Ask Phil - Curing sticky point motors


Question: I have fitted Peco point motors to my layout and while most work perfectly, some seem "sticky". Any idea how to make them work properly? Chris, Watford.

Phil: Sticky, or lazy, point motors are very frustrating and can really ruin an operating session. When you press the button to make one work, having to check that the point has thrown properly is a pain.

I'm going to assume that your motors are fitted under the baseboard. If they are clipped to the bottom of the points, some of my suggestions won't be relevant, but will hopefully help someone else.

The problem is most likely to be that the motor needs a little adjustment. Try waggling it by hand - is it smooth or is there resistance? If the operating pin is rubbing on the side of a hole through the baseboard then it might not be able to overcome the friction.

Is the operating pin moving along the line of the tiebar, or at an angle to it? You might need to remove the motor and re-fit it.

The adaptor base has an over-centre spring fitted and, combined with the same spring in the point (I'm assuming Peco points, but others have a similar spring), this can prove too much for the motor. Take the spring out of one and it should move more easily.

Slacken the screws holding the adaptor base to the board slightly. It's easy to overtighten them, bending the plastic base a fraction and introducing friction into the system. I've used motors hanging off the bottom of the board by a couple of millimetres and, as long as the operating rod still connects with the tiebar, they work fine.

I show how to fit a point motor in this video:

Finally, fit a Capacitor Discharge Unit (CDU).

This device stores up electricity and releases it in one go when the point is activated - think of it as an old-fashioned turbo-charger in a car. Press the pedal and an extra boost is released in one go.

You only need a single CDU for your layout. Wire the point motors to the output and the input to a 16v AC supply.

I show how to wire a motor with a CDU in this video.

You'll need to fix one motor at a time, but fitting the CDU will certainly help. With one, you can even change several points at the same time with confidence.

Finally, don't stress about this - it happens to all of us. I can't remember a single layout I've built where at least one motor hasn't needed some "tweaking" to make it work properly.