SD-70 - AZL

There are some other issues with the AZL SD's that Robert Ray discovered. They drive the axle worm gear through a flexible plastic tube. This is not always perfectly 'slid' on the motor shaft or worm gear, creating a sort of binding. More significant it seems is the worm gear bushings are swivelling balls with through holes. These are held in place by a black plastic block. The block has a tapered shape and fits tight into the motor halves. It appears that this compresses enough to hold the brass bushing too tight so it does not freely move with the gear flexing.

Jeff Merrill reports that he has filed them down (removed the taper) so that it fits more freely in the motor halves. He got about a 30% speed improvement with a bit less current demand. Rob got at least a 50% improvement.


Dom wanted to fit an MT coupler to the front of his loco, this is what he did:

Cut truck's coupler arm with some dykes.
Install a new pilot AZL part # 61099-5 in place between shell's fwd lateral stairs. Will take some filing.
Remove snowplow, pulls off forwards.
Unscrew and remove existing AZL coupler box.
Screw in new MTL #905 coupler.
Cut the original snowplow from its pilot.
Glue the original snowplow on the new pilot, making sure there is no interference to the MTL coupler components.

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