the 'next page' of the 1938 manual states 50 wt must be used when the heavy duty air cleaner is used in place of the standard one .... can anyone identify the difference between the standard and the heavy duty air cleaners for 1938?
OTOH, the 50's manuals specifically call for 50 wt in the 'standard' air cleaner, but in 1955 they call for 20 wt in 'freezing weather' .... is it really going to make much difference? I've always used the same 10-30 in the air cleaner and the 283 in my 58, summer or winter, maybe I'm getting a little 'top end' oiling?
Bill
