Speedo drive setup issue

[Norge]

Hi Guys
I'm hoping someone can tell me what might be the issue with this speedo drive setup. I've had my 1979 3CL 1000 for over a year now running around the place with no speedo so I finally got around to fixing it but it seems to be all wrong to me. the speedo drive has had a new worm pressed on but the rest is how I got it.
to me the speedo drive does not seem to sit far enough down as the washer is in no mans land and the bass part does not screw all the way down either and has a spacer on it.

 

[Legs]

Assuming it is the same set-up as on an RGS, the brass bit on mine is much longer and holds the driven worm gear in place. Plus, not sure that split collet (for a better name) is part of the assembly.
Somebody will be along shortly to agree with me or otherwise

 

[sfcpiet]

Looks like a Classic Case of Thrust Washer Ommission. Seems the gear has worn the brass insert resulting in far too much fore-aft movement of the gear. That split collar thing seems to be a bodge of some sort. Source a new brass insert and the correct thrust washers and all should be good. The gear should have about 0.5mm axial play in the housing. Omit the collar and see where you are.

piet

 

[Norge]

Thanks Piet & legs
I will look into getting some new parts.

Piet do you know of any photo's that show the correct set up and how it should look ?

 

[sfcpiet]

No need for pics.

You require a thrust washer on both sides of the gear and if you then have more than 1mm axial play, you will need a new brass insert, or otherwise shim the gear to achieve the clearance.

piet

 

[Norge]

Thanks again Piet,
just one more question in the first photo with the worm drive installed should it go all the way down so it sits on the washer as in the photo that's as far as it will go

 

[sfcpiet]

The worm gear should go all the way to the thrust washer. The washer would be completely pointless if it didn't.

piet

 

[Jo]

No need for pics.

You require a thrust washer on both sides of the gear and if you then have more than 1mm axial play, you will need a new brass insert, or otherwise shim the gear to achieve the clearance.

piet

Ha, there are pictures available. Remember when you helped me last May with a used carrier? Left side shows speedo drive of my 3c as should be with the new (used) carrier housing you found for me.

Right side shows the old carrier housing (upside down). There the previous owner had omitted the upper thrust washer which resulted that the whole worm gear axle had milled upwards into the carrier - until the gear wheel had no contact with the drive ring anymore. Appr. 6mm of material had been milled away:

Cheers,
Jo

 

[Norge]

that is what was doing my head in so if the worm is sitting in the correct position on the shaft there must be some sort of foreign object in the housing that is stopping it from going all the way down