Firstly DO NOT lose that manual, it is very valuable these days...
Looks like a very tidy victa 18 there! It has the wrong air filter housing, it may be having trouble running also without the snorkel tube, these were cut to adjust the tuning in the past.
Chances are the crankshaft seals are leaking, afterall they are probably years and years old, they are pretty cheap and good insurance on your motor.
