(quoted from post at 06:55:02 05/28/18) A '51 8N would indicate an angle-mount distributor thus the generator was moved to the LH side of engine. Before we begin, I need to ask you if the generator is original with the correct belt tensioning device connected? I often see generators not charging simply because there is no belt tensioner on to keep the belt tight so it charges correctly as the part/device is missing altogether. Problem: battery not charging. Let's start with the battery. How old and what type? It should be a good GP-1 type, 6V AG style, not a deep cycle or RV/golf cart type and at least 550-650 CCA. It must sustain a full charge under load, specific gravity can be checked with a cheap hydrometer or just take it to your local starter shop or auto parts store, and they will bench test it on their special test equipment. Avoid bargain house batteries as well. They have short life spans, like 2 years average or less, and can be junk out the door. Invest in a good brand like INTERSTATE, DEKA, or EXIDE. Good brands often last at least 5 years, some double that. Now, a 6-volt battery installed does indicate that everything else is right. If it is not wired correctly you will have non-starting/non-charging/non-running issues. Your ammeter may or may not be faulty. I suggest you take your battery, the generator, and the ammeter to your trusty local starter/alternator shop guy who knows old Ford stuff and get them tested. He can also test your VR, starter, key switch and coil, but no need to jump ahead just yet. The VR could be included in the first group, but starter, coil, and key switch are moot since you say it runs now albeit poorly, and they are not part of the charging system. While shop is testing the components, get out your copy of WIRING PICTOGRAMS by JMOR and go thru the wiring exactly to match your tractor setup. Don't guess, don't go by wire harness colors -verify with a continuity tester or a multi-meter set to continuity. Don't take shortcuts from how it is supposed to be wired nor skip steps. If the wiring is a cobbled up rats nest, with electrical tape splices all over, trash it and invest in a new harness. The problem is the generator isn't charging the battery. Now you must determine the root cause and which part of the equation needs to be solved. When you get to the root cause and problem solved, many here use a Battery Tender, see Bruce(VA)'s '75 Tips For N-Owners', to maintain their batteries with a full charge when not in use. We will discuss the virtues once you get back running...
Tim Daley(MI)