Classic cars forum & vehicle restoration.

[Roger-hatchy]

Dose anyone know with whom, or were, I could get a speedometer calibrated.

My speedo on the DLM is about 5 to 10 MPH out

It is driven via a split pulley on the prop-shaft, fitted on the splined section of the front tube.

This drives a belt to a small gearbox bolted to the chassis with the speedo cable drive from the back of the gearbox.

I presume one could back calculate by the rear wheel radius.
Jack the car up turn the road wheel work out the ratio. but where would I go from there.

Any ideas please

[Greg]

Hi Roger,
Having just refurbished the speedo in my Ford Popular, (although different to yours), I found a rather interesting write-up on the topic, (use the link below).Although it lists Austins, further down the page there is info on calibration etc.
You may have already seen this, but hope it can be of help to you

http://homepage.ntlworld.com/johnstonrh/a30a35/speedot.htm

All the best,
Greg

[MVPeters]

Roger

The link Greg posted is a good one;
there are several others here: http://www.oldclassiccar.co.uk/forum/phpbb/phpBB2/viewtopic.php?t=8434

Since you have access to a GPS, I would use it for a few days & get a real "sense" for how much the speedo is out, & at what speeds. Don't waste time with 1/4-mile measurements! (Apologies to those who think this is a good idea!). RECORD THE RESULTS on a piece of paper & then decide what adjustment needs to be made.

But I think all you really need to do is to gently pry the needle off & move it backwards or forwards by 5-10MPH. Check the "In-Car Calibration" section in the A30 link.
Take the glass out.
Move the needle up to 30MPH or so, hold the drive spindle firmly with a thin pair of pliers, pry the needle off, move it by however much you need & push it back on.
Gently check that it gently springs back to zero.

As the A30 link points out, speedos are not that accurate; for your car & the likely uses & speeds, as long as it's within 3-5MPH at 30 I wouldn't worry about it too much!

Mike

[Richard H]

Try this chap:

http://www.jdo1.com/

I've never used him, but he rebuilt the speedometer in my last A35 for the previous owner - well, it worked alright!
_________________
Richard Hughes

[Riley Blue]

Here's another: http://www.autoinstrumentservices.com/index.php

Not had to use him but have spoken to Adrian at shows and he seems to know what's what.