I think X04 motor

I have an old Hornby R059 Pannier that's never been out of the box, so I thought I'd have a go at fitting a decoder.

I found that right hand feed was by pick-ups on the wheels, but left hand feed is direct from the wheels via the axles with the whole chassis being 'live'.

I've made sure that the brushes are totally insulated, as is the right hand feed, & I've checked for no continuity, but as soon as I put the loco on the track I get a short.





Has any one ever done one of these?  Am I wasting my time?

Mal

The secret, as you have gatehered, is to insulate the wire spring that holds the brushes in place. One arm is already insulated and by insulating the other arm the motor brushes can be quickly and easily isolated from the chassis.



There are a number of ways to do this. You can cut the sleeving from the right-hand arm in half, use insulated sleeving stripped from a wire or heat shrink tubing.

Unsolder the red pick up wire from the right hand brush and connect it to the decoder’s red wire. Solder the decoder’s orange wire to the right hand brush.

The decoder’s grey wire needs to be soldered to the left hand brush. Finally the decoder’s black wire should be soldered to the tag on the motor retaining screw. The capacitor attached to the tag can be removed and the installation tested with a meter before you place the loco on the programming track.

Failing that - pay me to do it :lol:!

Mal your wiring looks right to me,and the insulation,check the decoder to make sure the short is not that end,
unlikely but worth a look,
you did mean "short" not "error" ? cos error is another kettle of fish.
lol::cool:

Thanks guys.

Ian - wired exactly as per.  At first I'd just used heat shrink on the brush spring, but thought that too thin so put insulation tape as well.

Owen - yes, I do mean 'short'.  You can actually hear a little 'crackle' as soon as the loco hits the rails.  I thought possibly faulty decoder, so tried another with the same result.  (The only other one I had was a Hornby & I wasn't at all impressed with it.  As soon as I removed it from the packet, two wires fell off right at the decoder & I had to resolder).

Back to the drawing board!

Mal

I would try unsoldering the red decoder wire from the green pickup wires and try again. If you still get a short, then it is nothing to do with decoder or motor brushes, but rather a connection between the pickups and chassis for some reason.

If on the other hand, that gets rid of the short, then the next thing to do is to replace the red wire and remove the grey and brown wires from the brushes. If that then gives a short, the problem has to be in the decoder for some reason. If not, then there is a short circuit at the brushes despite the insulation.

Mal you will probably have done all this but have you checked round the chassis for bits of metal ,track pins dropped solder etc ?
it seems to be the only reason left!
lol::lol::cool:

Hi Guys - Geoff - followed diagnostic procedure, & guess it was the decoder, so tried another one (the Hornby).  No short now, but when I try to programme, I get 'read error'.  Could this be another faulty decoder?  Thanks for help.  Mal

Still can't get this right!  I've taken everything off including the brush tensioning spring, but I still get continuity between the two brushes.  It must be by the commutator.  Any ideas any one?

So Mal, the brushes have no external wiring contact anywhere but with a ohm-meter, you get a reading on the brush terminals with the brushes still sitting there connected to the commutator?

That would be correct but what is the reading - zero ohms or  close to that or a resistance of say 50 ohms ?

Remove those brass brushes & connect the meter across two commutator segments & see what value you get; check adjacent segments. Clean between each segment with a knife blade carefully to clean old oil, etc out. You need to prover the windings are still OK.

Yes.  I'm with Sol.  Sometimes the windings in these old locos can short out.  It's not a common problem, but we're running out of possibilities. 

Mal nine times out of ten an error message is due to a bad solder joint  in particular the earth

:thumbs:lol::lol::cool:

Hi Sol - I've checked across the commutator segments & get 0 reading on them all - does this mean motor is NFG?  Am surprised because although it's old it's hardly  been out of the box & was probably run for 10 mins on DC!

Mal, if the meter ( presumably digital) shows  0 ( zero)  or if it is the older analogue type meter & the needle goes all the way across to the right, 99.9% sure that the motor is shorted - stuffed, had it, , etc . Whether replacement motors are still available, our UK based mates might have the answer.

Thanks Sol. I suppose the good news is that my 2 decoders may be OK - they each cost more than the loco did! Maybe I should look for a Bachmann pannier chassis & do a conversion.  Cheers. Mal