Amp meter at idle (1 Viewer)

[SteadiCruiser]

74 amp meter on newly built up truck and just wanted to confirm if this idling level and behavior is normal or showing an issue.

 

[Steamer]

Your voltage regulator is basically a three-position switch and it's possible yours is rapidly switching between two positions. You could read up on Rudy’s thread “HERE” and adjust it or you could just get a new one and see if that settles it down.

I bought two aftermarket VRs from CCOT for my 74 and both of them charged extra high and required tweaking. If I still had and external regulator I would go OEM from a vendor here like Toyota Matt.

EDIT: You could also take the cover off the regulator and move the contacts with something non-conductive like a toothpick to hold them in each of the positions to see if it steadies the ammeter. You could also get your alternator tested.

 

[Skreddy]

I second @Steamer recommendation on if you buy a new VR. I got 2 through Napa and both charged high: up to 16 volts. It will cost more but worth it to get one from Toyota Matt.

 

[SteadiCruiser]

Thanks guys.

Always happy to get something good from Matt.

Here's an old pic from when the regulator was installed.

To be honest I don't recall where it came from.

I can probably just yank it off to get a better look but does this look like aftermarket to you?

Thanks again.

 

[sterling]

I went with a Toyota factory remanufactured regulator.
OEM piece, priced reasonably and still available.
Good luck!

 

[KennyBob]

To tag onto this discussion, I also went with a toyota reman'd regulator on my '66 and my amp meter still jumps around like that. Only way I've found to calm it is to turn on some accessories such as the lights.

 

[Skreddy]

My guess is that VR is probably aftermarket but I can’t confirm for sure. My original had a metal cover and both aftermarket’s had the black plastic cover with a generic part number on it.

I got high charging (or real low) with the aftermarket but still got the bouncing as well unless something was on creating a steady draw like heater fan or running lights. Condition/charge of your battery will also impact that bouncing or total amp draw as well.

 

[pb4ugo]

Have you checked what the voltage is at the battery when it's running?

 

[Living in the Past]

Have you checked what the voltage is at the battery when it's running?

This was my first thought. Was the battery new and fully charged to start with. What happens when the RPM is raised. Running voltage at the battery in the whole process.

 

[SteadiCruiser]

Really appreciate the input and education guys.

I'll check battery voltage tomorrow.

However for a bit of context, it's a new alternator and battery installed by a reputable vendor but I've had a few battery drains due to some wiring issues creating multiple parasitic draws over the past few weeks finishing up the truck and wiring harness.

I am worried that I might have done the battery in over the past few weeks of running down and recharging.

I did notice this evening (with my first joy ride around the neighborhood since getting the truck running) that the running lights were pulsing to the rhythm of the amp meter jumps.

Could that be an indicator of a specific condition or problem?

 

[SteadiCruiser]

Just an update that after testing almost every connection I discovered that the new regulator had a defect on one of the three male pins in the connector where the pin's locking tab had gotten bent all the way forward allowing it to be pushed back into the connector when joined with the other plug.

Just goes to show that sometimes you have to check EVERYTHING.

Still a little squirrely sometimes but overall seems to be stable and charging (or at least not discharging) the battery.

Thanks to everybody for guiding me through the most mysterious and least understood (at least for me) part of this truck build.

Michael