Powermate 8kW non AVR generator low output bad capacitor in endbell

Non AVR generator. AC Exciter winding goes to two diodes and feeds about 150 volts DC to the Field brushes in this 8kW generator if correct. But this unit had a bad capacitor, but two good diodes. The 130uF 200 volt capacitor is across the two brushes. The two diodes are 1N2160 600 volts 40 amps. The cap measured about 25uF with a B&K Precison 875 LCR meter, ie a capacitor tester. The nominal 120 volts AC output of one leg was really about 108 to 110 volts with a small 1500 watt load.