amp meter needle is crazy

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crazy 340

crazy 340

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Ok lets Start at the beginning

Last summer I install a 1 wire alternator
You know the small one I think they are OE on Toyota
The guy who sold me this alternator told me it was a 75 amp
I taught it was enough for what I do
Msd
Fuel pump
Fan
Cd player
Amplifier
That's about it

This spring hade battery discharge problem 4amp drop
Went back to the shop he change something in it and call it good
Problem solve

BUt and its a but
Last week end went for a ride and came back home at night
I notice the heads like were blinking a little the dash light did the same
Took a look at the amp needle and it was bouncing

Ps I still use the amp meter but install a second wire from the alternator to the relay starter
Didn't wanna over load the amp meter and have fire or wire problem
I know I'm flying blind a little but the middle stay in the middle of the gage when
The engine running and show a little discharge when everything is running
Mad
Fan
Etch.

Please help me
Ain't the best with wire



Bob
 
crazy 340 said:
Ps I still use the amp meter but install a second wire from the alternator to the relay starter
Didn't wanna over load the amp meter and have fire or wire problem
Click to expand...

This could be causing some weirdness with some current bypassing the ammeter and coming into the dash harness from the battery side.

I'll keep to myself what I think of putting Toyota parts in a Mopar. :disgust:
 
If you have a wire from the battery post of the alternator going to the ammeter and to the starter relay stud, you are still seeing too much amperage to the ammeter. The bulkhead alone is a shunt that maxes at about 55 amps. Bypass the ammeter and get a voltmeter.

I had North Hollywood Speedometer turn my ammeter into a voltmeter. Face looks the same just has VDO movements on the back.

What is the voltage re a ding at idle and above idle at the battery and at the alternator post?
 
When i notice that problem I was going back home with kids and wife didn't took time to verify the voltage that going out the alternator or going in the battery

Will try tomorrow if time let me do it
going for a ride and will bring multi meter and few wrench

The guy. I bought it from told me it could be a regulator problem
He told me to be sure its the alternator the problem I should disconnect it
When it does the problem if the light stay at the same intensity and gage stay calm
In the discharge zone that will be it...��
 
crazy 340 said:
The guy. I bought it from told me it could be a regulator problem
He told me to be sure its the alternator the problem I should disconnect it
When it does the problem if the light stay at the same intensity and gage stay calm
In the discharge zone that will be it...��
Click to expand...

Doubtful it is the regulator but it COULD be. Disconnecting will likely prove nothing

What do you mean "the light?"

Please read the mad article.

"What is worth a try"

DISconnect the battery positive clamp and lay it aside "safely"

Connect a "big" say, no12 made up alligator clip wire or jumper cable, etc, and jumper it from the battery positive post to the alternator output wire. Be careful and wrap the main battery cable in a rag, etc, "it's hot."

Now clip your voltmeter onto the main (disconnected) battery clamp

Clip the other wire to the alternator output connection

This is going to measure voltage drop in the "path" from the alternator to the battery connection pont

Now turn on as much load as you can.....stereo, heater, wipers, headlights.

Read the meter, on low DC volts, I would expect no more than 1/2 volt or so. If more, you surely have a bad connection in that "path."

This can be VERY difficult to run down using the alternator "running."

This is because let's say there IS a bad connection at the bulkhead connector, or at the ammeter.

As the connection "makes and breaks" the regulator in the alternator "hunts" and surges and screws around, trying to keep things on an even track. The voltage surges up and down, and this can "hide" the problem

Alternatively, if the problem IS in the alternator................try this..............

make up a (at least temporary) BIG wire from the alternator output to the main battery stud on the start relay. Use no10, minimum, maybe two or three no 12 in parallel, or larger.

Run the car. Problem still there? (The ammeter will not show this at this time) Monitor battery voltage at the battery.. NO? then it's a wiring problem, as above

If it IS still there, it is surely an alternator problem

Whatever else you do, please READ the Mad article I posted.
 
67Dart273 said:
Doubtful it is the regulator but it COULD be. Disconnecting will likely prove nothing

What do you mean "the light?"

Please read the mad article.

"What is worth a try"

DISconnect the battery positive clamp and lay it aside "safely"

Connect a "big" say, no12 made up alligator clip wire or jumper cable, etc, and jumper it from the battery positive post to the alternator output wire. Be careful and wrap the main battery cable in a rag, etc, "it's hot."

Now clip your voltmeter onto the main (disconnected) battery clamp

Clip the other wire to the alternator output connection

This is going to measure voltage drop in the "path" from the alternator to the battery connection pont

Now turn on as much load as you can.....stereo, heater, wipers, headlights.

Read the meter, on low DC volts, I would expect no more than 1/2 volt or so. If more, you surely have a bad connection in that "path."

This can be VERY difficult to run down using the alternator "running."

This is because let's say there IS a bad connection at the bulkhead connector, or at the ammeter.

As the connection "makes and breaks" the regulator in the alternator "hunts" and surges and screws around, trying to keep things on an even track. The voltage surges up and down, and this can "hide" the problem

Alternatively, if the problem IS in the alternator................try this..............

make up a (at least temporary) BIG wire from the alternator output to the main battery stud on the start relay. Use no10, minimum, maybe two or three no 12 in parallel, or larger.

Run the car. Problem still there? (The ammeter will not show this at this time) Monitor battery voltage at the battery.. NO? then it's a wiring problem, as above

If it IS still there, it is surely an alternator problem

Whatever else you do, please READ the Mad article I posted.
Click to expand...


Tanks Will take a look at it(mad)
What I meen by light is headlights
 
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