'97 charge system problem

[WJC97]

My 97 2.3 supercab quit charging last Wednesday. Unfortunately I was 20+ miles from home when the battery light lit and the voltmeter needle dropped (BTW do these trucks have real volmeters, or crappy on/off switches like the oil pressure gauge). Didn't make it home, and the flatbed tow was $120.

After checking fuses and the A terminal (battery) fusible link, I made a bad guess in replacing the voltage regulator and brushes to the tune of $50. Nope. Took the old alternator to Advance, and the diode pack was gone. OK, that explains why it went suddenly.

Bought the new Remy for $180, and damned if it still isn't charging. Low gauge, battery light is on. Connections are clean and tight, plugs aren't corroded or burned, I'm running out of ideas. I did not check the I and S circuits. I guess I need to. Is there some common charging problem on these things I'm overlooking?

 

[R***A**N**G**E***R]

My 97 2.3 supercab quit charging last Wednesday. Unfortunately I was 20+ miles from home when the battery light lit and the voltmeter needle dropped (BTW do these trucks have real volmeters, or crappy on/off switches like the oil pressure gauge). Didn't make it home, and the flatbed tow was $120.

After checking fuses and the A terminal (battery) fusible link, I made a bad guess in replacing the voltage regulator and brushes to the tune of $50. Nope. Took the old alternator to Advance, and the diode pack was gone. OK, that explains why it went suddenly.

Bought the new Remy for $180, and damned if it still isn't charging. Low gauge, battery light is on. Connections are clean and tight, plugs aren't corroded or burned, I'm running out of ideas. I did not check the I and S circuits. I guess I need to. Is there some common charging problem on these things I'm overlooking?

Depending on the condition of your battery BEFORE the alt went out you might of toasted the battery, theoretically you can drive your truck for so long on just BATTERY juice before your truck will completely quit ( depends on what all accessories you are using) anyways, check to make sure your battery is not shot and there is the possibility of a bad alt right out of the box.

If your battery is good and just run completely down because of lack of an alt charging it, it SHOULD charge back up over time assuming the new alt is good.

If you haven't already done this to TEST your new alternator, start the truck THEN disconnect the battery IF the truck dies your alternator is not functioning properly.

 

[WJC97]

I recharged the battery fully. An alternator should never be relied upon to charge a dead battery. And NEVER yank the battery cables from a running modern vehicle. Any number of electronics can be damaged.

Thanks for the awful advice.

 

[adsm08]

start the truck THEN disconnect the battery IF the truck dies your alternator is not functioning properly.

DON'T DO THAT!!!

It used to be a common test of the atlernator. Now its not such a good idea.
It can damage modules, namely the PCM. A much safer test is to put a meter on the battery terminals while its running. 13 to 14 V should be normal for your conditions. Anything less than 12.5 and its discharging, anything more than 14.5 and the light is on because its OVERcharging and probably has a bad regulator.

 

[R***A**N**G**E***R]

i recharged the battery fully. An alternator should never be relied upon to charge a dead battery. And never yank the battery cables from a running modern vehicle. Any number of electronics can be damaged.

Thanks for the awful advice.

you have an old vehicle, it's not new or modern!!!!! Lmao, it is a perfectly fine test.

Do you consider a 13 year old truck NEW??????????

 

[R***A**N**G**E***R]

don't do that!!!

It used to be a common test of the atlernator. Now its not such a good idea.
It can damage modules, namely the pcm. A much safer test is to put a meter on the battery terminals while its running. 13 to 14 v should be normal for your conditions. Anything less than 12.5 and its discharging, anything more than 14.5 and the light is on because its overcharging and probably has a bad regulator.

we are talking about a 13 year old truck ( duh )

 

[TheTopher]

The switched over to PCM engine control in '95 with the OBDII switch. Even my fifteen year old truck could get damaged by that.

 

[R***A**N**G**E***R]

The switched over to PCM engine control in '95 with the OBDII switch. Even my fifteen year old truck could get damaged by that.

Prove it or shut up.

 

[adsm08]

Prove it or shut up.

He's right. Basically you don't want to do that to anything with electronic fuel injection but its worse on post 95 vehicles with the OBDII system since there are more modules to fry. And since my truck is 23 years old and still going strong, yes I do consider a 97 to be "new"

 

[dennis461]

I vote no on this one

Prove it or shut up.

Try it on your rig first

A real simple test is to see how bright the headlights are with engine running, then shut off engine with lights on.
It should be easy to spot a difference if the alternator is working.

Is the Remy an internal voltage regulator ?
Your original had the regulator internal with the brushes, correct?

 

[R***A**N**G**E***R]

Try it on your rig first

A real simple test is to see how bright the headlights are with engine running, then shut off engine with lights on.
It should be easy to spot a difference if the alternator is working.

My wifes 97 Taurus had a bad alternator 3 months ago and that is how i tested it

 

[Bob Ayers]

DON'T DO THAT!!!

It used to be a common test of the atlernator. Now its not such a good idea.
It can damage modules, namely the PCM. A much safer test is to put a meter on the battery terminals while its running. 13 to 14 V should be normal for your conditions. Anything less than 12.5 and its discharging, anything more than 14.5 and the light is on because its OVERcharging and probably has a bad regulator.

+1 .............Very stupid suggestion to remove a battery cable while the engine is running!! The di/dt can create huge voltage splikes.

 

[adsm08]

My wifes 97 Taurus had a bad alternator 3 months ago and that is how i tested it

and you got lucky. They also tell you to unhook the battery before unplugging/plugging in the PCM. Just because it doesn't always fry it when you don't, doesn't mean the chance isn't there. You keep doing it that way. One of these days you'll buy an alternator and a PCM.

 

[R***A**N**G**E***R]

and you got lucky. They also tell you to unhook the battery before unplugging/plugging in the PCM. Just because it doesn't always fry it when you don't, doesn't mean the chance isn't there. You keep doing it that way. One of these days you'll buy an alternator and a PCM.

Luck has nothing to do with it.

 

[R***A**N**G**E***R]

+1 .............Very stupid suggestion to remove a battery cable while the engine is running!! The di/dt can create huge voltage splikes.

Not stupid at all.