Whats the gauge of the circuit wire and the gauge of the fusible link?

Do you have an amp clamp meter to measure the charging current?

George

 

12 gauge (as per the wiring diagram and it looks like it). But we have two 12 gauge wires feeding into the fusible link which is the way it appears in the wiring diagram.

fusible link is 16G as per packaging

no amp clamp meter.

 

Its getting hot with only the alternator connected to the circuit?

How long is the fusible link?

Whats that voltage drop on either side of the link piercing the permanent circuit wire?


George

 

I wish that these wiring diagrams would annotate the proper fusible link values so that we dont have to guess, especially when a link feeds more than one circuit leg.

George

 

see above in red. Do you think I should give both D and E each their own fusible links to connect to the junction block?

 

Did some digging on your wiring gauges but the pickins' are slim and as usual much of the internet chatter is talking from its ****. It looks like the standard setup for your truck was probably a 10 gauge alternator charging wire with a 14 gauge fusible link if the alternator is still the original 63 amp model and everything is stock. Many forums talk about an upgrade to a CS130 model which has considerably higher output and needs a much heavier wire. That fusible link that you removed is marked 1.0 sq mm which is a 16 gauge fusible link. The question is was that original? A 10 gauge wire is already undersized based on some average amperage windage calculations. You can measure the diameter of the wire conductors with some insulation pulled back if you have a dial caliper. 10 gauge should be .102". I also saw a reference for a gm spec of the day allowing up to 0.5V drop from the alternator to the battery which seems high to me. Bottom line is not sure what to make of all this but a 12 gauge charging wire seems small.


George

 

i am pretty sure I have a caliper, but have not seen it in 8 years. Will try to find it. Why would all the wiring diagrams I have seen show 12G for wire D?

the alternator should have identifying information on it to be able to look up charging amps.

I may just run in for 20 minutes to see if the fusible link burns up. And remember, it started out 0.47V drop (pos-pos), but once the wire was hot, it was 0.64V.

if the alternator is oversized, then D itself should be getting warm, correct?

 

And I forgot to thank you for looking all that up and helping me in general with this

 

I missed a wiring diagram with reference to wire gauge on D, where do we see that?

Thats why we need to measure the voltage drop across that temp repair to see how much of the 0.5v is there.

Are both red wires on the alternator the same gauge? D is the wire on the output post, right?

What about the gauges on the other wires on that junction block?

Before this is all over I may recommend a minor wiring change. The three different diagrams have different approaches and what you have makes the least amount of sense.

Your welcome.


George

 

The existing wiring scheme has problems or at least is not ideal. Example: the full output of the alternator can go back to the junction block and head out on E all unfused. More modern wiring doesn’t use a scheme like this, the alternator output goes more directly to the battery and power is distributed from there.


George