XK120 Manette questions

Happy Christmas everyone.

I have removed the manette from my 120 and there are some pieces missing so I am struggling with the finer details of construction although I understand well enough how the indicators should work and self cancel.

I have been looking at a previous thread:

I have a some specific questions. Looking at this picture which Rob Reilly uploaded…

1/ There is a brass washer at the back of the Bakelight housing what is the purpose of this please?
2/ There is another brass washer between the self cancelling ring and the back plate in the top RH corner, I suspect this one is a bush between the stationary part and the rotating self cancelling ring?
3/ What holds the self cancelling ring on? I can see that it rotates with the large disc at the back thanks to the fingers protruding from this ring, but what stops it moving backwards and forwards slightly?
4/ The grub screws in the steering wheel seem to hold the large disc (with protruding finger) so that it rotates with the wheel. What prevents the centre part from rotating?

Any help would be much appreciated!

In response to number 4, the tube that is about 8” long attached to the manette, has small bumps along the shaft. These slide into a slot on the stator tube which is inside the steering column and fixed by a clamp at the front of the steering box. As the wiring is fed back down the stator tube (hopefully while someone pulls them through via the string previously recommended), you will feel the bumps engage the slots. Slide the manette all the way till it stops. Silicone lubricant on the tube helps. As the in and out is adjusted, the steering wheel moves in and out in this slot. Adjustment of the orientation of the horn/turn signal can be done by loosening the clamp on the stator tube.

Many thanks Lewis, great explanation that makes perfect sense. That’s one of the 4 knocked off the list then.

Anyone for the others?

3 screws hold the Bakelite to the base plate

brass bearing washer

felt washer on back of brass washer

brass front “washer” with electrical tab connecting to front stud

long brass screw holds Bakelite halves together


as do two other studs.

nubs on outer manette shaft


Notice the tape, this is a wear point on the wires as the wheel is moved in and out and the wires are rubbed on the sharp edge of the stator tube, an engineering design defect. Mine would blow fuses when I signaled a left turn. I wrapped tape as a temporary fix, and later substituted with shrink tubing.

slot on inner stator shaft
PICT0008

brass contact disc, the plastic push clips to this
Picture073

contact tabs

3 Likes

Brilliant thanks Rob that’s really useful. How many wires do you have please, is it 4? If so I’m guessing the brass front washer with the electrical tab provides the earth for the horn? I am missing this but have 5 wires so I’m thinking someone has run an earth back down the stator tube.

The other thing, I still can’t see how the self cancelling ring which fits around the Bakelite housing doesn’t move backwards and forwards. What holds this against the back plate (where the screws go through to the Bakelite)?

I have bits missing and have haven’t seen a complete one assembled!

Thanks again and Happy New Year.

In Robs 6th picture it shows the cancelling ring and circular spring

This area is also where the L/R indicator brass contacts touch and allow current to flow

I have some Mannettes, and two of them have the fault that one of the indicator circuits has no continuity

I dismantled one, repaired wiring and re-assembled it, but the fault was still present

It appears one of the the inner brass contacts is the likely culprit, so I would have to dismantle it again to make it operational, not an especially pleasant thought

So be aware to maybe polish the contacts

Thanks Tony. The bit I meant was this ring here which fits around the outside of the Bakelite switch module. I don’t quite see what stops this moving forwards in the direction of the bottom arrow…

Manette

There is an internal flange or step in the self canceling ring, which prevents it moving toward the Bakelite.


There is a step on the Bakelite that also stops the ring moving axially.

I have four wires, 1 purple and 3 shades of green.



Thus the color scheme does not match the wiring diagram, so light green is right turn and connects to the green/yellow wire, dark green is left turn and connects to the green/blue wire, medium green is common and connects to the green wire, and purple is horn and connects to the brown/black wire.

Ah I see, thanks Rob.

The plot thickens however…

…here is a picture of my Bakelite housing without the step on the housing!

This is obviously meant to be reset in the same sort of way because it has the two cancelling pawls protruding from the Bakelite. I do note it has a step on the front of the housing though so perhaps the cancelling ring (which I’m missing) was different on this one.

Dear all,

Yesterday a brand new 1954 manette reached me from Oregon (thanks Rob).

I will post some pictures, as I needed to dismantle it and adapt it to negative earth for the claxon.

Now everything works beautifully.

Best,

Ll.

Not being an expert these seems to me 54 production date. It was positive earthed, meaning that the claxon was wired to the ground directly, simple modification to adapt.

Four cables, screwed not soldered.

Multiplate spring contact, soldered to the screws.

Plastic and chrome were like new.

By the way, my unit does not have the self-cancellation disk.

There should be no need to change anything on the manette for negative ground. Horns and horn relay don’t care what ground it is.

Correction: the cable from the relay was wired to the wrong leg, hence “always grounded”: I needed to connect to the other leg.