Locomotive Shop
Proto 2000 FA and FB 1624
Reworking a Proto 2000 FA and FB from around 2002 that had operated for at least 5 years.
Last week a club member dropped off a pair of locomotives, one FA and one FB for service. These were early Proto 2000 locomotives known for issues with their 4-wheel trucks having gears that cracked weather used or brand new in the box. In this case both had an eight pin DCC decoder plugged into the lighting board. Upon evaluating the locos ran poorly but better in reverse.
Each of the decoders had pin one in the pin eight position. Correcting this allowed the locos to run in the correct direction however I demonstrated the ability of changing the direction by setting the first bit in CV29. After correcting the installation of the decoders, the locos still ran poorly and the lighting on the FA was only working a dim headlight. Each locomotive had, in addition to a lighting board above the motor, a light control board in the rear of the loco. This board was factory installed for DC operation of the FA to have headlight and Mars light effects as the loco moved forward. The reverse installation of the eight pin DCC plug caused an issue with the 2-filament lamp in the Mars light location. Without today’s controllers the Mars light effect used a lamp with 2-filaments alternating to provide the effect. All the connections on the locomotives were using press fittings with covers and not soldered.
I decided to remove all the electronics from both locomotives but keep the decoders which were NCE102SR with eight pin plugs. I reinstalled the decoders by wiring the connections to the track and motors in the FB and included LED connections to LEDs installed in place of the incandesce lamps. I directly soldered these connections to the decoders after removing the eight pin wires.
The oiginal lights
Programming the decoders with the NCE Power Cab and JMRI allowed me to create the correct direction and lighting effects on the FA, there are no lights on the FB. The FA’s decoder yellow wire driver no longer operated, so I used the green FX1 wire for the Mars light, setting the correct bits in the effects and control CVs.
The next issue was the replacement of the gears in the 4-wheel trucks. I found that one of the wheel sets was not an original factory gear in a truck and did not replace that gear as the wheels were solid on the gear. Testing of the locos showed that the FB did not run as well as the FA. Because the shells were off each at this time, I could observe the motor operation on each and their response to the same power.
The FB had been out of service long enough for the grease to harden in the worm gears and as it turned out also in the upper gear in the truck towers. Cleaning the worm gears and replacing them improved the operation but did not clear up problems with the starting voltage. I began to investigate this by disconnecting the worm gears to look at the operation of the motor. I found the motors to operate at low starting voltage.
I started to investigate the trucks. Each had deposits of factory gear grease. I cleaned each side of the gear box and each gear. After assembly, the gears ran freely, but with assembly of the trucks I found the truck with only one wheel gear I had installed caused a binding in the operations of the gears. I replaced the last gear, and this resolved the binding of the gear train.
Assembling the locomotives and operating both on the layout after slight lubrication the locos ran well together, with the lighting operating on the FA. Small adjustments of the CV2 on the FB provided final operation.
After this the final assembly and five or six runs around my layout with the two locos two feet apart, I setup a consist and pulled a 30-car freight train around the layout for about an hour.
Four gears on the wheel sets and 2 LED were the only parts needed to repair these fine-looking FA and FB units. Extra parts after the repair went into the spare parts box. The work on these units, was finding the issues that prevented these locos from operating together.
A side note the locomotives were both numbered 1624. I renumbered the FB as 1625, also the FB has the “F”, for front, printed on the wrong end.
Return to the Locomotive Workshop (Click Here)
Work Shop Home (Click Here)
Join us in the “Greatest Hobby” as a member of the TLMRC.
Site home (Click Here)