Lionel crossing gate

I'm guessing there's some missing/chipped teeth on one of the plastic gears.

I've not seen the design of the Lionel 5-wire gate, but I have opened up the MTH 5-wire gate which I'm guessing is a similar design.  A DC can motor lifts/lowers the arm thru a multi-stage gear train. 

So when trying to lift the arm, when the flat spot is reached (arrow in diagram), the arm drops down from gravity.  Then the gear transmission re-engages and lifts the arm for a bit...then flat spot is reached again and arm drops from gravity.  Lather-rinse-repeat.\

If it's practical to operate the gate upside-down, I'll bet you can get the arm to go to the "up" position...if that makes sense!

If you can perform surgery on the patient and expose the gear/transmission, my guess is you'll find a mechanical anomaly on one of the gears.

Again, I'm not familiar with the Lionel design, but on the MTH 5-wire gate, it is a well known issue with a plastic gear cracking/breaking thereby causing slippage and unsatisfactory behavior particularly in the going-up motion.

Thanks, Stan. Micro surgery may be in order, and then the issue of trying to get parts. 

Things were simpler in the fifties with the oval on the ping pong table.

Yup.  The crossing gate is at that price-point where it's a coin toss as to trying to repair it or simply removing the arms and turning it into a flashing-only signal.  See this OGR thread about the MTH 5-wire crossing gate.

In any case, my "offer" as in the linked thread applies.  If you reach a stopping point or can't find replacement part(s), if you ship it to me I will volunteer my time to do a tear-down on the Lionel version and publish the results with photos etc. on OGR.  This is simply to support the hobby.

I know the Lionel product has a worm gear assembly. Does anyone know what's involved with getting a look at it and replacing it if necessary? If not too bad, that part is available from Lionel.

Thanks Stan. I'll be back in town next week to start the investigation!

I discuss repair of this item in the link below:

https://ogrforum.com/...2#145297443299905522

Thank you.

This OGR thread also has some nuggets of info.

Would be interesting to see close-up photos if practical of damaged part... maybe a candidate for a 3-D printer.

Here are some close of pics of a crossing arm that I removed for a repair.  This worm gear is slightly damaged.  The worm (not shown) was fine and was able to be reused.  The white nylon worm gear is the weak link.  It is indexed on the square shaft that is also indexed to the gate.  There are bushing on either side of the gearbox to allow rotation.  One would have to drive the square shaft through from one side to recover the worm gear. 

The worm gear is available from Lionel, but the white gear is not.

I'll visually inspect the white nylon gear and if it's okay, I suppose my issue is with the available worm gear.

The worm gear (white nylon) Is the weak link.   Makes sense that this part is no longer available.  Lionel recognized the design flaw and created Series 2 to eliminate the worm and worm gear.