alternator wiring

[RichLo]

Thanks, I just tried that on one of the informative posts, I think it worked!

 

[PlayingWithTBI]

that's similar but different Peter, those are your browser bookmark.

these are forum bookmarks... just like a browser bookmark but stored on the forum.

I think its a pretty cool feature that I did not notice before.

That is cool, I just like to look in one place for all of my internet bookmarks - sometimes I forget which forum I saw what from. That CRS kicking in from time to time

 

[GoToGuy]

That bookmark list looks alot like mine!

 

[scott2093]

Figured I'd park here...

Wanting to fix a pretty good voltage drop from my alternator to the battery junction block and other places on my 1993 Yukon. I'm getting 14.2v at alternator but a volt less everywhere else and as low as 10v at ac clutch....

Have some 4awg welding wire coming but am nervous about making sure I do it right and was hoping for direction. Just gets more confusing the more I read through threads and the fusible links I know are important.

The fusible link from the alternator to the junction melted in the past and this one's connector is burning up although it's just heat discoloration. I think the 8awg wire is either too small or maybe something else is up.
The battery positive fusible link to the junction box actually melted in the past as well but the replacement has been fine for many years afaik...

How would you go about upgrading this setup with some 4awg wire? I appreciate any advice.

 

[Schurkey]

4 gauge wire is suitable for starter motors. Enormously too heavy for most alternators. Consider 6- or perhaps even 8-gauge instead, somewhat depending on length of the wire and alternator rated output.

 

[454cid]

Start checking all the connections and figure out where its not making good contact. You shouldn't need an upgrade just to keep from melting things....unless maybe you've got some aftermarket devices pulling a lot more current.

 

[scott2093]

You shouldn't need an upgrade just to keep from melting things....unless maybe you've got some aftermarket devices pulling a lot more current.

Thanks. Nothing has melted in a long while. Just noticed that the yellow butt connector that I guess I used at the new fusible link maybe 5 or so years ago was browning in the center. Not sure why in the past I had issues with the fusible links and just wrote it off to ageing .
I suppose it's a bit of a catch 22 since a bit of a drop will cause more current draw but I don't have any after market accessories apart from headlight relays.
Hmm.. Not sure why I'd get a full 1 volt drop from the alternator to the junction block. Fusible link is only several inches and the rest is what I'm guessing is 8awg from alternator...
Alternator suspect? It has 14.2v at output iirc. Can they start giving up where the current output is involved. Can't even push enough through several feet of wire?

 

[454cid]

Thanks. Nothing has melted in a long while. Just noticed that the yellow butt connector that I guess I used at the new fusible link maybe 5 or so years ago was browning in the center. Not sure why in the past I had issues with the fusible links and just wrote it off to ageing .

Where is this yellow butt connector? I'm no wiring guru, but I suspect that's not the best thing to have in a fusible link.

 

[scott2093]

Where is this yellow butt connector? I'm no wiring guru, but I suspect that's not the best thing to have in a fusible link.

It was at the junction block section joining the fusible link to the 8awg wire coming from the alternator. I cut it off the other night and used another butt connector but it was some heavier duty one without plastic I had a stash of from an old lineman electrician who passed and I shrink tubed it. How are they supposed to be connected? Solder only?
It didn't solve my voltage drop but I haven't had a chance to start digging further. That would be great if it solves my issue but I would be happily surprised.
Thank you!

 

[scott2093]

I'm an idiot. Thanks 454cid ..... Connection at alternator output was loose. Tightened it back up and no voltage drop. Still not sure why I'm only getting 10v at the ac clutch when it's being activated. Maybe some janky wiring somewhere.

Also ,not sure why my meter at the battery reads 14.3 but the scanner says battery voltage is a volt less 13.2... I'm guessing that's normal from the drop in the wires that feed the computer? Or is the computer and scanner supposed to read the what's actually at the battery and I need to address this?