Volt guage - charging- alternator issue

[BobMassive]

Hello.
My volt gauge is reading low. Cleaned it, tightened it and it still reads in yellow before and during starting. It is just into the green while running. I have manual glow plugs. So I started testing...

Batteries (off) read 12.6

Front batt (running) read 14.5
back reads 14.8
Across both reads 29.3

Is this indicative of a charging problem or am I making something out of nothing?

On Gen 2 (passenger) the red wire (off) reads 25.5

Brown wire (on) reads 15.3

The large red wire reads 24.8

Is the brown wire at fault?

On Gen 1 (driver) the red wire (off) reads 12.7

Brown wire (on) reads 8.02

The Large red wire reads 12.55

The brown wire again?

Sorry if this is confusing. I can do the tests and follow the other threads but just cant make sense of the numbers. The truck runs fine otherwise. I have cleaned the grounds but havent traced anything beyond the alternators yet.

So what do I look at next?
thank you

 

[BobMassive]

In addition. Both Gen lights come on prior to starting. With the dash off and the truck running I can see that the Gen 2 bulb is lit just enough to color the filament but not enough to actually light up.

 

[762luver]

Troubleshoot according to the TM. It's all there you just have to go through it in detail.

I had similar issues with my '09 when I got it. Clean contacts, check the volt meter and Alt 2 relays and any other wiring you can get to. Just cleaning the various electrical connections worked wonders for me.

You have to get your hands dirty to drive Old Iron.

 

[BobMassive]

Yeah I will certainly go over every connection again. Couldve sworn I just cleaned everything a few months ago! Really I was hoping I could rule out the alternators as the problem. Originally I thought that Gen 2 was over charging (possible voltage regulator problem).

 

[idM1028]

I'd say start tracing down those brown wires. Those voltages sound WAY too low... IIRC they should be or fairly close to 12V for GEN1 and 24V for GEN 2. The voltages you're getting are 2/3 of the voltage of the red wires. You'd be surprised how much cleaning up contacts can help. I've seen noticeable voltage gains after cleaning up terminals and contacts. Probably like 1-2 volts. And to help you trace down those brown wires, ladies and gentlemen for your viewing pleasure...