What's new
By:
Filters
Old Chevelles

Welcome to OldChevelles.com, built by Auto Enthusiasts for Auto Enthusiasts. Cars are not our only interests so please feel free to post about any subject the community might enjoy or you just feel you need to air.

We respect free speech and constructive dialogue however we don't allow threatening talk against members, nudity, or pornography. Threads are monitored and trolls are not tolerated.

This site is completely free and there are no costs. Please enjoy and provide feedback.

  • We've enabled the website app for anyone who wants to use it on a mobile or desktop device.

  • We've changed the header logo to display our Member's Cars.

    If you'd like your car to show up there, go to the forum Site Bugs & Feature Requests and post your image in the "Member's Car Pictures for the Header Logo" and we'll add your car into the lineup.

Quite possibly a very stupid ammeter question

J

JohnC

Veteran Member
Senior Member
The C10 has an issue where the ammeter doesn’t seem to work very well. It’s stays centered and deflect only minimally. It also seems to move the wrong direction. If I rev the engine the needle moves slightly toward discharge. My Dad replaced the gauge at one point. Not sure the issue with the original but perhaps true same thing.

I checked the two fuses on the core support and they’re good.
Regarding the needle seemingly moving the wrong direction it’s not possible to simple swap wires because the gauge is fed by one of those flexible circuit boards deals.

I asked my Dad about it and he seems to remember the problem seemed to start many years ago when the alternator voltage regulator stopped working and he replaced the alt with an internally regulated single wire alt. Not sure if this has anything to do with it.

Is there anyway to bench test an ammeter? See if the gauge moves as it should?

Thanks
 
Someone can correct me if I'm wrong, but I suspect the gauge was tied to the external voltage regulator.
 
Have you checked voltage at the battery while it's running and give a few light revs to see if voltage increases?
 
Chevelle_Nut said:
Wired backwards? If it is charging and showing discharge this is a possibility.
Click to expand...

"Regarding the needle seemingly moving the wrong direction it’s not possible to simple swap wires because the gauge is fed by one of those flexible circuit boards deals."

Unless it was wired wrong under the hood (not likely) it can't be wired backwards. His father went from an external regulator type to a single wire alternator (like you just installed on your tractor), so it no longer goes through the external regulator which is why I suspect the lead to power the ammeter came from the external regulator.
 
kmakar said:
"Regarding the needle seemingly moving the wrong direction it’s not possible to simple swap wires because the gauge is fed by one of those flexible circuit boards deals."

Unless it was wired wrong under the hood (not likely) it can't be wired backwards. His father went from an external regulator type to a single wire alternator (like you just installed on your tractor), so it no longer goes through the external regulator which is why I suspect the lead to power the ammeter came from the external regulator.
Click to expand...
Anything is possible, I have run into strange stuff. After so many years and many people working on things stuff just can be flat done wrong.
 
Chevelle_Nut said:
Anything is possible, I have run into strange stuff. After so many years and many people working on things stuff just can be flat done wrong.
Click to expand...

I wasn't arguing with you Jon, but based on what John said, I didn't see that as the problem, but since neither of us can see it directly, neither of us can say with a certainty. Anything is possible.
 
kmakar said:
I wasn't arguing with you Jon, but based on what John said, I didn't see that as the problem, but since neither of us can see it directly, neither of us can say with a certainty. Anything is possible.
Click to expand...
It is amazing some of the hackery. Being a C10, depending on year, electronics could be minimal, who knows maybe a wrong gauge was installed.
 
Thanks folks. I’ll check to see whether the ammeter is fed from the external voltage regulator.

I’ll also check the battery voltage when the engine is rev’d

I’m pretty sure he got the ammeter from LMC so it should be the right one.

It’s a pretty unmolested truck. There no hackery of the wiring harness.
 
Well a little internet search confirms this is almost certainly an issue created by the single wire alternator. I’m the kind of person who if it’s on my car I want it to work even if it’s not really necessary. Problem is I haven’t found a “fix” that I’m confident in. Most threads are “yup, that’s your problem. Why do you want an ammeter anyway? They’re worthless.” Oh well. Maybe I’ll put the Malibus alternator in the truck and go back to externally regulated.
 
Good call. The ammeter will have to be wired differently and possibly replaced with a 1 wire alternator. The 3 wire alternator with an external voltage regulator will feed a wire to the stock ammeter.
 
I’d go with a newer type electronic ext regulator But if you want a new in the box point type you can have the new (a cpl yr sitting in a tool box) just pay post office, I mailed a 30 lb convertor yesterday and was $46.26 so I’m guessing under $10 in a Post Office small box
 
JohnC said:
Nice offer. I’ll have to check mine. It might be that the voltage regulator isn’t even bad.
Thanks
Click to expand...
I was having dimming/ bright light issues after I put a Load Boss 135 amp 3 wire alt on my car so I called Load Boss and the owner told me I needed an electronic ext reg with their alternators so I did that and no more problems, my under dash volt gauge bounced a lot before the electronic reg too
 
You must log in or register to reply here.
Top Bottom