Installed GM AC Delco 12SI

[Northoffrisco]

After much thought about this I decided to install a GM AC Delco 12SI over the weekend after having charging in the past. Before I did this I went and replace the VR to see if that was a the cause, then I chased down the wiring in the fuse block to see if I had a loose connection, then I pulled the oe alternator and had it tested, and.... the alternator was bad, I did a lot of reading and asked a lot of questions before I decided to change this over, but in the end I think I made the right decision to do this, I did have to modify the adjustment bracket but was able to keep the stock belt on it, I also was able to put back on the shroud in front of the the alternator,
the wiring was a little different but was able to to some what figure it out, I will be putting in a vm gauge very soon just did not have one laying around. I did remove the vr completely and kept it en tacked just in case I need to go back to it, I did have to clip one wire which is a ground jumper, but grounded it to the nearest location
I can now charge the battery at idle which is giving me 14.69v
all my lights work dash works everything but the passenger side tail lamp but that didnt work before, it does work if the lights are on but does not light when the lights are off
so there has to be some issue going on that I will look into later
I also replaced the ignition switch which was going bad, and now when the key is turned to the (H) position it does heat the glow plugs, I will be replacing the wiring on that as well to a bigger gauge
Here are few pictures of the alternator installed
thanks again

 

[Bob Rooks]

Ignore the charge light. I hope your alternator doesn't overheat because of the belt guard. The air flow on these alternators is the reverse of OEM TEFC alternators. You also have your sense line connected to the output terminal. Sorry.

 

[cleat]

I would also tape up or shrink wrap the ends of the cables to prevent shorts if the wire moves a bit.

Cleat

 

[Bob Rooks]

I also replaced the ignition switch which was going bad, and now when the key is turned to the (H) position it does heat the glow plugs, I will be replacing the wiring on that as well to a bigger gauge.

Did you replace the key switch (no ignition on diesels) with a new OEM or identical replacement?
Most folks would install a small 40 amp relay in the glow plug circuit to keep the current draw through the key switch to a minimum.

 

[Rich Waugh]

It looks good for the most part, but I'd recommend removing the belt guard as it may cause the Delco alternator to overheat by blocking the flow of air through it. As Bob sys, if you really want to improve the glow plug wiring add a relay so the key switch is only handling about 1 or 2 amps for the relay coil and the relay contacts handle th eload of the glow plugs. Use 10 gauge wire from the battery /alternator to the relay contacts and from there to the glow plug buss bar and the OEM wiring will handle the primary relay coil just fine.

 

[Northoffrisco]

thanks for the advise
I did tape up the extra wires and they are out of the way, also was thinking about the belt guard too, I just might remove it, I have the 10 gauge wire for the glow plugs and I should be installing that in the weeks to come and I will for sure add a relay for the glow plugs,

 

[Northoffrisco]

one last thing I did replace the em ignition with a new oe one
I had a diode installed to the key switch running from the alternator to the key switch

 

[Bob Rooks]

I had a diode installed to the key switch running from the alternator to the key switch

Um, why?