# Having trouble with this loco, DC short circuit. EMD GP35



## Michaeld4502 (Feb 26, 2018)

ILLINOIS CENTRAL EMD GP35 DIESEL Loco

From the photos number one end bogie shorts against the frame. The red wire was a round the screw on the bogie at the top. I'm unsure of where to attach the wire or if been modified or not.
I bought the loco 2nd hand. I'm not sure what brand it is either & haven't been able to locate a drawing or picture of the body removed. 
Maybe Ahearn ??
Would anyone have the parts list please ?
Would anyone have this loco and post pics of their loco with body removed. Thanks you.


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## gunrunnerjohn (Nov 10, 2010)

Your post was moderated for some reason, I released it.


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## T-Man (May 16, 2008)

On HO engines the trucks wheels are insulated by rail location ( side to side. One rail is going to give power to the motor, right OK which side is that?

Your red wire comes directly off a motor brush and goes to the other truck.

That means the motor truck is supplying power to the other brush.

The red wire is grounding the second brush to the opposite side of the track at the other truck.

The circuit is track, wheel, axle, brush, 2nd brush, red wire to other truck and axle wheel and other track.

Now is the other truck insulated from the frame? WiIth the screw as shown apparently not. That means if a short is present it is at the motor side between the wheel and the first brush without the red wire


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## T-Man (May 16, 2008)

If you want to have fun, Using your two transformer wires, disconnect the red wire touch one wire to the other brush and one wire to the brush with the disconnected wire. 

If it runs your short is on the first brush side to the wheels and not your red wire side. I think the red wire side is connected to the other truck and the frame ,but I cannot tell from the pictures.

For parts you need to go HO seeker . org and review the HO diagrams until you find your engine. It maybe an old Athern.


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## Dennis461 (Jan 5, 2018)

OP,
You say it shorts against the frame.
Does it work ok on straight track?
What radius curves do you have.


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## DonR (Oct 18, 2012)

I do not know this loco.

Athearn does not list a GP35.

The shell looks very similar to my Bachmann GP30s
however the innards are not the same.

The most common diesel wheels to motor wiring
has a red wire from the right side wheels to one
tab of the motor and a black wire from the left side wheels
to the other. That may not be the system on this loco.

Let's hope a member recognizes this loco as one he has and
can provide accurate suggestions.

In the meantime you can do some tests.

From your post it may be that the front truck passes
the right side wheel connection thru that 'screw'. And
the left side wheels connect thru the frame.

You can disconnect the motor and use your multimeter
set to ohms to determine if that is correct.

If so the red wire goes from the screw to one motor tab and there should be a physical connection from the other motor tab to the frame. Somehow there should be a red wire to
the light circuit and it also would need a contact to the frame.

If the bottom comes off of the trucks you
can check the wheel wipers and how they send power
to the motor.

To locate the short check for any contact of the red wire
circuit to the frame. (other than through the motor)

It may be that the presence of 8 brass wheels indicates
all wheel power pickup. If so there should be a red
wire from each truck and a black wire from each
truck. (or that the left wheel current is passed through
the frame). 

Let us know what you find.

Don


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## T-Man (May 16, 2008)

Just by luck I spotted hobby town. this is very close to what you have except it does not have the dual flywheels. I looked at the GP 3o and two engine kits.


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## Michaeld4502 (Feb 26, 2018)

Thanks all, I had a look at the hobbytown locos and I think this is the manufacture as it is very close to some of them, I reattached the red wire to the top of the bogie screw. 
I ran the loco and when it goes around the curve it shorts to frame, even tripped the overload in the transformer unit. It works fine on the straight, although a little noisy.
My solution is to file out part of the frame and also remove some of the bogie. 
Seems odd though this would have been doing this at manufacture. Was hobbytown a expensive, good brand ??


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## T-Man (May 16, 2008)

Increase the clearance by grinding is best.Aa little electrical tape would not hurt either. From the picture a cross member must be your insulation from the frame.

I can't tell you anything about the company the pamphlet said they were Boston based. Glad to hear all is well :thumbsup:


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