There was a request for help a few days ago in the DCC forum
about fitting to a J94. I helped answer the query, but by
coincidence, I was askd to fit one by a customer yesterday.
So here it is (Hopefully it will be of help!)
Undo the two screws under the cab (Circled)
And the screw in the chimney
Carefully lift off the body (the cab is clipped in). Undo the
two screws holding the weight to the chassis (Circled)
The weight has a protrusion on the underside that will have to
be removed if a decoder is to be fitted.
Here is the weight after milling - the semi-circle of metal has
now been ground off.
Turning to the chassis, remove the screws from the motor keeper
plate (Circled red) and unsolder the black and white wires from
the motor, threading them through the keeper plate. put the
plate to one side.
There are four wires in the Hornby model. Unsolder the black
wires from the motor.
Pair up and bind the pick up wires. trim the redundant wires on
the decoder to a 1" length and the other wires to a 2" length.
Connect the Black wire to the black and white wires on the
chassis.
Connect the red wire to the black wires on the chassis (or the
loco will run backwards)
connect the grey wire to the lower motor terminal
then thread the orange wire through the hole in the motor keeper
plate, and replace the plate.
solder the orange wire to the upper terminal on the motor.
The hole in the front of the chassis is an absolutely perfect
size for a lenz silver decoder. Tuck the wiring underneath and
clip the decoder into the space.
Now test the loco and ensure everything is working correctly.
Pop the weight back on and replace the screws. You can see the
decoder between the chassis and weight.
Put the body back on - being careful not to damage the clips on
the cab.
