Speedo rebuild

The odometer works just fine, and is accurate, so it's not a cable issue.

From cold, the speedo is broadly accurate (although I've not checked it
against GPS), and the needle smooth. But, after about 10 miles or so, it
becomes ever more pessimistic, until it refuses to acknowledge anything
above 30. The other day, it decided 30 was where it REALLY wanted to be,
and just stuck there, even when the speed dropped. A day later, I got
back in the car - and the speedo still read 20, until I moved the car,
at which point it decided that we really were stationary.

The odometer says 42k miles, and is accurate and original, so I don't
want to just lob a replacement in.

Anybody got any experience of recommendations in getting 'em rebuilt?

View attachment speedo.pdf
Some info here

Blackburn said:

View attachment 68152
Some info here

Click to expand...

Thanks, with a large helping of "eeek!"...

Perfect weather for removing the speedo and bringing it indoors in the warmth for a good poke about!
Second option is ebay. If you plan to put bigger LWB rims on it you might just want to get a corresponding replacement so it doesn't under read.

Just read about this in one of my books (The series 1,2 and 3 restoration book by lyndsay porter). The bit in the book reads like this:

"speedo reads normally when cold but reads slower after a few miles, this indicates that the output flange nut on the transfer box is loose, allowing the handbrake hub to move, trapping the speedo drive gear and allowing the speedo drive gear scroll to slip. This is cured by tightening the nut up."

samc88 said:

Just read about this in one of my books (The series 1,2 and 3 restoration book by lyndsay porter). The bit in the book reads like this:

"speedo reads normally when cold but reads slower after a few miles, this indicates that the output flange nut on the transfer box is loose, allowing the handbrake hub to move, trapping the speedo drive gear and allowing the speedo drive gear scroll to slip. This is cured by tightening the nut up."

Click to expand...

It's an interesting theory - but wouldn't that cause the odometer to lie, too? And it wouldn't account for the speedo staying at 30 when the speed dropped, and 20 after being parked for a day.

A mate on one of the classic car mags has sent me some more stuff that expands on the PDF above, and makes it a bit clearer for muppet-chops here. So I think I'm almost brave enough to dive in there and see what's what...

Speedy cables will service it and calibrate it for you - not sure how much they will charge for parts but they quoted me £60 to recalibrate one some time ago...which is sat on top of the fridge waiting for me to send package and send...