Thought my 3G went bad. Was heading to the jy, so I grabbed another one. Same problem.. After a jump start, the voltage settles to the batt voltage, about 11.5 and SLOWLY drifts up to about 12.6 (like 3 minutes).

Anything that draws current (headlights) slowly drops the voltage back to about 11.5. Battery is about 4 months old, 650 CCA.

Take both alts to autozone and they both test just fine.

Heavy gauge wires. Clean crimp connections. I even bolted a 6ga gnd wire from the alt case to the block. I have studied the 3G hookup diagrams till I am blue in the face.

I am clearly doing something really stupid. Bad connector? The belt is not super tight and I'm at the limit of adjusting it. No squealing. Could the belt be slipping when a load gets applied? I'm clueless.

 

I'd check the belt first. They can slip without squealing.

 

1) Verify the 3G yellow wire loops back onto either the charge post or connects somewhere near the + post of the solenoid.

2) Double check you have the Green/Red from the 3G connected to the factory Green/Red or to a KEY-ON 12+ volt source.

Other than those two things, that's all there is to it. The green/red (or red/green) is the important one, once it sees voltage it "excites" or turns on the alternator.

Josh

 

Yellow connects to +batt at the starter solenoid. Grn-red wire connects to +batt run connection on solenoid. If I remove this wire with the car running I can definitely feel and hear the load change.

So i have a slipping belt or a bad connector, right? That's all that is left. Also, since it used to work fine, belt stretching would be the best bet. I think.

 

I think the red text above is your issue. Here some real-life pics and notations to help ya out.

 

Whoa! Yeah Definately swap the red/green to the old, pre-existing red/green or connect to a known and good key-on power source.

Josh

 

Guys, I appreciate the help, but there is obviously something I'm not getting..I thought if the grn-red wire was on the 'run' terminal of the solenoid that that was the best place to put it. What am I missing?

 

There is no "RUN" only + from the battery, large lug to starter, "S" terminal to engage starter and the "I" terminal to supply full battery voltage to the coil during crank.

Red/green needs a full and constant power source.

Josh

 

Which terminal are you calling the "run" terminal? There are four terminal on the starter solenoid. The "big" battery terminal, this is hot all the time. The other "big" terminal goes only to the starter and is hot only when the key is in the start position. The small "s" terminal receives voltage when the key is in the start position to energize the solenoid and the other small terminal "I" also is only hot when the key is in the start position, this shoots 12v to the ignition for starting.

EDIT: Josh beat me to it.

 

Uhhhh....I thought the I terminal was always hot during "run". I told you I wasn't getting it.

So why don't you just tie it to +batt all the time?

 

The "I" terminal is only hot when the solenoid is engaged, and the starter is cranking. It's only purpose is for the coil start bypass circuit. It has nothing to do with the charging system. As soon as you release the key from START and the solenoid dis-engages, the "I" terminal goes open circuit.

GREEN with a RED stripe needs to be hot-in-RUN. You don't want it connected to hot at all times because this will dump current through the alternator rotor windings with the engine off, and drain the battery.

 

Well boys, I think we've found the problem. Thanks a lot.

I hate being the slow kid in the class.

 

What's awesome is you hung in there, asked more questions and for what it's worth looks like the problem is figured out.

All too often someone posts a question or problem, several posters offer responses and either:

A) Never hear from the OP again
B) The OP gets offended or biligerant for whatever reason



Josh

 

Or C) "certain" members start arguing about it.

 

Got that right. I'm certainly guilty of that at times.

Especially if you have B, followed by A and get a raging case of C.

Josh