Noisy Bachmann Standard 4MT 4-6-0

[RFS]

I have a problem with this model which is the later non-split-chassis version. It's 31-117 75074 and is DCC-fitted with a Lenz Standard+ decoder.

 

When it runs above mid-speed (in DCC terms about speed step 75) it starts to emit a loud whining sound, and this occurs in both directions on both straight and curved track. Using light oil (Peco version) I've carefully lubricated all the appropriate parts, including the gear wheels from the top and from underneath. But it all makes not a scrap of difference and I'm at a loss as to where the noise is coming from. The loco itself is extremely smooth at all speeds - no jerkiness, wobbling or such like. 

 

Any ideas?

[DCB]

It could be a pickup misaligned and rubbing with an edge instead of flat.  Not had it on Bachmann std 4 but on various Hornby and recently an Airfix Prairie. I use very thick oil on plastic gears  which mesh with brass. It's the residue out of cans of Wynns viscosity improver for car engines which you have to cut he can open to extract.  It's l free as I use it when I do oil changes with cheap oil and Wynns and I'm not doing too badly with 120K and 160K on two Rover engines with no work except a head gasket each.   Cheap discount Aldi oil is the stuff your dealer uses when he charges you £50 a gallon for the good stuff.

[RFS]

Have now at last found the problem. I decided to see if it was the motor by partially removing it so that was lifted clear of the gears and would thus run on its own. And indeed the noise was coming from the motor, or more precisely the motor bearings. A small drop of oil in the bearings at each end resulted silence.  I've not had that type of problem before, but thankfully easy to fix in the end.