crash-harris
Breaker! Breaker!
I'm very close to calling it on all fronts mechanical. Thought about just plowing into a bridge support on the way home this afternoon with everything that has been going on here (BAD vehicle screwjoo).
Sorry in advance for the long read...
Since the MOMENT I started the truck after installing the new 6.0L GP harnesses, it has been refusing to charge correctly. I have a 130A 3G, Duralast reman with a 1/0 cable running from the alternator to a 200A resettable breaker, then another 1/0 cable to the fender mounted starter relay. All battery cables, both positive and grounds are also 1/0. All the eyelets on the positive cables up to the fender mounted relay have 5/16" holes in them (couldn't find any smaller for the alternator output or breaker), and are soldered on and adhesive hearshrinked. I followed the harness wiring from the diagram in the tech section (same as when I did the swap on my 300 almost a decade ago). The charge sense wire was previously connected to the battery terminal, but I moved it to the output side of the breaker. All harness connections for the alternator are soldered and heatshrinked (had them crimped before all this, soldered them to eliminate possible cause of my no-charge problem). Oh, and the battery light on the dash hasn't burnt out. I also have a digital voltmeter in the cab that is connected directly to the driver's side battery terminals.
Some of you may remember that a few years ago I had a fusible link burn up due to some grounds missing. There's now a 8ga cable running from the back of the intake to the wiper motor, a braided ground strap from the core support to the frame rail where the driver's side battery is grounded, a factory strap from the cab to frame and two parts store 1/0 cables running from the factory block ground location on the passenger side routed to the battery ground locations on either frame rail (driver's side of the block was missing the bolt, couldn't find another or the thread pitch without buying other tools).
I cut the weatherpack connectors off the new harnesses and crimped 2 wires each into 5/16" ring terminals (so 4 total) and installed them in place of the existing harness that was just bits of 10ga wire hand-wrapped and tapped together (didn't know that before replacement). After finishing up, I started the truck to move it back to its parking spot and was only running on battery voltage. I removed the breaker from the equation and connected both cables on either side of it to the same post with no change. I thought that the 3G alternator or regulator had suddenly decided to die after almost a year (or less?), so I replaced that. New reman alternator had an actual Motorcraft regulator on it. Truck seemed to charge better (14V at idle) until the next time it left the driveway. It wouldn't charge over 14V. I fought with this for a bit until I heard belt squeal, tightened the belt and all seemed normal. So I got new belts (also Duralast, same as the old) and put them on right after it stopped charging again with no change. At that moment, I revved the engine up to about 3K and it started charging. Research indicates that the alternator/regulator aren't self-exciting, but will kick on when reaching threshold speed to excite. Still not sure why 2 alternators suddenly decided to no longer self-excite.
Today when we left the house to pickup our Hyundai from the stealership service center, it seemed week (13.9-14V at any engine speed). After getting the car, the truck just refused to charge, no matter what. I took the breaker out of the equation again with no change. I started at the stealership at 12.4V and was at 12.1V when I got home (cracked the window a few inches then rolled back up later and radio was on with volume off).
I don't understand what's going on here, or why this is suddenly an issue rearing its head after swapping to 6.0L GP harnesses. I've made sure I didn't touch anything else on the GP controller (but I do remember removing the large nut and one smaller one from it and reinstalling them). I even pulled the engine harness connector apart again to make sure that wasn't causing problems and it's still packed with dielectric grease from when I did the Molasses Carnage Corrections. Am I missing something, or do I need an exorcist?
Sorry in advance for the long read...
Since the MOMENT I started the truck after installing the new 6.0L GP harnesses, it has been refusing to charge correctly. I have a 130A 3G, Duralast reman with a 1/0 cable running from the alternator to a 200A resettable breaker, then another 1/0 cable to the fender mounted starter relay. All battery cables, both positive and grounds are also 1/0. All the eyelets on the positive cables up to the fender mounted relay have 5/16" holes in them (couldn't find any smaller for the alternator output or breaker), and are soldered on and adhesive hearshrinked. I followed the harness wiring from the diagram in the tech section (same as when I did the swap on my 300 almost a decade ago). The charge sense wire was previously connected to the battery terminal, but I moved it to the output side of the breaker. All harness connections for the alternator are soldered and heatshrinked (had them crimped before all this, soldered them to eliminate possible cause of my no-charge problem). Oh, and the battery light on the dash hasn't burnt out. I also have a digital voltmeter in the cab that is connected directly to the driver's side battery terminals.
Some of you may remember that a few years ago I had a fusible link burn up due to some grounds missing. There's now a 8ga cable running from the back of the intake to the wiper motor, a braided ground strap from the core support to the frame rail where the driver's side battery is grounded, a factory strap from the cab to frame and two parts store 1/0 cables running from the factory block ground location on the passenger side routed to the battery ground locations on either frame rail (driver's side of the block was missing the bolt, couldn't find another or the thread pitch without buying other tools).
I cut the weatherpack connectors off the new harnesses and crimped 2 wires each into 5/16" ring terminals (so 4 total) and installed them in place of the existing harness that was just bits of 10ga wire hand-wrapped and tapped together (didn't know that before replacement). After finishing up, I started the truck to move it back to its parking spot and was only running on battery voltage. I removed the breaker from the equation and connected both cables on either side of it to the same post with no change. I thought that the 3G alternator or regulator had suddenly decided to die after almost a year (or less?), so I replaced that. New reman alternator had an actual Motorcraft regulator on it. Truck seemed to charge better (14V at idle) until the next time it left the driveway. It wouldn't charge over 14V. I fought with this for a bit until I heard belt squeal, tightened the belt and all seemed normal. So I got new belts (also Duralast, same as the old) and put them on right after it stopped charging again with no change. At that moment, I revved the engine up to about 3K and it started charging. Research indicates that the alternator/regulator aren't self-exciting, but will kick on when reaching threshold speed to excite. Still not sure why 2 alternators suddenly decided to no longer self-excite.
Today when we left the house to pickup our Hyundai from the stealership service center, it seemed week (13.9-14V at any engine speed). After getting the car, the truck just refused to charge, no matter what. I took the breaker out of the equation again with no change. I started at the stealership at 12.4V and was at 12.1V when I got home (cracked the window a few inches then rolled back up later and radio was on with volume off).
I don't understand what's going on here, or why this is suddenly an issue rearing its head after swapping to 6.0L GP harnesses. I've made sure I didn't touch anything else on the GP controller (but I do remember removing the large nut and one smaller one from it and reinstalling them). I even pulled the engine harness connector apart again to make sure that wasn't causing problems and it's still packed with dielectric grease from when I did the Molasses Carnage Corrections. Am I missing something, or do I need an exorcist?
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