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Discussion Boards => HO => Topic started by: leofuture on September 29, 2017, 08:25:19 PM



Title: 2-8-0 disengaged
Post by: leofuture on September 29, 2017, 08:25:19 PM
The wheels won't turn but will turn fine when I press the chassis with the bottom of engine, it seems that the worm gear box doesn't engage fully with the gear on the 3rd wheelset. I already tighten the screws but still.. Is there anyway to fix it? Thanks!

I did the following tests--

- wheels do not turn freely, so it seems the main drive gears are fine
- belt and worm spins fine when chassis is dissembled from the driver set
- One plastic separator between the 2 split metals is missing one leg, but I was able to screw in the hole



Title: Re: 2-8-0 disengaged
Post by: jonathan on September 30, 2017, 05:01:49 AM
When the first spectrum 2-8-0s came out, there was a problem with the split casting. The space that holds the bushings for the worm gear axle was not cast completely. So, the worm would not seat properly to the drive gear.

Years ago there was a guy who showed how to make larger bushings from brass tube. You can search this forum for Jim Banner, but I don't know if that thread still exists. There weren't many connies that had this issue I believe it was just the first run, anyway.

If you can wiggle the worm gear around, that's your problem.

Regards,

Jonathan


Title: Re: 2-8-0 disengaged
Post by: Len on September 30, 2017, 05:38:33 AM
Found it in my, "You might need this info some day.", archive:

Quote
Title: Re: 2-8-0 grinding noise
Post by: Jim Banner on November 06, 2009, 09:52:30 PM
I have never seen a belt wear out in a Spectrum Consolidation (but it is possible.)  What I have seen is worn out bearings on the jack shaft.  This is the shaft that the belt runs to and also has the worm gear mounted on it.  The bushings, one on each end, are about the size of a wedding ring for a mouse.  And once the brass wears through, the shaft cuts quickly into the soft metal used for the frames.

It is possible to replace these bushings with new ones made of pieces of brass tubing.  Cut the tubing as long as will fit and deburr the ends.  Set the bushings into a cleaned and degreased frame, using a tiny bit of epoxy to hold them in place in the worn cavities.  You can keep the epoxy from getting between the shaft and your new bushings by using gear oil or light grease between the two.  Install both bushings and the shaft at the same time so that the shaft can keep the bushing aligned.

If you use a tiny drop of light oil on each end of the jack shaft every 50 hours or so, these bushings will outlast the originals.

Jim

Len


Title: Re: 2-8-0 disengaged
Post by: leofuture on September 30, 2017, 12:10:01 PM
Thanks! I don't understand this one "If you can wiggle the worm gear around, that's your problem." it doesn't wiggle when chassis & wheel base are together, but wiggles when separate


Title: Re: 2-8-0 disengaged
Post by: RAILSPLITTER on October 22, 2017, 08:17:34 PM
Should not wiggle at all it is a fixed gear that has to mesh up its teeth properly with another at a precise depth called gear lash.Too loose or too tight of a mesh and you get abnormal gear teeth wear and noise. Correct mesh and it is smooth and quiet. Hope this helps your understanding.

Jon