Lotus Elan

Speedo not accurate

PostPost by: l10tus » Sun Jun 14, 2015 1:10 pm

Upon driving the car to its post refurb. MOT, I notice the speedo is erratic.

It's a new cable and I've checked its free running, also that the square drive and take-off from the gearbox is ok.

It works, - but reads slow, then fast, then seems to seize/ bind up, at about 30 - 50 MPH.

However, Once the car is parked, it falls back to zero.

I checked the original ( or what I believe to be the original) - route for the speedo
Cable, out of the bulkhead via a rubber grommet, but it then has to take a couple of really tight bends to either go under, around the front, or clear the back of, the cold air box?

Q: what is the correct route ?,
Q: has this always been a problem issue on the Elan?
Q: Is there any other remedy ?
Q: is the route of the cable binding the inner cable causing the problems?

Your thought would be appreciated.
Regards,
Phil.
Last edited by l10tus on Sun Jun 14, 2015 5:52 pm, edited 1 time in total.
Philip.

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PostPost by: billwill » Sun Jun 14, 2015 2:13 pm

Might be dust or sticky pivots in the actual instrument.

But they are very tricky and delicate, so don't try service it yourself unless you are already such an expert.

In my past oscilating speedo needle was always due to a worn cable; maybe your new cable is a not-to--good chinese replica?


~~~
Sorry I don't recall the route of the cable off the top of my head.
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PostPost by: lotusfan » Sun Jun 14, 2015 3:24 pm

Phil

The route for my speedo cable is out of the bulkhead then a slight right turn towards the side of the car and then a long flowing curve under the cold air box across the top of the foot well down towards the fuel pump and finally heads backwards down the transmission tunnel.

Hope that helps.
Mike
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PostPost by: l10tus » Sun Jun 14, 2015 5:56 pm

Billwill & Lotusfan,

Thanks for that info.

The initial bend after coming out of the bulkhead is quite severe, so I maybe have gone the wrong route?

I'll check the route and try to re-adjust.

Regards,

Phil.
Philip.

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PostPost by: l10tus » Tue Jun 16, 2015 4:21 pm

Checked the route and eased it slightly, following the advised route, but still seems an unnecessarily very tight route?

Why was the hole not moved over towards the off side a little more, to elevate the need for such a tight bend - any ideas?

Are there other items in the way?

Regards,

Phil.
Philip.

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Sometimes my Lotus makes me cry.
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