Comparing the original carb idle jet i.d. (.060) and the replacement carb (.025) I've confirmed what several of you have posted. I did drill out the idle jet of the new carb to .060 with a pin vice and drill and the motor ran better but an issue with the needle and seat prevented calling this cycle a success. I bowed to the time crunch and bought an o.e.m. Briggs carb which proved to be the answer. I wanted to take the new Briggs carb apart and measure the idle jet but.....nope. Mower runs very well throughout the throttle range and pulls the blade engaged load very well also. Vast improvement over what it was when I got it. Of course the carb wasn't the only thing this mower needed: Oil/filter change, air filter, fuel filter, new blades, all new deck pulleys, belt and spindles, new drive belt and idlers. Hope the owner/customer takes better care of it this time around. It is stored outside under a cover, not good. Thanks for all the advice!!