I had a Briggs and Stratton that had almost no compression. Had to mix oil with the gas just to restore some lost compression so I could mow. This was a push mower by the way. I finally decided to finish it off by draining all the oil out and running it at full throttle, without the governor. It lasted for 45 minutes before seizing. Then I broke it loose and got it to run again. I was hoping something inside would blow, but it didn't. Then I took it apart and the piston and cylinder were all scuffed to shit.