What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

Charging issue. at 16.8 volts

Sorry that I am slow to see this, but is it a CS130 alternator?

Check to make sure that the alternator has a good, clean ground.
I have heard of the alternator ,or the bracket not having a good ground, which makes the regulator crank up the voltage to get the correct reading. Butit doesn't know that it is wrong due to bad ground circuit.

Just something to check.
 
It was a bad conection at the starter from the junction block from the alternator that feeds power to the starter
 
6872xtc said:
Sorry that I am slow to see this, but is it a CS130 alternator?

Check to make sure that the alternator has a good, clean ground.
I have heard of the alternator ,or the bracket not having a good ground, which makes the regulator crank up the voltage to get the correct reading. Butit doesn't know that it is wrong due to bad ground circuit.

Just something to check.
Click to expand...
i dont know the terms for alternator but i put a serpentine belt kit from gm on it. so it is not stock
 
Ok, I would guess that it is a CS130 then. I believe that it is possible for it to turn the voltage up to get the proper voltage at the battery. The older ones I don't think will do it to that extent, unless there is an internal problem.

You can check for resistance between the alternator case, bracket, engine and battery. Just use an ohm scale on a meter, but also check for voltage drops at the same locations.
I think that you could use jumper cables to ground the alternator case directly to the negative battery terminal.
If you do that with the truck running and the volts change very much, then you can find the problem on the ground side.
 
I went back through and noticed that Chris Perry said the same thing about the jumper cables ...
 
Diesel its an 85 , Aaaand It WAS a Diesel 6.2. The wire I see is a red/purple that I cannot find any branchoff into the cab. The red ties to a fused yellow smaller gauge wire hooked into the junction on the FW along with Alt sense and other hot feeds. I've read the starter solenoid wire is purple too but the one that kicks my starter is Red (?? inlaw ingenuity??) and I've never experimented with the purple,which is cut dead and taped in the bundle over the MC.
 
evolve991 said:
Diesel its an 85 , Aaaand It WAS a Diesel 6.2. The wire I see is a red/purple that I cannot find any branchoff into the cab. The red ties to a fused yellow smaller gauge wire hooked into the junction on the FW along with Alt sense and other hot feeds. I've read the starter solenoid wire is purple too but the one that kicks my starter is Red (?? inlaw ingenuity??) and I've never experimented with the purple,which is cut dead and taped in the bundle over the MC.
Click to expand...

The red one may have been the hot feed for the glow plugs and their relay ?....someone may have changed the crank wire to a red one,just about every GM I have had ,used a purple wire to deliver the "crank" power to the solenoid "S" terminal...but with all the variations in harnesses,its possible that not all use the same color codes..
 
Yeah about every GM I owned was a purple to S and red to I on the starter but as I said this was a backyard rushjob and I haven't had the nerve to retrace it all....guess I will now.....and a new problem.....Voltmeter drops hard with turn signal,headlights etc now....so checking all grounds etc too.....Long story short my grandsons ,2 and 3, were in my truck last weekend aaannnd who knows what got yanked......
 
You must log in or register to reply here.

Latest Posts

Top Bottom