"when looking up your engine o
"when looking up your engine on that site above there is no serial number 64xxxxxx in the right listing. Be sure to look farther down the page at the 1150, and not 115. The 64xxxxx is a much later version, as seen in this list
115 5168574 - 5600966 1979 6 cyl inline
115 5600967 - 6006833 1980/1981 6 cyl i/l (80/81 = samma modellår)
115 6006834 - 6262960 1982 6 cyl inline
115 6262961 - 6440182 1983 6 cyl inline
115 6440183 - 6630170 1984 6 cyl inline
115 6630171 - A907776 1985 6 cyl inline
115 A907777 - B110053 1986 6 cyl inline
115 B110054 - B239241 1987 6 cyl inline
115 B239242 - C099999 1988 6 cyl
or this
1150 (115,0) 2836019 - 3023085 1970 6 cyl inline
1150 (115,0) 3023086 - 3270479 1971 6 cyl inline
1150 (115,0) 3270480 - 3525440 1972 6 cyl inline
1150 (115,0) 3525441 - 3761034 1973 6 cyl inline
1150 (115,0) 3761035 - 4112634 1974 6 cyl inline
1150 (115,0) 4112635 - 4310784 1975 6 cyl inline
1150 (115,0) 4310785 - 4567951 1976 6 cyl inline
1150 (115,0) 4567952 - 4855152 1977 6 cyl inline
1150 (115,0) 4855153 - 1978 6 cyl inline
we need to pin down the year a bit to help
ps, I was boating yesterday so I couldn't help"