Correcting Speedo
As per the previous postings: refer to the parts book.
Obviously Rover kept the tyre size as the defining factor which for us is 7.50 x 16. Why make it any more complex? For the average person, the SNT only becomes a means of confirming that no one has buggered with the speedo.
What some one could do within this group would be to compile a list of the correct speedos:
Rover part number
Markings on face
Jaeger/Smiths code number
and if you really want, the rpm.
Just having looked at both of my speedos for the SNT;
Original
6209/25
Replacement
6209/35 (no markings on face, sticker on side)
If all is correct, have you checked your gearbox or diff serial numbers to see if they have been swapped?
Obviously Rover kept the tyre size as the defining factor which for us is 7.50 x 16. Why make it any more complex? For the average person, the SNT only becomes a means of confirming that no one has buggered with the speedo.
What some one could do within this group would be to compile a list of the correct speedos:
Rover part number
Markings on face
Jaeger/Smiths code number
and if you really want, the rpm.
Just having looked at both of my speedos for the SNT;
Original
6209/25
Replacement
6209/35 (no markings on face, sticker on side)
If all is correct, have you checked your gearbox or diff serial numbers to see if they have been swapped?
I have a Stage I speedo drive pinion I've just had a look at and it has 20 teeth on it. The worm gear, which is a bit harder to describe, has 5 teeth across at an angle of about 10 degrees. Hopefully that will help someone trying to identify a part.
So, to clarify:
A Stage I speedo head is the same as any other SIII 109" speedo for 7.50/16 tyres.
It's not the same as one for an 88" with 6.00/16 tyres, or the 109" 1-ton with 9.00/16 tyres.
Now, I think I've got that right?
So, to clarify:
A Stage I speedo head is the same as any other SIII 109" speedo for 7.50/16 tyres.
It's not the same as one for an 88" with 6.00/16 tyres, or the 109" 1-ton with 9.00/16 tyres.
Now, I think I've got that right?
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map1275, thanks, I think I understand at long last. Is the SNT you refer to, the four digit TPM number I was using? Might it be possible Land Rover changed this over the years as they adopted different tyre brands, with very slight differences in rolling circumference?
Anyway, decided it was far too cold to be messing around under a Land Rover yesterday, and figured I might as well wait til I have a replacement speedo drive, so had the Better Half drive at various speeds whilst I followed. I realise not going to be 100% accurate but was made a little easier as she has cruise control and a digital speedo.
Here's the results (her speedo/my speedo): 30/25, 40/34, 50/43, 60/52, 70/60. At the end of journey her trip showed 9.6 miles: mine 7.9 miles. Not quite as much of a difference as I'd hoped, but at least it wasn't just my imagination.
Tel, using the above figures, imagine how chuffed I was to calculate I got just over 18mpg from my first tank, mainly motorway, without an overdrive. Unfortunately you're right, the second tank worked out at 13mpg!
Regards,
John
Anyway, decided it was far too cold to be messing around under a Land Rover yesterday, and figured I might as well wait til I have a replacement speedo drive, so had the Better Half drive at various speeds whilst I followed. I realise not going to be 100% accurate but was made a little easier as she has cruise control and a digital speedo.
Here's the results (her speedo/my speedo): 30/25, 40/34, 50/43, 60/52, 70/60. At the end of journey her trip showed 9.6 miles: mine 7.9 miles. Not quite as much of a difference as I'd hoped, but at least it wasn't just my imagination.
Tel, using the above figures, imagine how chuffed I was to calculate I got just over 18mpg from my first tank, mainly motorway, without an overdrive. Unfortunately you're right, the second tank worked out at 13mpg!
Regards,
John
1982 Stage 1
1982 88"...dormant in back garden!
1982 88"...dormant in back garden!
There's no need to over think and make things more complex than they need to be.
What is the sequence written in small characters at the very bottom edge of your speedo? Or if its a later replacement, this may be on a sticker on the side of the speedo's body.
This is what's used to ID the speedo, not anything else.
What is the sequence written in small characters at the very bottom edge of your speedo? Or if its a later replacement, this may be on a sticker on the side of the speedo's body.
This is what's used to ID the speedo, not anything else.
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- Joined: Tue Dec 09, 2008 8:20 pm
- Location: East Sussex
map1275, believe it or not I crave simplicity! Got the SNT number...6209 42. Can see part numbers are same for Stage 1's...query in my last post regarding different TPM numbers was just out of curiosity; had realized (at long last!) speedo head is not the issue with my vehicle. Thanks for your help again.
Davo, thanks for clarifying that, by the way.
Regards,
John
Davo, thanks for clarifying that, by the way.
Regards,
John
1982 Stage 1
1982 88"...dormant in back garden!
1982 88"...dormant in back garden!
JohnJohn Roach wrote:map1275, believe it or not I crave simplicity! Got the SNT number...6209 42. Can see part numbers are same for Stage 1's...query in my last post regarding different TPM numbers was just out of curiosity; had realized (at long last!) speedo head is not the issue with my vehicle. Thanks for your help again.
Davo, thanks for clarifying that, by the way.
Regards,
John
I have a Stage 1 with the same issue! have you resolved yours yet?
Thanks
Aidan
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- Posts: 59
- Joined: Tue Dec 09, 2008 8:20 pm
- Location: East Sussex
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- Posts: 59
- Joined: Tue Dec 09, 2008 8:20 pm
- Location: East Sussex
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- Posts: 59
- Joined: Tue Dec 09, 2008 8:20 pm
- Location: East Sussex