Yup the primer makes it easier but never had any problems with starting up a cold engine without a choke. Problem with that primer bulb is once it's cracked, you're dead in the water unless you have an extra in the tool box. I fired up my Gravely yesterday after replacing the 15 year old fuel filter (:D). The choke on that 1984 garden tractor fell off the shaft over 20 years ago and if it's not really cold, I can get it going by hitting the starter with the throttle part way open for a few seconds then closing the throttle and it'll fire off. In warm weather it usually will idle but when it's cold like it was yesterday (around 45*) I'll have to do that a couple of times or use a shot of brake wash. It surprised me it started so easily yesterday since I haven't run it in about a month.