Hoover Ranger Senior, model, U4002, serial no, U400240800256
Hi Paul.
Will do the honours with the date thing:
U4002 = model number
4 = year! always refers to last digit of the year/you have to know the decade. Your machine is 1974.
08 = month. Your machine is August.
00256 = individual machine identity
This dating pattern was applied to most, if not all Hoover machines, until the mid 1990s and was a lot simpler that hotpoints, not requiring a date code sheet.
Paul