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thathotrodlincn
06-19-2011, 06:30 PM
Alternator failed today. Some goofball broke the plastic housing that contained the output stud and tried to GLUE it together. Needless to say it failed.

The replacement unit was a 130 amp unit. Works, however, the battery light cycles on and off. Any suggestions as tom the cause? Any help greatly appreciated.

Thanks,
Bill
F8LBITEva
06-19-2011, 06:35 PM
Aftermarket alternator ? Did you check the battery too?
slickster
06-19-2011, 07:02 PM
Befor your alternator went did you notice your interior lights pulsating. Cause I think mine is going bad also
thathotrodlincn
06-19-2011, 07:25 PM
New battery, reman Ford alt with black voltage regulator (old one was white). Voltmeter (real) is stable at about 14.0 volts - no dips or spikes. Whole thing started with tensioner and idler replacement. While removing alternator for bearing check, the output stud fell off. Other than the battery light, all else is normal.
RoyLPita
06-20-2011, 05:32 AM
According to Ford, ours is a 120 amp.
thathotrodlincn
06-20-2011, 05:41 AM
According to Ford, ours is a 120 amp.

Thanks for the info. However, the difference in the output (120 vs 130 Amp) would have no bearing on the battery light. As I understand the PCM controls the alternator and sends a signal to turn on/off the battery light in the instrument panel. This makes me think that there maymbe something in the black voltage regulator causing this. Opinions and help please.
RoyLPita
06-20-2011, 06:23 AM
Thanks for the info. However, the difference in the output (120 vs 130 Amp) would have no bearing on the battery light. As I understand the PCM controls the alternator and sends a signal to turn on/off the battery light in the instrument panel. This makes me think that there maymbe something in the black voltage regulator causing this. Opinions and help please.

It would if the PCM is believing the alternator is overcharging the battery because of the output change.

This is why I recommend a Ford Alternator over anything aftermarket.
RacerX
06-20-2011, 06:36 AM
Hmmm... I never had a single issue with my 220 amp alternator...
Blackened300a
06-20-2011, 07:30 AM
The Marauder alternator has a specific regulator on it with its own part number. Its possible you have a regular 4G alternator with a generic regulator on it.
I leaned all this while shopping for a alternator recently.
RF Overlord
06-20-2011, 10:16 AM
I second what Blackened300a said.
thathotrodlincn
06-20-2011, 01:25 PM
The Marauder alternator has a specific regulator on it with its own part number. Its possible you have a regular 4G alternator with a generic regulator on it.
I leaned all this while shopping for a alternator recently.

Gentlemen,
Anyone know the correct part number of the regulator or for the alternator assembly?
I am thanking you in advance.
fastblackmerc
06-20-2011, 02:53 PM
Gentlemen,
Anyone know the correct part number of the regulator or for the alternator assembly?
I am thanking you in advance.

I don't think you can get the regulator separately, unless you knew someone that repairs them.
Blackened300a
06-20-2011, 03:25 PM
I don't think you can get the regulator separately, unless you knew someone that repairs them.

Correct, unless you pickup a rebuild kit from the dealer.
4play
06-21-2011, 09:27 PM
I thought our alt's had a clutch system that could turn on and off the alt under wot ?
RF Overlord
06-22-2011, 04:42 AM
Let me try to relieve all the confusion; the MM alternator has TWO separate systems, one mechanical and one electronic. The mechanical part is the overrunning clutch which actuates when the motor is turning at high speed and suddenly slows, like during a shift. The electronic part allows the PCM to control the alternator's output to match the load. This system is also capable of shutting the alternator off during WOT to reduce drag.
screamn
06-22-2011, 05:03 AM
I'm assuming that in order to have the alternator shut off @ WOT, I thought that I need a programmer or tuner with this option installed?

Also, several times @ WOT, I look at my Volt gauge & it still reads above 13 to 14 volts & I don't have a tune. All stock. So I'm assuming this is an aftermarket option & not from factory???
Blackened300a
06-22-2011, 06:12 AM
I'm assuming that in order to have the alternator shut off @ WOT, I thought that I need a programmer or tuner with this option installed?

Also, several times @ WOT, I look at my Volt gauge & it still reads above 13 to 14 volts & I don't have a tune. All stock. So I'm assuming this is an aftermarket option & not from factory???

Its from the factory. My tuner turned this feature off and gave me some story about how I wouldn't want less voltage to my fuel pump at WOT. :rolleyes:
massacre
06-22-2011, 06:21 AM
You certainly can buy the regulator seperately.
I thought that the MM had the GREY regulator?
You said the new one is black, and the old one was white?
stryker
06-26-2011, 07:27 PM
:confused: I have plans to replace the existing alt in my 2000 CVLX for a 250 amp, the reason to install that alt is that I will install a powerful sound equipment which include a 3.5 Farad capacitor, strobe lights and siren the alternator is phisically the same as stock just that has more amperage, any advises will be welcome and thankfully. :cool:
FordNut
06-26-2011, 08:13 PM
MM should have the white regulator.
fastblackmerc
06-26-2011, 08:37 PM
:confused: I have plans to replace the existing alt in my 2000 CVLX for a 250 amp, the reason to install that alt is that I will install a powerful sound equipment which include a 3.5 Farad capacitor, strobe lights and siren the alternator is phisically the same as stock just that has more amperage, any advises will be welcome and thankfully. :cool:

Here is what you want..........

http://www.dbelectrical.com/p-5458-crown-vic-towncar-chrome-alternator-high-220-amp-output-98-02-7795.aspx
massacre
06-27-2011, 04:26 AM
MM should have the white regulator.

OK thanks for the clarification. I couldn't remember.
I have a leftover white one that I won't be using.....
stryker
06-27-2011, 07:44 PM
Here is what you want..........

http://www.dbelectrical.com/p-5458-crown-vic-towncar-chrome-alternator-high-220-amp-output-98-02-7795.aspx Thank you mang but it not work with my panther, my Panther is not a POLICE INTERCEPTOR and I read in the link that if is not a police package will not fit, also is a 220 amps and i'm looking for the 250 amps, but I appreciate your contribution a lot, other thing here between you and I if DOOM mang see the chrome he cloud drool over and think that i'm competting with him, ha ha ha !
stryker
06-27-2011, 08:02 PM
http://www.mercurymarauder.net/gallery/data/500/medium/250ampalt.jpg (javascript:;)
This is the one i'm looking for it is same form and style of the one currently have BP74i but... ¿ How I know if is 250 amps ?
longbid
09-13-2011, 05:21 PM
4G (Fourth Generation) alternators have a ground problem.
The two halves corrode and let the alternator undercharge.
A solution is to scratch off the paint on the rear black cover and ground it to the negative battery terminal.
If that helps the charging problem then remove one of the actual alternator thru bolts and make a 8 guage or lower ground cable and connect it to the battery,
I did mine to a boss in the passenger side cylinder head with a self tapping 5/16 inch screw.
Works great.
My problem was a low charge without the battery light on in the dash.
I am now at 14.5 happily.