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Speedo drive gear

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SJ has run out of speedo driven gears A079F6054F. Anybody knows a potential source for that part?

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If your unit is inop (no drive), you MAY be able to repair it.  Sometimes the  right angle gears disengage because the end caps come loose.  (Of course, you cannot remove the drive unit to inspect the circled gear without removing the rear trans cover.)

 

If you DO need a gear, I agree that Harry's is the place to inquire.   http://ds-vitesse.com/en/

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Thanks Steve and Atwell. My unit operates but the speedo needle has a bit of a wobble. I cleaned up the speedo itself (which happened to be fine) and swopped in a new cable too. The wobble is less now but still annoying. I Guess it’s an accumulation of play in the whole system. The gears at the back is the most obvious wear part. I’ll check with Harry. Yes, I’m aware that the backplate has to come off. Next tranny oil change then...

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Have you lubricated the new cable with a graphite lubricant?  (NOT Lubriplate as so many places recommend!)

 

Did you chamfer (round off, a little) the square ends of the new cable?

 

 

(OK, I just dated myself with my knowledge / experience of mechanical speedometer drives.) :sofa:

 

Hey if it really bothers you, you could install a SMITHS replica GPS speedo!

https://www.ebay.com/itm/85mm-Smiths-Replica-GPS-Speedometer-KPH-Car-truck-Bus-Motorcycle-Hotrod-Proj-/172822321667

 

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I have a small GPS HUD display as a backup and I’d like to retain the original cockpit look. Didn’t use a graphite lubricant, it was a regular spray on lubricant. Thanks, might be worth looking at again. 

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To conclude this thread, my speedo wobble was caused by a similar issue to Andy’s 

While lubricating my angle drive I noticed that it moved up by 2mm thus it had quite a bit of play.  That play was enough to create a gap tolerance between the angle drive taper shaft flat and the speedo gear in the box when the drive is at the upper end of play. A simple temporary rubber band solution to hold the drive in for a test drive produced a steady speedo needle. Nice. Next is to devise a more permanent solution to hold the bugger down at all times while still allowing it to rotate a bit as it’s intended. 

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Well, I was probably somewhat wrong with my previous post. The angle drive, nylon cartridge and drive gear should come out as one connected unit upon removal. The wobble originates from the complete unit, incl lower small gear, not being fully engaged with the larger drive gear on the gearbox main shaft. Now I have a couple of questions: what actually holds the small drive gear onto the angle drive shaft? It’s a flat tapered shaft on the angle drive and the corresponding slot on the small gear. What stops the small gear from dropping into the gearbox? Will the whole assy come out if the long bolt is removed or is there a risk that the small drive gear remains in the box? Last but not least, where does the small O-ring sit? Atop the angle drive brass shaft?

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There is a "thing" which stops the gear falling into the box. Cant remember any more details than that :)

The whole drive should come out if you remove the long bolt or in my case even if you dont remove it (never got to the bottom of that!).

I think a lot of problems in this area are caused by the box running backwards from its original design so maybe tends to push the gear out of engagement. Thats the sole function of the right-angle drive, to reverse the cable rotation back to normal.

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Thanks Andy. I’ll pull the drive and replace the nylon cartridge eventually. For now, I’m happy with a steady speedo needle, thanks to a temporary strap holding the drive in fully. 

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Just remembered on mine the issue is if the long bolt is not removed, the inner brass section still comes out. The nylon outer is held in but not the inner brass section.

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