blow.

my advice would be looking into this problem more thoroughly, i don't see why you should be blowing alternators like this.

and hopefully that new alt. had a warranty, it's only been like a month.

drz · 11-17-2005, 11:31 PM

Put is a new cooling duct. I would also recommend looking into upgrading your wiring (go thicker). Also, adding a second battery in parallel should help. Get the warranty replacement alternator -- maybe you just got a bad one.

**xsperf** · 11-17-2005, 11:57 PM

its probably not a bad one, considering his OEM blew too.. but harry i think you may have a short or something thats putting a lot of stress on it which is causing it, because really, you had relatively the same amount of electronics(the same thing - the sun visors + PS2) on the old alternator, which was much smaller, and you ran that fine for a WHILE and then all of a sudden it went out, then a month later, with a MUCH bigger alternator it goes out again

**Spieluhr** · 11-17-2005, 11:59 PM

^^^
all good and cheap ideas.

**Cellardoor** · 11-18-2005, 12:18 AM

i would think about looking into the audio preformance batterys such as http://www.1st-optima-batteries.com/...io_battery.asp mayb thinking wireing, and double check everything.

-Hutch-

**c1apton** · 11-18-2005, 12:30 AM

Asuming your wiring is correct and your "toys" aren't FUBARRED try this:

When upgrading to a higher output alternator you should always install a larger wire between the alternator and* battery. Even with a standard output alternator you will get better performance and life out of your alternator if you upgrade the main battery wiring. The original wire just isn't large enough for proper power transfer.*
If you are using your alternator to it's maximum output or when you*upgrade to a higher output Alternator you must increase the wires size. An alternators*ability to send the power it is making to the battery is directly related to the wire size*and quality of connection between the alternator and battery.
*Also, a wire that is to small when used on a high output alternator can cause the power to back up within the alternator making it overheat, burn up and fail.*

Another area that little is paid attention to is the ground. You must also improve the ground as well. A poor ground will hinder the alternators ability to send power to the battery and can burn an alternator up just as fast as an inadequate alternator to battery wire. Your ground may be fine when you first install your alternator but over time corrosion and resistance builds up in the ground connections. This is why it is best to run the ground directly from the rear of the alternator to the battery.

Here is another great auto electric tip from Randy DuBois on upgrading the wire between the alternator and battery. Randy says, you do not need to rip out your old wiring when upgrading. You can piggy back a second wire between the alternator and battery. The main battery wire connected to the back of the alternator has power to it at all times, even when the vehicle is shut off.* You connect this wire like normal then you run a second wire between the alternator and battery. The power coming out of the alternator will treat the two wires as one, power follows the path of least resistance.*

On a safety note, when running the second wire you should fuse it near the battery. The fuse is just in case the wire gets pinched or shorted out, the fuse will blow instead of the wire burning up. You should use the largest fuse you can for the wire size, fuses are restrictive to current flow. Typically you want the fuse value to equal 80% of the wires load carrying capacity.*

**xsperf** · 11-18-2005, 12:46 AM

Quote:

Originally Posted by c1apton

The original wire just isn't large enough for proper power transfer.

really? thats interesting, good points