I have just bought a second hand Suffolk Colt mower which looks as though it
may be around 40+ years old. I have been looking for any instructions on the
web but I think the model is too old. The question I have is about what
petrol grades I can use. I assume that it was designed for leaded petrol
given its age but I don't know whether it is possible to use unleaded with
it or if this would damage it. I would be grateful if anyone were able to
point me in the direction of some information on this model.

Many thanks in advance

Andrew