Anyone have any experience installing a Digitrax DZ 125 wired decoder in an N scale Kato SD 45 (pre-single light board)? I've converted seven locomotives with drop-in decoders and one with another DZ 125 - an Atlas GP 40. (Unfortunately, it quits running when I press the body shell down all the way). I've already sawed off a chunk of body frame under the cab but wonder about going through the fuel tank. Any tips would be greatly appreciated. Thanks.
I've installed 3 DZ125's recently on all non-DCC ready locos. A ConCor PA1, Lifelike FA1, and Lifelike GP 18.
On the Lifelike FA 1 I had a similar problem that you are experiencing on the Kato SD 45. It was a matter of:
1. Carving out more space for the gray wire where it passed around the motor.
2. Creating a deeper channel for the red and black wires.
Evidently, adding the body shell was enough to bind the motor to the point where it could not run.
If your SD 45 is split frame construction, try loosening the screws that hold it together and then put the shell back on. I did this with the FA1 and that kept the loco running, albeit the shell bulged. That's what lead me to make the 2 modifications above. It's one of my best running engines now.
I love DZ125's. I have a Kato GP 38 to convert still, also non-DCC ready. I know that it will take me every bit of 4 to 6 hours to complete the work, but well worth it in the end.
Here's a link to one that was done in the fuel tank using a TCS M1 decoder which is a similar size as the DZ125. Aztec cut the frame but the photos tell the story on where to cut. http://www.tcsdcc.com/public_html/Customer_Content/Installation_Pictures/N_Scale/Kato/SD40_non_DCC/SD40_non-DCC_M-1.html
I did 4 of mine years ago using DN93 decoders. They were 3-4 times the size of a DZ125. I cut the long hood end because there is more clearance over the rear flywheel. Installing under the cab would require cutting the flywheel down. that's a job only for a lathe and I didn't have one. You also need to cut a channel along the top of the frames for wires and a small groove to get one of the motor wires down to the lower brush. Take some material off around the brush caps too to make sure they stay isolated after attaching the gray and orange wires.
Personally, I think installing on top under the long hood is easier. Only one wire needs to be routed down to the lower motor brush. the rest stay up on top. Fuel tank install requires getting at least 5 wires up to the top.
Martin Myers