[Farmall] Turning on the magneto switch on Farmall "H"

[Mike Sloane]

The quickest check would be to put a voltmeter between the "BAT" 
terminal on the alternator (or the positive battery terminal) and 
ground. If the alternator is working properly the reading should be 
between 13.5 and 14 volts when the engine is running. If it is not 
working, the voltage will be something less and slowly dropping as the 
ignition system slowly drains the battery.

My experience with converting old Farmall tractors to alternator 
operation has been that you need to put the smallest pulley you can find 
on the alternator, as the high idle speed 1600-1800 rpm of those old 
engines isn't really fast enough for proper operation with the standard 
pulley that usually comes with the alternator. Most auto parts places 
have a carton behind the counter somewhere with a bunch of different 
used alternator pulleys in them. You have to dig through them to find 
the one you need (i.e. about 2" in diameter that fits your alternator 
and matches the contour of your belt). A decent auto parts place will 
help you out, but what you find at the average chain (like AutoZone) is 
that the counter help barely know how to spell "car", and if you say 
that the alternator is for a tractor, you will get the "deer in the 
headlights" look. (Been there, done that) You can also try a automobile 
salvage yard for a smaller pulley - at least the guys there will have a 
pretty good idea of what you are looking for and why. Removing the 
pulley on an alternator, by the way, is a little tricky, as there is no 
good way to hold the pulley without risking damage to it - the quickest 
and easiest way is to use an impact wrench.

Mike

Tim Savelle wrote:
> Thanks.  And also....is there any way to tell if the alternator is charging
> the battery?  The amp meter doesn't move off zero when I flip the toggle
> switch up and down.
>