I think i have worked out some consistency with the Series 70 Numbers, Judging by the ones i have collected sop far.
For some (earlier ones) they show 2 digits for the year, later they only showed one.
Here's the key:
First Digit = 0-1, and 6th digit = 0: Last 2 Digits of year are positions 4&5
First Digit = 2-9, and 5th digit = 0: Last 2 Digits of year are positions 3&4
First Digit = 0-1, and 6th digit = 1-9: Last Digit of year is in position 4
First Digit = 2-9, and 5th digit = 1-9: Last Digit of year is in position 3
Examples
11371098767 = 1971 (Key 1)
02373066723 = 1973 (Key 1)
1629033645 = 1979 (Key 3)
5480667000897 = 1978 (Key 4)
034770667399 = 1977 (Key 1)
034706673999 = 1977 (Key 3)
034700673999 = 1970 (Key 1)
237609987767 = 1976 (Key 2)
1760077886677 = 1980 (Key 3)*
1970-1976 were Double Digit, 1978-1980 Were single (limited run in early 1980) so a year code of a single zero would be 1980. 1977 i have not found yet, so 1977 is given in 2 examples.
The numbers at the end variate substantiated, so the length of the code is inconsistent (imitated in examples)
This is only based on my own observations, so may not be correct, as i gather more numbers, i will make any updates necessary.
UPDATE: some issues found regarding 1979 & 1980, as known engines from these years seem to all have both a 9 and a 0 in the year vicinity, still trying to work out a pattern.1979 fits as above, 1980 may not have a second 0 after the indicating 0.
FURTHER: Dug out a 1963 Victa Engine (Known, provided with original documentation) and found the 3rd and 4th digits were 63, so above dating system seems to go back further than 1970, This is also seen in Chris's 1969 Corvette!
Last edited by Mr Davis; 26/07/11 10:47 AM.
