Guess the speedometer year ?

[landroverbrit]

can anyone narrow this speedometer year down ?

[jimrr]

I've seen them, a couple of times! I can only think it's series 2?

[roverp480]

Its the same number as on my replacement speedometer as fitted to my 1955 Land Rover . The Rover Speedometer number (239564) is listed as being SN3391/01 in the Series 2 parts catalogue and was used from 1954 up to the Series 2A Suffix C chassis numbers. Suffix D was when they changed to negative earth wiring, about 1967. So to answer your question , it could be anywhere between 1954 and 1967 . I have put a call into a friend who rebuilds speedometers, to ask if there is a date code elsewhere, he advised there isn't anything that he is aware

[vlad_d]

copy of post...deleted.

[vlad_d]

Hello @LandRoverBrit!

I just went down the rabbit hole with Speedometers recently, as I went looking for a new one for my Series 3. Here's some info that might help. At least, which years it's NOT!

* The Series 3 Speedometer have 3 holes at the bottom for colored jewel lights for - I can't remember exactly - oil pressure, cold start, high beams. So, this isn't a S3 model, which you probably knew already. That eliminates 1971-1984ish?!

* Fun fact, that number at the bottom right (at least on the S3 ones) means how many turns of the shaft per mile per hour registered. Match that to gearbox output and the size of the wheels and you can figure out some stuff about the car. For instance mine is "1376" and that means it was for a Rover with 16" wheels(I have been told. I forget the exact math). "1536" is for 15" rims, I have been told.

What's "1504" then? I bet the rim size is 15". I see alot of 2 & 2a owners on this forum that talk about having 15 inch rims(comes up alot)...so I'm going to make a wild assumption that 2 & 2a came with 15" rims, mostly. Correct me if I'm wrong, guys. So, that would lead to the gear ratio difference being a good clue:
s3 gear ratio x 15 x 1536 = s3 gear ratio x 16 x 1376 = unknown x 15 x 1504
solve for the unknown (after putting on s3 gear ratio at the gearbox speedo cable start, which I don't have in front of me). Once you have the ratio, you can look up which years between 1948-71 had that? Might narrow it further?

Here's another forum link with more info:
https://www.lrsoc.com/forum/index.php?topic=28079.0

[roverp480]

1504 is the number of revs per mile the speedometer cable needs to turn and equals the rolling radius of a 6.50 x 16 cross ply tire originally fitted to Land Rovers . It is reasonably accurate for 6.00 x16 up to 7.00x16 . When the series II was introduced a different one was introduced for the 109" with 7.50 x 16 tire needing 1408 revs per mile . Series III had a slight change to 1536 for 6.00 x 16 . See General information in the attached Smiths Parts list , which does have some inaccuracies such as referring to a Series IIB 88". I am not sure which speedometer was used for the 15 inch wheels used on some US spec. vehicles
13662

[vlad_d]

@Roverp480
You've solved it! Right at the top of your pic from the catalog!
May 1965-March 1967
SN3391/01 1504(rpm)

You're not going to get any more specific than that! Well done!

[landroverbrit]

Thanks for all your input guys. I didn't even know that book existed. Good detective work everybody. Thanks for taking the time. Cheers. -Land Rover Brit