Replaced 200A Alternator showing 40V+ on 24V and 20V+ on 12V

[Roger0that!]

Hello,

I have a 2003 M1123 that have been working on for quite some time now. Recently after replacing GLow plug control box, many other things my batteries stopped charging, then I noticed taht the voltage on the 24V prong on the voltage regulator it was giving me an error (set for 200V on tester) then the 14V was showing excess of 20-30V (it fluctuates). I then replaced the regulator, same problem, added a grounding kit, same problem. I then removed all terminals, cleaned them, tightened, same at the starter and continue with the same problem.
I have replaced the alternator and a new Regulator, same problem. I AM ABOUT TO GO CRAZY WITH THIS THING!!!
I am inclining that it could be that the glow plug control box is faulty is this is a rebuilt, anything else that I need to check? I will install the old glow plug box and see if it makes any difference.

HELP!!

 

[RageMachine]

 

[RageMachine]

 

[Milcommoguy]

Do you believe your meter?? Check it against a known source. What does the volt meter read in the gauge cluster? What is the ?? error voltage? didn't say. Do you have the 14 v tap going to the batteries? Is the wait light working and do you get a glow plug activation?

Hard to see where your test leads are connecting. Those high voltages NOT good for the Blue HumV.

Important questions to get a better feel as to what is up with BLUE.

More questions are being ask of the SCOTUS nominee, CAMO

 

[Milcommoguy]

Do you believe your meter?? Check it against a known source. What does the volt meter read in the gauge cluster? What is the ?? error voltage? didn't say. Do you have the 14 v tap going to the batteries? Is the wait light working and do you get a glow plug activation?

Hard to see where your test leads are connecting. Those high voltages NOT good for the Blue HumV.

Important questions to get a better feel as to what is up with BLUE.

More questions that are being ask of the SCOTUS nominee, CAMO

Have to ask....

 

[mechanicjim]

so you have change Alternator and Regulator, cleaned terminals, added ground kit. and have the same reading on the meter? my guess is its a bad meter spend a few bucks and pick up an AC/DC clamp meter make sure it has a DC amp reading( A with three dots above a line) itll come in more handy than just a straight DMM meter.
like this one

CM610A 600A T-RMS AC/DC Clamp Meter

Amazing deals on this 600 A T-Rms Ac/Dc Clamp Meter at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

or this one which is available at Lowes

400A AC/DC Clamp Meter with True RMS, Built-In NCV, Worklight, and Third-Hand Test Probe Holder | Southwire

400A AC/DC Clamp Meter with True RMS, Built-In NCV, Worklight, and Third-Hand Test Probe Holder

www.southwiretools.com

double check once you have that you can also use the clamp meter to see if ALT is outputing any Amps or how many Amps the Batteries are taking in.

Also check the battery in your meter replace it with a known good one of a good brand.

 

[Retiredwarhorses]

Cant see anything, is the meter even set on the correct setting?
as others have mentioned, what does the gauge panal read? In the green?
the voltages you stated melt your gauge....

 

[Roger0that!]

Do you believe your meter?? Check it against a known source. What does the volt meter read in the gauge cluster? What is the ?? error voltage? didn't say. Do you have the 14 v tap going to the batteries? Is the wait light working and do you get a glow plug activation?

Hard to see where your test leads are connecting. Those high voltages NOT good for the Blue HumV.

Important questions to get a better feel as to what is up with BLUE.

More questions are being ask of the SCOTUS nominee, CAMO

OK so, I did use a Power Probe as well to ensure that the Meter is fine. After further testing for continuity and after using the Power probe I noticed that my AC on the Voltage Regulator was grounded.
Disconnected the cable for the AC: Cable checked as no ground or continuity. Checked the Regulator and it does have continuity. As soon as I move the Regulator from the alternator it looses the continuity, so at this point my guess is a bad Regulator.

I would like to point that I doubted that since I have installed 3 Regulators. (the one that came with the vehicle, One that I purchased on Ebay and One that came on the new alternator, ALL BAD!!! REALLY!!!

Should get the new Regulator today and I will update!!!

Thank you guys for your help and responses

 

[Roger0that!]

Cant see anything, is the meter even set on the correct setting?
as others have mentioned, what does the gauge panal read? In the green?
the voltages you stated melt your gauge....

I assume the reading is an error since the safe switch on the regulator probably kicked in! but initially it was fluctuating

 

[Retiredwarhorses]

It appears you have an A2 truck, your 14v tap should have a cable running from the regulator to the positive battery lug on the rear battery. that regulator needs a load on the 14v to be active with voltage.
the 200amp Gen charges the batterys direct from the large positive lug on the Gen and lands on the positve
battery strip in the battery box.
the 14v tsp is only grounded to the generator in a v-belt truck with no 4 speed transmission

 

[Retiredwarhorses]

OK so, I did use a Power Probe as well to ensure that the Meter is fine. After further testing for continuity and after using the Power probe I noticed that my AC on the Voltage Regulator was grounded.
Disconnected the cable for the AC: Cable checked as no ground or continuity. Checked the Regulator and it does have continuity. As soon as I move the Regulator from the alternator it looses the continuity, so at this point my guess is a bad Regulator.

I would like to point that I doubted that since I have installed 3 Regulators. (the one that came with the vehicle, One that I purchased on Ebay and One that came on the new alternator, ALL BAD!!! REALLY!!!

Should get the new Regulator today and I will update!!!

Thank you guys for your help and responses

whats the part number to the regulators you are using?

 

[RageMachine]

whats the part number to the regulators you are using?

 

[Retiredwarhorses]

View attachment 815161

those are correct

 

[Roger0that!]

whats the part number to the regulators you are using?

The regulator number is

those are correct

Replaced the regulator and bought a new multimeter. Same problem and outrageous numbers coming out of the regulator.

 

[Retiredwarhorses]

What’s your reading at the batteries when running?

 

[RageMachine]

What’s your reading at the batteries when running?

24.5V and 14.5V
Today I disconnected the 24V and 14C cables from the alternator and the output on the 24v probe was 0.625 volts or 625 minivolts and 0 on the 12 V side on the inverter.

 

[Retiredwarhorses]

14.5 volts is the correct output for the 14v tap...these gens have a soft start feature, it takes about 30 seconds to start output, and needs a load. It’s possible I guess the new box is causing an issue, have you put the old back in?

 

[RageMachine]

14.5 volts is the correct output for the 14v tap...these gens have a soft start feature, it takes about 30 seconds to start output, and needs a load. It’s possible I guess the new box is causing an issue, have you put the old back I’m?