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Alternator options for an 1800S

matt b

Active member
Joined
Apr 12, 2007
Location
Tucson
Wiring isn't my strong point and I want to be careful not to melt wires here.

B18 in a 63 1800S, with stock wiring. Currently running a generator but I need to switch to an alternator due to exhaust constraints (long story).

What are my options ? I can't find much when I search.

I would prefer to run an alternator that allows me to retain my current, brand new external voltage regulator and doesn't require wiring mods. That way, if the next owner wants to go back to stock: it would be easier. I have the bracket from IPD to run an alternator and can also weld up whatever I would need.

I have 3 wires running to my generator, one of which being just a ground.
 
I'm curious is you could get one of those Delco 1-wire alternators to work. Those have internal regulators, and just have a ground and one wire connecting to the battery positive.
 
I'm curious is you could get one of those Delco 1-wire alternators to work. Those have internal regulators, and just have a ground and one wire connecting to the battery positive.

One wire ones are easy to do, and I don't want to do that. I want to retain the charging light as a feature, for example.
 
One wire ones are easy to do, and I don't want to do that. I want to retain the charging light as a feature, for example.

I put a 3 wire GM alternator on my '63 PV, using a SWEM bracket.

1 wire to charge the battery
1 wire for the warning light
1 wire for the voltage reference - often just looped straight over to the first wire (output), but I ran a reference to the fuse block.

Just the bolt on bracket and some new wires. You can get new alternators just about anywhere that sells car parts, dirt cheap.

SH7zDj8h.jpg
 
Looks like I may have found an alternator here, supposedly compatible with a B18 or B20. It doesn't fit the existing mounting hole for an alternator on the block (sits too far forward), but I have a bracket I can use.

<a data-flickr-embed="true" href="https://www.flickr.com/photos/exim-cars/50662427786/in/dateposted-public/" title="IMG_9822"><img src="https://live.staticflickr.com/65535/50662427786_c771fe9371_z.jpg" width="640" height="480" alt="IMG_9822"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

How do I wire this up ? It's hard to out into words how much I dislike wiring, it's not my strong points and I always worry about melting parts.

Hard to read but the purple wire says EXC (exciter ?) and red says S. Bolt in bottom right hand corner says E, which I'm assuming is my ground since it makes contact with the case.

I also hope this alternator will cut power to my coil after I turn off the ignition, I'm guessing this is what this sticker means:

<a data-flickr-embed="true" href="https://www.flickr.com/photos/exim-cars/50662519832/in/dateposted-public/" title="IMG_9825"><img src="https://live.staticflickr.com/65535/50662519832_8979365d6a_z.jpg" width="640" height="480" alt="IMG_9825"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>
 
Exciter wire goes to the warning light. Red wire goes to bat positive terminal.

The ignition switch needs to cut the power to the coil, the alternator shouldn't have a choice in the matter, if it does you have some very iffy wiring going on.
 
Exciter wire goes to the warning light. Red wire goes to bat positive terminal.

The ignition switch needs to cut the power to the coil, the alternator shouldn't have a choice in the matter, if it does you have some very iffy wiring going on.

Thank you! Wiring is perfect on this car, so not worried about the ignition coil.

Hopefully I can finally run this car this week, it's been one delay after another these past 2 weeks.
 
I will say that there is convenience with the SWEM/Delco setup. My car had a custom fabricated bracket and delco alternator when I bought it. For once I was able to just go grab something from the parts store same day.
 
I ended up at my local generator/starter/alternator repair shop (Luna Industries) and asked them to tell me how to wire it. Red needs to be hooked up to the post with the black diode on top of it (reads 250V) and EXC is my switched wire. Issue was then how to bypass the voltage regulator in a clean fashion (appearance matters on this car) and that was more of a pain than it needed to be.

So I took the easy way out, the one that doesn't interfere with the car's current wiring, etc... I just installed a 1 wire alternator, I knew those units well and Luna had one on the shelf. All current wires are capped and can be used if someone wants to run a generator in the car at some point. They would just need to run a regular exhaust manifold instead of VP's 4-2-1 unit.
 
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