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I thought I would post my findings that it may help some one in the future. Voltage went high on my MEP-003A, 160+ VAC. Hz reading was correct but I had no control over the voltage using the voltage adjust and % load meter and voltage meter were not working. My initial thought was bad voltage regulator so I swapped it with a known good one, no change. So with a friendly thrashing from triple-jim I went through the manual for high voltage troubleshooting. It all checked out good until I got to the CVT1, the control winding section showed ohms out of spec. Of course that sucker is buried deep and wrapped in wire like no tomorrow.
I was able to locate a new CVT1 on ebay for $40 so when it arrived I started to dig out the old one. Manual says to unbolt phase/voltage switch, then remove bolts holding CT and CVT1 in place, tag wires and remove, easier said than done. I unbolted the switch, this gives you enough play to disconnect 3 wires on it, the other 3 wires are removed from the terminal board on the back. Once these 6 wires are disconnected you can pull them through the ct's, then unscrew the wires from the top of them and then remove the ct's. The CVT1 was cracked and actually split open pretty bad. The CT was actually in minty condition and tested ok. Assemble in reverse order, and check for any loose connections, now is the time. So this is when I discovered that the wire going from L3 to the main breaker was burnt at the breaker connection, it was loose and of course making some serious heat. Green mv helped me out here and supplied a new breaker and a used wire to make the repair. The stud on the breaker was damaged and the area around it was damaged from the heat so I wanted to play it safe and replace the breaker. The manual says to replace it through the side opening but it's much easier working on it from the top, just remove the top cover and terminal lug board.
I also had a lazy starter and it would grind on the ring gear 50% of the time so while in repair mode I pulled the starter and replaced the solenoid with a new one. A vendor on ebay had them new for $40 in military packaging. Fired it up and all is well, no more grinding starter and 120VAC, back in business. Big thanks to triple jim and green mv for all their help.
I was able to locate a new CVT1 on ebay for $40 so when it arrived I started to dig out the old one. Manual says to unbolt phase/voltage switch, then remove bolts holding CT and CVT1 in place, tag wires and remove, easier said than done. I unbolted the switch, this gives you enough play to disconnect 3 wires on it, the other 3 wires are removed from the terminal board on the back. Once these 6 wires are disconnected you can pull them through the ct's, then unscrew the wires from the top of them and then remove the ct's. The CVT1 was cracked and actually split open pretty bad. The CT was actually in minty condition and tested ok. Assemble in reverse order, and check for any loose connections, now is the time. So this is when I discovered that the wire going from L3 to the main breaker was burnt at the breaker connection, it was loose and of course making some serious heat. Green mv helped me out here and supplied a new breaker and a used wire to make the repair. The stud on the breaker was damaged and the area around it was damaged from the heat so I wanted to play it safe and replace the breaker. The manual says to replace it through the side opening but it's much easier working on it from the top, just remove the top cover and terminal lug board.
I also had a lazy starter and it would grind on the ring gear 50% of the time so while in repair mode I pulled the starter and replaced the solenoid with a new one. A vendor on ebay had them new for $40 in military packaging. Fired it up and all is well, no more grinding starter and 120VAC, back in business. Big thanks to triple jim and green mv for all their help.
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