Not-Charging Frustration

[Cubey]

However more likely is that the sense wire to the regulator has a bad connection or cracked or something and isn't telling the regulator to "turn on".

The springy plastic clip part of the two wire connector at the alternator is weak/bad on my RV. It tends to wiggle out from engine vibration, causing the alternator to shut off. I was able to put a small zip tie around the plastic connector to hold it firmly into the alternator.

The connector isn't too expensive though:
https://www.ebay.com/itm/ALTERNATOR...RD-LINCOLN-MERCURY-1G-LARGE-CASE/181705691905

The zip tie thing has worked nicely since I couldn't sit around waiting for a connector when the problem popped up. It has held up even after pulling the alternator and putting it back for replacing the fan clutch. I should probably order one to keep on hand, but in a emergency, crimp on insulated blade connectors would work, so long as I don't mix up which wire is which. The zip tie is working for now so I see no reason to fix what's working. A big piece of gorilla tape would hold the connector down too, in a pinch.

 

[IDIBRONCO]

You said the gauge was low when running but did not list the charging voltage from the multimeter; could you update with that?

The first post said 10.5 volts on the factory gauge and 12.5 with the DVOM.

 

[Philip1]

You must be registered for see images attach

here is a wiring diagram of the 3g alternator

 

[The_Josh_Bear]

The first post said 10.5 volts on the factory gauge and 12.5 with the DVOM.

Doh. I read that wrong thinking it was standing voltage.

While we are at it, anybody know how to make the stock gauge accurate? Thing drives me nuts being off so badly. No sense having one like that!

 

[IDIBRONCO]

My totally not serious answer would be to paint the whole thing black so you can't see it. Maybe cover it up with duct tape?

 

[franklin2]

Doh. I read that wrong thinking it was standing voltage.

While we are at it, anybody know how to make the stock gauge accurate? Thing drives me nuts being off so badly. No sense having one like that!

Remember the volt gauge in the dash is reading the voltage in the dash wiring. Not unusual to have a 2 volt drop in the wiring from the battery to the dash wiring.

 

[stick_witch]

Yeah I agree, stock volt gauge in the dash is garbage and should not be paid much attention to. If you want a voltage reading from inside the cab, get a 12v cig plugin voltage meter, or even better, wire in your own straight off the batteries... or EVEN BETTER, use a multimeter... as far as making the stock gauge work accurately, I honestly think its a lost cause, I imagine you would would just end up butchering the cluster wiring, and even if you got it to work, the quality of the gauge itself isn't really that great... it's a dummy gauge... just ignore it, or make it disappear, or maybe get creative and make it into a fun meter or something.

 

[IDIBRONCO]

Remember the volt gauge in the dash is reading the voltage in the dash wiring. Not unusual to have a 2 volt drop in the wiring from the battery to the dash wiring.

Yep. I was trying to put a voltmeter on my 1983 Goldwing today. I found out that it drops 1.5 volts between direct to the battery to where I was wanting to get it installed.

If you want a voltage reading from inside the cab, get a 12v cig plugin voltage meter,

This is what I've done. The plug in meter reads .1 volts less than a DVOM on the battery while the engine is running. That's close enough to being accurate for me.

 

[The_Josh_Bear]

Yeah I agree, stock volt gauge in the dash is garbage and should not be paid much attention to. If you want a voltage reading from inside the cab, get a 12v cig plugin voltage meter, or even better, wire in your own straight off the batteries... or EVEN BETTER, use a multimeter... as far as making the stock gauge work accurately, I honestly think its a lost cause, I imagine you would would just end up butchering the cluster wiring, and even if you got it to work, the quality of the gauge itself isn't really that great... it's a dummy gauge... just ignore it, or make it disappear, or maybe get creative and make it into a fun meter or something.

Lol fun meter!

 

[IDIBRONCO]

Lol fun meter!

Just write "fun" on the instrument cluster over the voltmeter. then all you have to do is figure out some way to make it peg out when ever you have the truck running. That way, the "fun meter" is always pegged while you're using the truck.

 

[IDIBRONCO]

Just write "fun" on the instrument cluster over the voltmeter. then all you have to do is figure out some way to make it peg out when ever you have the truck running. That way, the "fun meter" is always pegged while you're using the truck.

Better yet: mark out the word "boost" on your boost gauge and write "fun" over it instead! Now I may try this one on my truck.

 

[stick_witch]

Just write "fun" on the instrument cluster over the voltmeter. then all you have to do is figure out some way to make it peg out when ever you have the truck running. That way, the "fun meter" is always pegged while you're using the truck.

Hahaha yeah thats what I'm thinking. Maybe if you connected both batteries in series on a closed circuit of 14 gauge wired directly to the meter you could get it to peg to 24v?

 

[stick_witch]

Better yet: mark out the word "boost" on your boost gauge and write "fun" over it instead! Now I may try this one on my truck.

A boost gauge is kinda the equivalent of a fun meter already

 

[IDIBRONCO]

A boost gauge is kinda the equivalent of a fun meter already

But it's more fun than a voltmeter.

 

[idi_econoline]

One battery bad or not, your engine-on charging situation is totally separate.
You said the gauge was low when running but did not list the charging voltage from the multimeter; could you update with that?

Also a new alt doesn't guarantee that the new regulator is working correctly. However more likely is that the sense wire to the regulator has a bad connection or cracked or something and isn't telling the regulator to "turn on". This is the yellow/white stripe wire that goes to battery+. Grab that multimeter and do an ohm test on that wire, only takes a second to verify. You can also do a voltage test on it, same thing since it carries 12v all the time.

Voltage at batteries when running at above-idle same as idle. Was 12.something, not the 13+ I would expect with a functioning alternator.

Will hunt down that wire, thanks.