Loading....
Please wait
J D O Instrument Engrs
Classic Car Instrument Repairs ( Est 1963 )
Tele: (UK) 01535 672125 Mobile / SMS: 07831 886545
Fixed price repairs for most British & European Classic Instruments
48 hr service available... Why pay more & wait longer ! no vat
48 hr service available... Why pay more & wait longer ! no vat
‘Good luck with your project’... Enjoy your classic motoring...
Fixed price repairs are based on the assumption that unit/s received
are ‘original & complete’... a surcharge may be applied to cover
missing parts etc... If in doubt send in the unit for inspection
Fixed price repairs are based on the assumption that unit/s received
are ‘original & complete’... a surcharge may be applied to cover
missing parts etc... If in doubt send in the unit for inspection
If you found this web site via a ‘search engine’ please
check that you are looking @ the latest version... click here
Tip! Press F11 for a full page view @ 1024 x 768 screen resolution
press F11 again to revert to normal view contact the webmaster
check that you are looking @ the latest version... click here
Tip! Press F11 for a full page view @ 1024 x 768 screen resolution
press F11 again to revert to normal view contact the webmaster
Jaguar XK 120 ( 1948 / 54 )
708.1M
Payment options
Information required to Check / Re- Calibrate a Speedo
print off a copy & enclose with your order... see Site Map for tips on printing only the information required ( saves ink ! )
*Jack up just 1 Driven wheel Measure the Circumference of the fitted tyre in inches = ________ cms = ________
Remove the Speedo...make up a cardboard pointer or similar & fix it to the end of the exposed inner speedo cable ...
Put a chalk mark etc on the edge of the tyre & the ground ...
Now turn the ‘Jacked up’ road wheel 20 turns forward ( out of gear )
& count the number of turns the speedo cable makes = ___________ to the nearest 1/8 ( eighth ) of a turn
* The above assumes a Normal diff unit ... if the car is fitted with a Limited slip diff (LSD)...
Jack up Both driven wheels & turn one wheel 10 turns forward ( out of gear )
take up the slack first ( approx ½ turn ) this gives the same result
Please confirm tyre size ___________________ type of tyre Radial / Cross-ply ( delete one )
However if your car is on the road & running ask a friend etc to pace you in another car with a speedo known to be
ok... i.e. set the Trip on both cars to zero ... Travel approximately 10 miles / 16 Km & advise both readings
e.g. True distance = _________ Your cars indicated distance = _________ to the nearest 1/10 ( tenth ) of a mile / Km
print off a copy & enclose with your order... see Site Map for tips on printing only the information required ( saves ink ! )
*Jack up just 1 Driven wheel Measure the Circumference of the fitted tyre in inches = ________ cms = ________
Remove the Speedo...make up a cardboard pointer or similar & fix it to the end of the exposed inner speedo cable ...
Put a chalk mark etc on the edge of the tyre & the ground ...
Now turn the ‘Jacked up’ road wheel 20 turns forward ( out of gear )
& count the number of turns the speedo cable makes = ___________ to the nearest 1/8 ( eighth ) of a turn
* The above assumes a Normal diff unit ... if the car is fitted with a Limited slip diff (LSD)...
Jack up Both driven wheels & turn one wheel 10 turns forward ( out of gear )
take up the slack first ( approx ½ turn ) this gives the same result
Please confirm tyre size ___________________ type of tyre Radial / Cross-
However if your car is on the road & running ask a friend etc to pace you in another car with a speedo known to be
ok... i.e. set the Trip on both cars to zero ... Travel approximately 10 miles / 16 Km & advise both readings
e.g. True distance = _________ Your cars indicated distance = _________ to the nearest 1/10 ( tenth ) of a mile / Km
Continued on next page
Calculation page
Re-Calibration surcharge