smokebox

Or the way its wired.

I've no idea. The symptoms you describe are very odd, so anything's possible.

The only thing I can think is that the loco may be drawing more current than the decoder can handle. Unusual symptoms though.

How are you powering the cdu?

You may need to wind the wire around a former or mandrel slightly smaller than the axle to allow for spring back when tension is released

I use graphite powder which I bought online for for my door locks. Extremely fine powder that goes everywhere if you are not careful. Absolutely brilliant for pinpoints as it doesn't attract dust or attack plastic like oil can.

You can report this thread and ask for it to be moved to the correct section.

Whoops!

Looks as if the decoder is plugged in the wrong way round. The orange wire should go to pin1 not 8

That info may be out of date now. Refer to the list on the Hornby site which gives the latest, up to date recommendations. It was found that some of the earlier suggested power supplies were causing problems.

Cleaning and oiling may well help.

A friend of mine used it to repair a hole in his cars thermostat housing, lasted for years. The original Araldite is the best I've used. The 5 minute stuff is OK for less demanding jobs.

Speaker Watts is how much power they can accept.

Motor control is not usually regarded to be a function.

A meter is virtually essential. You will almost certainly need it again and again. A simple one which is good enough for model railway use can be bought for £10 or even less.