Need help with MTH Aquarium car slipping it's gear.

Can't see your video. But both MTH and Lionel aquarium cars are notorious for slipping gears in my experience. Not much you can do other than clean and oil it.

Thanks Train Nut.  I was afraid you were gonna say that.  Not sure what happened with the video, but it's obviously not needed.  I can't imagine the gears wearing out after only 2-3 years, but something is changing in there.  Too bad, 'cause they are really eye-catching cars.

I will contact MTH service.  I read in a 2015 OGR post that MTH is aware of the problem and may have a fix.  We'll see...

Jerry

If the gearbox is not engaging with the spool, the gearbox is mounted on some grommets that if overtightened will misalign the drive gear with the spool.  In some cases the idler gear can be slid back to increase tension on the belt.  One issue on older versions is that the ink on the backdrop reacts with the belt and causes it to stick.  Pushing the backdrop back a little and securing it with tape, plus adding a little talcum powder between the belt and backdrop will help.

Jon G,

Thanks for the reply, but, nope.  The problem has nothing to do with the backdrop or the belt.  It is clearly that the gears are slipping.  If I push the gear drum forward 1/8 inch, the problem ceases.  Of course, that cannot be maintained if I re-assemble the car.

Jerry