Jump start oops

[velojym]

Just hook up one half of a jumper cable one end to your pos on your battery and one end to the back of your alt and check the gauge to see if the voltage gauge in your truck moves up a little.
Doing this bypasses the fusible link and wire leading to your starter.
If the voltage increases replace the wire and fusible link.

Yeah, that'd be a simpler way to do what I've been wringing myself out over.
and... yeah. I'd gotten used to having a decent multimeter handy, and it kinda threw me for a loop when mine started acting up. I'm gonna check the leads (if/when I get a minute to myself) and, hopefully, that's all that's wrong with it. I do have a cheap one packed up in the basement somewhere. I'll dig it out if I can.

[velojym]

Kicking myself in the head for not thinking of it, but I'm going to need the wire I put together anyway. I used the jumper cable.

Pre-cable, I was reading battery voltage on the in-cab gauge.
With the engine running...

With the cable connected to the alternator and the battery, I'm showing a nice bit over the 13 mark. I nearly got excited enough to get the truck up on jacks so I could get under and install my new wire, but my arthritic joints told me to wait a bit, as the weather's gonna warm up in the next few days.

[Irish_Alley]

what did you do to fix the charging problem

[velojym]

what did you do to fix the charging problem

Haven't fixed yet, just diagnosed. I bypassed the wire leading from the alternator to the starter with a jumper cable, and found the truck getting full charge voltage. Since the starter is getting juice from the main battery cable, I've made a replacement fusible link/wire to replace the one from the alt to the starter.

[velojym]

Ack. Forgot to post. I ran the new wire, and drove Earl down the road a bit, and found that my voltage was changing with engine rpms, from battery voltage up to around 16v. I'm guessing there's a voltage regulator problem there, and also... the battery is bad. I topped it off with a charger, and it'll be flat within three days or so.
Not sure if the regulator in this truck is part of the alternator, whether I can replace it without having to replace the whole alternator.... my repair manual shows how to take the thing apart, so I'm guessing I can if I need to.
I'll pick up a new battery when I get this part figured out.

[78 Chevyrado]

Yes the regulator is inside the alt.  Only special tool required to take apart the alternator and put it back together is a paperclip or something similar to hold the brushes in place while you put it back together.

[velojym]

I guess the alternator's part number should get me the one for the regulator I need?

[jaredts]

Do what you like but I wouldn't risk changing the regulator.  Just take the alternator to a parts store and have it tested.  If it tests bad buy a new one.  If it tests good go over all of your grounds and connections.

[1980c10]

check the cost of an altenator; you may find it cheap enough that you don't want to go through the trouble of installing the voltage regulator

[87454westernhauler]

i would recoment just geting a new alternator. they are cheep and usually have a waranty on them and then u know that it is right.

[velojym]

I'm going into town tomorrow for some stuff. I'll pull Earl's alternator and take it with me, get it tested, and I'll just replace it if bad. The ones in these trucks are as cheap as they come, and you're right. I'll be a lot more comfortable if I know the part's history.
Same will go with the battery.

[1980c10]

If possible get everything squared away at the same time; stress in a starting system tends to cause more problems. For example you need to repair wiring, replace your battery and alt. All of those parts did not fail on their own. With this in mind, when you do this work make sure your connections/cables are all clean tight and in good condition. That way everything stays healthy.

[bake74]

If possible get everything squared away at the same time; stress in a starting system tends to cause more problems. For example you need to repair wiring, replace your battery and alt. All of those parts did not fail on their own. With this in mind, when you do this work make sure your connections/cables are all clean tight and in good condition. That way everything stays healthy.

     Dominoes anybody ?   

[velojym]

If possible get everything squared away at the same time; stress in a starting system tends to cause more problems. For example you need to repair wiring, replace your battery and alt. All of those parts did not fail on their own. With this in mind, when you do this work make sure your connections/cables are all clean tight and in good condition. That way everything stays healthy.

     Dominoes anybody ?   

That's exactly what I was thinking. I started out just looking at the most obvious problem, the fusible link by the junction block... and after fixing that, I've chased it all the way back to the alternator and battery.
I'm not even going to crank this truck until I get all that squared away. The P.O. was a P.O.S. ...at least insofar as working on my truck was concerned.

[Skunksmash]

Who's name is Earl? The truck?