I just did one for a customer .... and initially - with it sitting on the bench in front of me - I was uncertain how to approach it !
Each truck is grounded to its corresponding half of the split frame as is the motor. The first step was to isolate the motor from the frame halves. This involved totally dis-assembly of the two frame halves to get the motor out. The contact wipers on the motor (that contact the frame halves) were then trimmed off and small wires soldered to the remaining tab. Reinstall the motor running the two new wires up through the slot above the motor between the two frame halves. Work carefully - it's a snug fit - you don't want to pinch a wire so it grounds to the frame again.
You can use whatever decoder you want - I used a TCS A4X attached to the top of the chassis with double-sided tape. Attach the two new motor wires to the motor terminals on the decoder.
To pick up the track power, I drilled and tapped a hole in the top of each frame half and inserted a small brass screw. A wire was then attached to each screw and fed to the track input on the decoder.
Done !
Mark.
¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ
Only ones I ever saw were still sealed in their boxes, never run, and both had a big chip out of the paint on the side of the cab. Very wierd. I opened one up and took off the shell to see about DCC install and thought better of it. Bachmann seems all over the place with their quality, some Spectrum models are absolutely incredible, others are little removed from the old cheapy train set quality Bachmann stuff - yet it all has the Spectrum label. It's hit or miss - IMO the GP30's are in the 'miss' category.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Greg Shindledecker Modeling the =WM= Thomas Sub in the mid-70s
I've got three. It's a slip on fit only pick up by the fuel tank.
Wayne
How much trouble is it to put the shell on a athearn or pk2 or kato?
I have a couple. The original drives are less than premium. Looks like a scaled-up N-scale engine, with the split frame, and the truck pivots way up high. I found them to have excessive slop and bucking coming down a 4 percent grade.
I re-powered my pair with Athearn GP35 drives.
You could pick up one the newer GP30s from Bachmann, with the decoder already installed. You would lose the flywheels, though.
It depends if you like the engine enough.
The P2K GP30 is better all-around, shell detail and running quality. Some guys have put Kato GP35 mechanisms under them.
Mike WSOR engineer | HO scale since 1988 | Visit our club www.WCGandyDancers.com
I have a circa 1990 HO Bachmann Spectrum GP30 that I am considering converting to DCC. Reviewing comments shows that it should be trashed. Has anyone done a conversion? Thanks.