MTH Rotary Beacon

Depends on what model beacon you have! Earlier versions worked off of the bulbs' heat (they have little fins built into the top of the beacon for the heat to make them rotate). The newer ones have a vibrator builtin the base of the lamp to make them rotate.

I have the vibrator type and trying to figure if there is another reason for the vibrator to stop at the same time the light goes out besides some break in the power connection. 

@BobHoward posted:

My MTH Rotary Beacon stopped working - no light, no rotation.   Pretty sure it is getting power but it's in a difficult to get to spot on the layout.   When the bulb burns out, does the rotation stop?

No, the bulb is not in series with the vibration coil (AKA motor).

So even if the bulb did burn out, more likely answer is you lost power to the entire unit.

After inspecting mine, I might see a possible way it could fail. The common (not really ground) is the entire stamped metal tower, which has folded contacts from the base to the tower, from the top of the tower to the top metal plate. and then again to both the coil and the light fixture. So one side is proper wire- in fact individual wires for both the coil and another for the light, however, the return path is through folded metal tab connections that are painted.

So yes, quite a few places this could go wrong.

The white covered wire is the coil wire, the black wire also to the same terminal is the light.

The other side has no wires, and it basically making connection to the red metal stamped baseplate. That in turn must make connection to the silver painted tower folded tabs.

Then at the top, we have the same problem, the tower silver folded tabs touch the red painted metal top plate, and then the black metal folded tabs are making that other side of the connection to the red metal plate.

It's not clear to me from your description whether the beacon just stopped turning or the vibrator stopped working. Apparently it had been working previously, so that seems to indicate that it's not electrical connection problem, particularly if the new bulb works. If the beacon just stopped turning, join the club. These rotary beacons (both MTH and Lionel - have used them both) have always been problematic, at least for me. It's difficult to keep the beacon assembly turning  reliably for any period of time.

(BTW, the old types that worked off the bulb heat haven't been made for many decades, and never by MTH - they were last made by Lionel before MTH came into existence.)

@freon posted:

Depends on what model beacon you have! Earlier versions worked off of the bulbs' heat (they have little fins built into the top of the beacon for the heat to make them rotate). The newer ones have a vibrator builtin the base of the lamp to make them rotate.

I didn’t know MTH made the bulb heat version. I thought MTH was strictly vibramotor.
Steve

@RideTheRails posted:

I didn’t know MTH made the bulb heat version. I thought MTH was strictly vibramotor.
Steve

See the post immediately above yours. 

I have 2 of the MTH beacons that are powered by thermal currents. 

@RideTheRails posted:

I didn’t know MTH made the bulb heat version. I thought MTH was strictly vibramotor.
Steve

They didn't.  Why would they go through the same 'learning curve' that Lionel did in going from the 394 to 494 mechanics??  The dimpled bulb 'heater' and fragile beacon top were as finicky as they come.  (3656 bovines a close second!!) 

Replacing the rubber finger washer is usually the most effective way to restore rotation.  They're very available from various parts purveyors.  They're easy/fast to install.  I keep several on hand.

If the finger washer is new and the mating parts clean, you should find that rotation will be very good at lower voltages.  However, as the finger washer wears, the fingers shorten, wear debris builds up, it'll take a higher voltage to get rotation.  When the fingers are really worn out (I've repaired some that literally have NO finger remnants whatsoever!), it's time for overhaul...at any voltage!!

The vibramotor is a decent, simple, easy to maintain way to get motion.  Lionel learned how to employ it quite well...IMHO, of course.

Sounds like yours may be an electrical discontinuity issue, though.

KD

They have problems transmitting the ground from the top of the tower to the base due to too much paint.  When I worked at MTH I threaded a lacquered wire up the tube, fished it out the hole in the tube, soldered it to one of the tabs for the coil and to the ground lug in the base.

My ERROR. I totally missed the MTH in front of the question. Sorry about that one.