Mower is a Craftsman Platinum EZ walk push mower with electric push button start(as well as pull start). Briggs&Stratton engine/7.25/190cc/model 917.370930. It was purchased in 2012 brand new, used about 3 times then given to me in 2015. I did not even attempt to use it until 2016 summer. Used one time that summer. Has been stored inside until I took it out last week.
Charged battery for push button start, changed oil, spark plug, air filter etc...I couldn't get it to push button start, but pull starts fine. Started mowing, using self propel. Did great, then started noticing after mowing for about 25 or 35mins, when I would engage self propel, it would lose power. Would still run, but obviously not at full strength. So I kept mowing without self propel... did fine. Then about 25 more mins into it, I tried self propel again and it ran with very little power then sort of faded out. No sputtering or theatrics... just literally, slowly died. Why is it doing that? As long as I don't use self propel 30mins into my mowing, it runs like a gem till it's outta gas.