Ammeters Model A vs. Model T
 

Does anyone have good pictures of the front and back of a Model T ammeter?

Since the Model T is negative ground, I assume the ammeter was different than an A, in that the magnet may be flipped so the needle moves the opposite direction.

Anyone know an easy way to spot an A ammeter from a T ammeter? Thanks

Re: Ammeters Model A vs. Model T
 

The magnet could be flipped or the wires just reversed.

Re: Ammeters Model A vs. Model T
 

The 26-27 ammeter is the same as a model A, except the bezel is flat instead of ribbed. I have some but getting a photo to this computer is a pain. The earlier T ammeters are about twice the size.

Re: Ammeters Model A vs. Model T
 

Tom, I found this online - Not sure if it's OEM but does appear to be NOS

Re: Ammeters Model A vs. Model T
 

In addition I believe the model T ammeter had Ford on the face plate,?, where the A did not.

Re: Ammeters Model A vs. Model T
 

...and Ford sold a spacer ring so the late ammeter could be used as the service part for older T's.

Re: Ammeters Model A vs. Model T
 

Repros...

Re: Ammeters Model A vs. Model T
 

I thought the Model T one has the FORD Script.

Re: Ammeters Model A vs. Model T
 

The meter used in the T era did have Ford script on it, maybe the very early A's also (?). The meter does not care if - or + ground as long as the wires are hooked up the correct way for the system.

Re: Ammeters Model A vs. Model T
 

Repro, as Brent said. You can even see the brass through the window. Model A's had flat black paint over the brass.

Re: Ammeters Model A vs. Model T
 

Tom, you do have my curiosity up when you wrote that comment regarding the magnet and the polarity of the ground. Care to expound on this??

Re: Ammeters Model A vs. Model T
 

This appears to be a nice original ammeter for the Model A, but the owner wanted me to flip the magnet so the yellow battery power wire would connect to the left post, the one closest to the center of the car. This way it would match up with the wiring diagram.

The magnet is very tight to the case, so removing it and installing it takes a lot of care to not damage the needle.

Re: Ammeters Model A vs. Model T
 

I have seen original Ford A and T ammeters with the magnets installed both ways. I supposed that they have been worked on many times down through the years and some people just put the magnet back in without checking it. The original wire on a original 28-29 dash lamp is very short and will only fit on the closest ammeter terminal without stretching it very tight. I always turn the magnet so that the terminal closest to the dash lamp is the load side. I find ammeters at swap meets with black bezels and other than the black paint they look like the ones with the chrome bezels inside and outside. The mounting tabs on the original bezels are usually broke or will break when you mount them, so I usually install new reproduction chrome bezels on them.

Re: Ammeters Model A vs. Model T
 

The Model T is negative ground versus positive ground for the Model A. An original Model A ammeter installed in a Model T will run backwards. This is same for a Model T ammeter installed in a Model A. The magnet poles are reversed. The bezels on the Model T are flat.

Re: Ammeters Model A vs. Model T
 

All you have to do is swap the wires.

Re: Ammeters Model A vs. Model T
 

Ammeter's Model A, mid 30's V8 and USA made replacement with Ford script, i didn't want to take the cover off to show magnet placement in replacement. Best I can tell is the Model A is original and it reads opposite of the V8. V8 and replacement read the same.

Re: Ammeters Model A vs. Model T
 

and one more of the backs;

Re: Ammeters Model A vs. Model T
 

The cheap repro's I've seen didn't have a magnet.

Re: Ammeters Model A vs. Model T
 

The magnet on the one I got from Bratton's is part of the needle assembly.

Re: Ammeters Model A vs. Model T
 

I looked best I could thru the opening, I could not see a magnet around the inside of the case on the replacement.