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[jbcollier]

Yes.  The gear runs in a plastic housing.  The plastic housing is held in by a set screw from the side.  Back off the set screw and you'll be able to pull out the plastic housing.  Sometimes these are glued in with silicone sealer and removal will be awkward.  Now you can examine the drive gear.  Hopefully it is damaged but not the large internal gear.

[Gary t]

Thanks John a weekend project.

[Dilkris]

Anything you see in these pictures which is made from Nylon are your speedo drive components - this is what you are focusing on. Good luck. 

[dakazman]

   This vendor was just posted on groups, posting link here seems appropriate.

    http://www.speedograph-richfield.com/
 
Dakazman

[Gary t]

Thanks for the great photos.  I plan to attempt to extract the driven gear and plastic support this weekend. If successful il post what I find.

[Dilkris]

   This vendor was just posted on groups, posting link here seems appropriate.

    http://www.speedograph-richfield.com/
 
Dakazman

  TBH - ashamed to admit I have never heard of them - but most certainly a very valuable link.   

[Gary t]

Small extraction.
The driving gear looks ok, the driven gear not so much.

[jbcollier]

Frankly, that is excellent news.  You now know what the problem is and parts are readily available.

[Gary t]

I jacked the back up to get the oil away from the drive gear, cleaned the swarf off of the driven gear put it together. The output turns with a wheel until the bad part reaches the driving gear then it stops. If I gently turn it it picks up a tooth and goes 1 revolution and stops.

[Dilkris]

Frankly, that is excellent news.  You now know what the problem is and parts are readily available.

Knowing what the problem is - is one thing - now delve into what caused it. Your photo seems to show not a worn driven gear but a gear that has failed in one section - suggesting that something further down the drive train seized, or approached seizure.

[Gary t]

Dilkris I know. The cable turned quite hard and 90° drive was also sticky. Also I have no idea when it went bad. I think I would  advise  new starts to pull the 90° drive out of the transmission until they get around to speedo stuff.

[Dilkris]

I am not at the speedo cable stage as yet with my car - (body and chassis are still some distance apart  ) - but reading past comments on this forum regarding the cable I gather it runs quite a torturous route and for some members has failed often - there is mention of using a 90 degree drive into the back of the speedo instrument to assist with the route, but I cannot comment further on this - (from memory it's origin is Triumph - but I could be wrong  )
I'm sure members that already have the tee-shirt for this issue will advise further and with more clarity.
In any event - I think you were lucky - your repair is quick and moreover accessible, which for a Europa is unusual.    

[MRN I J]

just found this on the web https://lotuselan.net/forums/viewtopic.php?f=31&t=40563&start=
will do this to my car then the speedometer should be correct whatever sized rims & tyres I use, possibly fit to customers Aston's aswell as our own with which i got pinched a year or 2 back by a camera

the gps unit mentioned is available from https://www.classicautoinnovations.com/contact

[BDA]

Hopefully, this isn't a bad time to mention that if your speedo gear is NLA (there was a discussion maybe a couple of years ago that replacement speedo gears were not available for at least for some trannies - I don't remember which ones) or if you are worried about the drive system (cable, cable routing, lubrication, etc.) for any reason, you do have options. Smiths makes an electronic speedo that can be driven by a Hall effect sensor or a GPS antenna. SpeedHut sells customizable gauges, including a GPS speedo, that can be made to look very similar to the original Smiths speedo. Here is a thread about it here (http://www.lotuseuropa.org/LotusForum/index.php?topic=660.msg4256#msg4256). A picture of the actual speedo in the dash is at the end of the thread.

I should also say that I've also trod this path. My speedo gear destroyed itself when I was driving in my neighborhood leaving me with only third and fourth gear. When I got home, I opened up the tranny and found nylon shards all over the place. I had it cleaned out and put back together. Then I replaced the original speedo with a Smiths electronic unit and eventually with a GPS antenna. I don't know why the speedo gear destroyed itself. I thought I had lubricated the cable properly. I thought I had run the cable so as not to have any sharp bends. It could very easily be because of something I did or didn't do as well as I should or maybe something shifted just a little bit in the tranny so one gear ate the other or maybe age could have played a part(?). In any case, I'm happy not to have to worry about it any more.

I just thought a different perspective might be useful.

[BDA]

just found this on the web https://lotuselan.net/forums/viewtopic.php?f=31&t=40563&start=
will do this to my car then the speedometer should be correct whatever sized rims & tyres I use, possibly fit to customers Aston's aswell as our own with which i got pinched a year or 2 back by a camera

That's very nice. If I had known about that when I did mine I probably would have gone that route as I suspect that the motor unit probably doesn't cost any more, and could cost less, than the electronic speedo and your speedo matches the tach!