Skip to content
View in the app

A better way to browse. Learn more.

Ultimate Subaru Message Board

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.

100A Alt Swap Question

Featured Replies

Just got done doing the Hitachi-toGM alt swap as described here: http://random.removed.us/altswap.html

 

The alternator I got was off a 1982 Caddy. Here's my question. One of the two wires (the field signal wire) from the caddy's two pronged plug was tied back onto the output stud. Why did they do that? When I tie into my wiring harness does it make a difference if I simply eliminate that re-feed and go directly to my field signal wire, or should I leave that GM wire tie back into the output stud and splice my field wire into that?

 

I test ran it without the wire looped back into the stud and it seems to be charging steady at 14+ volts.

One of the two wires (the field signal wire) from the caddy's two pronged plug was tied back onto the output stud. Why did they do that? When I tie into my wiring harness does it make a difference if I simply eliminate that re-feed and go directly to my field signal wire, or should I leave that GM wire tie back into the output stud and splice my field wire into that?

 

They did that to eliminate the field circuit (and the charge indicator lamp). By tying it back into the output they made the alt self-exciting (the output see's 12v from the battery when the alt is not making power). This way they didn't have to rev the engine past 3k to get the alt to self-excite.

 

GD

Please sign in to comment

You will be able to leave a comment after signing in

Sign In Now

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.