anything with an oil cap was probably made to oil usually with something like 20w non detergent. Something like 3 in 1 oil will work. I wouldn't put in more than 2 or 3 drops. Never put oil in while it is running. Chek-Chart made lubrication charts for the oil companies in the 50's and 60's and maybe later when gas stations still serviced cars. Their recommendation was "lubricate sparingly every 5000 miles with motor oil"