wjones

Ive been getting the self-resetting breakers from here:
http://order.waytekwire.com/scategory/M37/140/250
they also have the buss bars and brackets:
http://order.waytekwire.com/scategory/M37/140/50

apwatson50

Nice site, thanks for sharing, its much cheaper than napa!!

apwatson50

So i've gotten a few miles on this alternator now, and it seems to be working great! Well the battery hasn't gone dead so it must be working. haha

But now to my only unresolved issue. The check engine light is on, and i'm assuming its because of the open circuit created by not having the stock alternator installed. There are 2 smaller ~12ga wires that come from the wire harness to the stock ALT. I've figured out that one is power from the ASD relay, and the other is the control wire from the PCM.

So how or what would I need to do to this wiring to make the PCM think the ALT is there and charging?

Thanks, Aaron

Ace

I'd guess maybe the PCM is not getting a voltage on one of these pins:

http://dens-site.net/Dodge_CTD/1991....ams/Scan38.jpg

#3? Who knows?

You could always try just jumping 12v (or maybe ground?) one or both of those field wired I believe they are called and check results. But results could be a blown PCM or worse, for all I know.

Don't do anything on my advice. Somebody that knows alternator wiring/charging systems better than me should reply.

apwatson50

Yeah already tried that, didn't blow anything up, but the light also didn't go out.

I was thinking that if the PCM saw voltage on its control circuit then it would be happy. However I didn't leave the power to that wire for very long, while running I hooked it up, light didn't go out so I unhooked it. It might work but just need to cycle the key or something?

I was hoping an electrical genius would just tell me to do this... and all would be right in the world again.

Aaron

Alec

I know that this install is pretty old news, but after Aaron did his, I bought a reman 160 amp alternator for cheap . . . This weekend I finally got around to putting it on the truck. So my thanks to Jim & Aaron for their pioneering!

As I have a manual IC'd truck, I could do it a little differently, to make more room for the tensioner and the intake hose. I cut the mount of the thermostat housing, and moved it to from the side to the top of the housing, by contouring the cut-off and brazing it in the new location.



I didn't really like relying on that long 3/8 bolt & all those spacers to locate the rear mounting ear on the alternator, but I didn't want to take the bracket/coolant inlet assembly apart. I realized that the hole in the bracket was just shy of the drill size for 1/2" UNC, so I chased the hole with a 27/64 drill bit (I did this by hand with a pair of pliers, I barely had to remove any material), and tapped it through. This allowed me to use a long fully threaded mounting bolt.



A couple of Jamb nuts to hold the rear ear.



Tightened the front ear to the mount with the bolt, then the rear nut, then the center jamb nut.



As the bottom bolt is still pretty weak, I wanted to make sure that the top arm provided good rigidity and support the alternator against the tension of the belt.



And here's a final shot.



By the way, I'm using the K080845HD Gates belt, which is in stock & cheap at Rock Auto.

j_martin

I think if you put a 25 ohm, 10 watt resistor between the wires, the PCM would be happy.