Alternator and gauge

[DCIV]

Just swapped in new batteries, truck starts suuuuper easy now. The problem is the gauge still sits on the line between green and yellow. I let it run and drove it 30 mins...never moved up. I want to put a voltmeter on the battery's but I don't know what I should be seeing numbers wise. Also is there anyone out there that rebuilds our alternators if that is what's happening?

 

[orgnal]

Just swapped in new batteries, truck starts suuuuper easy now. The problem is the gauge still sits on the line between green and yellow. I let it run and drove it 30 mins...never moved up. I want to put a voltmeter on the battery's but I don't know what I should be seeing numbers wise. Also is there anyone out there that rebuilds our alternators if that is what's happening?

The alternator should be putting out 28 volts. It sounds like the alternator is not putting that out and / or something is shorted and is drawing power when you have the start lever in run position.

McReddy

 

[Action]

Put the tester negative on the rear - put the tester positive on the front battery +. How many volts while running?

 

[papakb]

Or take the cap off of the STE-ICE connector and put your meter leads between pins E and F. This is battery voltage. The gauges are lowest bidder products and behave that way. Your alternator may be perfectly fine and your voltmeter could be crap. This goes for every one of them. The small line in the green area should be 28 volts and I usually set the alternator output just slightly to the left of that line, somewhere between 27 and 28 volts. If pins E and F show the system voltage is low you might want to adjust the output of the alternator up. The adjustment on the standard 60 amp alternator is under the allen head screw under the protective cover on the alternator. Use a phillips head screwdriver to make the adjustment. Clockwise DECREASES the voltage, counterclockwise INCREASES it.

 

[DCIV]

Haha! I love this place. I will do this around lunch. Will post back with results.

 

[155mm]

If you are adjusting the voltage, this is a rheostat that is not a continuous circle (you cant go roundy roundy roundy) there are detent stop, so go easy and dont force it.



I will attach a photo when my coffee is done and I walk out to the shop, which translates to... I dont have on pants yet.

You can also use the slave to test volts, inside is hot, outside case is not.

 

[DCIV]

Where is that thing you posted I can test with? Is it at the passenger seat?

 

[bikeman]

Where is that thing you posted I can test with? Is it at the passenger seat?

Yeah, behind the passengers feet/calves give or take.

 

[Wire Fox]

Where is that thing you posted I can test with? Is it at the passenger seat?

Yup. If you walk around your vehicle, the passenger rail should have a plate that says "SLAVE RECEPTACLE INSIDE", to which you should be able to open the door, look at the front of the passenger seat base, and see a squarish opening with a [should be] plastic-capped receptacle. If that cap is on there, it might be an absolute bear to slide off. Mine was very, very stuck and required some tools to help evenly pry it out without breaking it.

 

[orgnal]

Yup. If you walk around your vehicle, the passenger rail should have a plate that says "SLAVE RECEPTACLE INSIDE", to which you should be able to open the door, look at the front of the passenger seat base, and see a squarish opening with a [should be] plastic-capped receptacle. If that cap is on there, it might be an absolute bear to slide off. Mine was very, very stuck and required some tools to help evenly pry it out without breaking it.

Twist first to break it loose. It makes it easier to remove the cap on the recepticle.

McReddy

 

[DCIV]

When I was cleaning the vehicle I found the that cover and saw where to put it, so mine was off and I just pushed it on, wonder why it was off. I wonder if they were having the same issues with the low voltage.

Now when I start messing with the Alternator, can someone tell me "about" how much should I turn it if its not putting out any? Usually when working on all my vehicles you disconnect the battery as well, does the same thing hold true here?

 

[DCIV]

Just tested it. 27.6. Guess it's the gauge! Does anyone make ones that look about the same but are accurate?

 

[papakb]

DCIV, If your alternator isn't putting out anything it's shot and needs to be replaced. Or at least the regulator or brushes do. That adjusting pot only has a 270 degree rotation so don't force it when making adjustments. Your only going to get about a 5 volt adjustment from one end to the other.

When your looking for a replacement gauge it's going to be hit or miss. Personally I think if you can find a gauge made by Stewart Warner you have a better chance of getting a good one rather than one made by Faria although I've had good and bad ones from both manufacturers. This gauge has been around since the early '50s in military vehicles and the only difference between them is going to be the paint color and case material so don't limit yourself to looking specifically for a HMMWV gauge.

Because of the awkward location of the NATO slave receptacle and the power involved I generally don't tell people to look there. Shorting the test leads can cause serious problems. If the STE-ICE connector is still in the vehicle it's a much safer place to make this check.

 

[pjwest03]

Just tested it. 27.6. Guess it's the gauge! Does anyone make ones that look about the same but are accurate?

First, check the voltage at the gauge and make sure that the connection is good and clean.

The VDO 332-902 is a pretty good match for an analog gauge. Wema makes a nice 2-1/16 digital gauge, IEVR-BB-8-32.

 

[bikeman]

When I was cleaning the vehicle I found the that cover and saw where to put it, so mine was off and I just pushed it on, wonder why it was off...

Nah, they fall off on their own accord all the time. Either get it too big or too small, rarely just right.