Well…I purchased a manual for the motor off Ebay. The manual states it covers ALL Sears Elgin, McCullogh & West Bend from 1960 to 1969, 3.5 t0 75hp. All I can find in it for the 1961 40 is the gear case break down. My motor has a Tillotson carb on it. The manual only covers Walbro and Marvel-Schebler carbs. It does not even mention the Tillotson. Can anyone direct me to the proper manual for this motor?