i am powering a dummy atlas 2 rail gp9 using atlas 2 rail gp35 guts. i am confused as when i put the power trucks in the gp9 the plunger pickups are on opposite sides of one another. is this correct? i hooked it up to the qsi board from the gp35 and its shorting out. the atlas parts diagrams are confusing to me. any help is much appreciated.
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How did the trucks sit in the GP35? I don't have either unit, but I have a set of the Atlas FMs and I think the plungers should all be on one side. I think the other side power pickup is through the truck/body chassis.
I believe only the wheelsets on one side are insulated.
Hi Alco
Ok as I recall you cannot mix the gp-35 and GP-9 because the mounting plates are shaped slightly different. There is a plastic insulating mounting plate that fits on top of the metal one and it needs to be there or else the engine will short out. Its also important to use the engine mounting screws with the plastic washers as a final layer of protection against a short. Yes, the pickups for the GP-9 are on opposite sides and the GP-35's have pickups on the same side. I wire these engines in series so I have to use a different wiring configuration. I will sketch something out for you if you are interested in trying this.
With all of that said, I think you could file off the mounting tabs on the plastic insulating plate and drill some fresh holes into the frame to bypass the difference in shape of the GP9 mounting plate. I never got that far.....there were enough Gp-9's floating around on Ebay a few years ago to just buy a powered unit and make the switch.
Email me dsmith041@maine.rr.com if you have further questions......
Don
hello. thanks for the replies, the gp9 does have different bolster plates. the plastic pads between the metal plate and frame are present. the gears were on the same side on both trucks when on the gp35. mounted up on the gp9 the gears are on opposite sides. would i just need to rewire the loco so each side is only connected?. coming from ho and n these mechanisms are a bit wacky to me. any wiring pics would be much welcome. regards, dan.
The GP9's I have (very early) didn't use the plunger pickups. The each truck picked up power from one rail. This was later changed when the trucks were modified with the plunger pickups.
The trucks were isolated from the frame.
If you have the wires connected to each truck the same as they were on the GP35, I assume you just need to reverse the wires on one truck.
the trucks i have are the plunger type. i should tinker with it some more. i ll try to wire it for dc instead of dcc . the qsi decoder does not sound good anyway.
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