Looks like a simple cutout relay there on the genny. Make sure the genny and the relay (via its mount to the genny which should be
grounded ???) have good solid grounds and the belt is tight. Just in case the ammeter is bad or stuck not showing charge it may or may not
still be charging. When running at fast RPM a working charging system should raise battery voltage to at least 6.5 to 7 on a 6 volt or 13
to 14 on a 12 volt, is it ?????????
Click on my Troubleshooting procedure below for step by step methods to see if non charging is due to the genny itself orrrrrrr the relay
etc. In Para 5 it shows how to MOTOR TEST the genny alone to see if its the problem, if it passes BOTH tests its likely okay.
On many of the old manual light switch type Low High Charge controllers that used a Cutout Relay (like you have) if they dont charge its
because the Low High switch ISNT WELL GROUNDED orrrrrr is bad orrrrrrr the wire from FLD post on the genny (NOT one to cutout) up to the
switch is bad/broke/open
See if it charges if you jump the gennys FLD post (NOT one to cutout relay) to ground ?????????? If so but NOT otherwise the switch is bad
or not grounded or the wire from FLD to Low High charge switch is bad/open........
Tighten the Belt,,,,,,, Polarize the genny (see my procedure),,,,,,,,, Insure Genny and Cutout Relay have good grounds,,,,,,,,,, insure
switch has a good ground and is wired down to FLD post on genny,,,,,,,,,,,,,,,,, try to ground the gennys FLD post,,,,,,,,,, Work my
Troubleshooting Procedure for cutout relay style systems..............
Best I have to offer over the net
https://www.yesterdaystractors.com/cgi-bin/viewit.cgi?bd=ttalk&th=2060825
John T
John Ts Charging Troubleshooting