Hi there. My granddad recently got his old Ford 4000 repaired after the head gasket blew. He had the guy repairing it put in some new gauges(none of the old ones worked). The guy took out the original gauge panel, and put in an ugly piece of black plastic with only an oil pressure and engine temp gauge.
I'm intending to put the original gauge panel back in after making some modifications to it.
Anyway, my question is about the tachometer. The guy who worked on the tractor replaced the generator (which also didn't work) with an alternator, one made for a Chevy truck, I think.
Since the tractor doesn't have enough RPMs for the alt., he put a smaller pulley on it. Does anyone know if I can install a tach drive on this particular alt., and whether or not the RPM reading will be accurate, with the smaller pulley (which I think makes the alt. spin faster than the engine)
The alternator is a "Delco Remy BG" stamped with the numbers 21201118, and bearing a sticker with 7127SW3 on it. It is a single wire, and starts charging once the tractor is revved up one good time (it doesn't stop until the tractor is off, according to the "mechanic"). It has a built in charge regulator, which keeps it from overcharging the battery.
The tractor is a 68 model Ford 4000, 4 cylinder. And one other thing, I don't necessarily need an rpm log (the thing that looks like the mileage recorder in a car, or something like this: [000243420}).
What I want is a needle gauge that'll tell me my current RPM's.
I also want to know if the different sized pulley (different from what was on the generator), and by consequence, the alternator's differing speed from that of the engine, will have any effect on the accuracy of an RPM gauge (tachometer).
Any help is greatly appreciated, thanks in advance