On my 1950 F-2 V-8 I have an odd part that was just hanging free off my oil pressure sending unit. It looks like a capacitor but the outside is insulated and I don't see any wire coming off to complete the circuit. I can't figure out its purpose. The Ford parts manual seems to show it (see red arrow) but that is the only reference to it that I can see. Does anyone know what it is and where I can get a new one? Is it critical?

 

That would serve as an electrical noise suppressor and to smooth the action of the OP gauge. It electrically 'dampened' the electrical 'noise' of the oil pressure switch. Not critical.

 

Correct, Ray, but it is the "noise" of the generator cutting in/out at idle speeds. With a gen, the voltage drops to battery voltage as soon as RPM drops down below ~700 or so. It also puts a big spike into the system whenever the cutout relay opens/closes. All the gauges will suddenly drop when when the cutout opens, so Ford went to great lengths to dampen the system. The capacitor stores enough energy to reduce the drop for a while.

BTW I threw mine away a long time ago.

 

Thanks guys. That helps. How was yours grounded Ross? I may have a bracket missing? Since I now have a single wire alternator that should lessen the impact. We'll see when I get the gauges running. I don't know how long it has been since they were powered up but I had them apart and they look fine. I did find the horn wire hooked to the temp gauge and that wire has been cut out near the radiator for a long time or at least long enough for the metal core to turn black.

Thanks again

 

I can't remember how it was mounted exactly, but it was right on the sender unit, maybe with a clamp?

 

With a one wire alt. you won't have a need for it .

 

There's a circular type bracket on the back of the gauge (upper left-hand corner) where the suppressor would be inserted and held.

 

If you're talking about the loop in the red circle, that's the inductive pickup for the amp gauge. The only thing that should be in that is a wire.