inconsitant reverse running

[Sylvian Tennant]

I have just been cleaning out and test running some old chassis for a future project. (Specifically two old 94xx wth three pole armatures and a 57xx with a five pole armature).

When running the two 94xx have preformed as a good as can be but the 57xx chassis struggles with switching direction. Also when running in reverse it will preform well for about 5 minutes then gradually slows to a stop. This is a problem as reverse running and shunting maneuvers would be a requirement for my layout.

All models were dismantled and cleaned with airbrush cleaner (being told it was less offensive to the plastic and electronics) and reassembled and all of the parts were accounted for. The gear of the 57xx is plastic but doesn't look damaged and the mess seems to be correct.

Can someone offer any advice to this predicament.

[34theletterbetweenB&D]

Is the motor of the 57xx hot when it slows to a halt after 5 minutes in reverse, but remains cool indefinitely running forwards?

 

If so, some mechanical problem (missing thrust bearing in the motor, binding in the gear train in reverse direction, etc.) is indicated.

[DCB]

Are we talking Grafar N Gauge here.  

[The Johnster]

One directional problems can be down to several things, but ultimately suggests a mechanical problem.  Check that the motion is not binding in one direction and overheating the motor by removing the motor and pushing the chassis in both directions to ensure that it runs equally freely in both.  Check that the worm gear does sit down on or rise up off the cog in one direction, and check that nothing is 'unidirectionally' fouling; you will probably be able to hear this if it is happening.  

 

If none of that isolates the problem, ask again!

[Sylvian Tennant]

Are we talking Grafar N Gauge here

About 2000 era garfar.

Edited February 10, 2018 by Sylvian Tennant