Craftsman ZTS 6000 with model 331677 Platinum engine started smoking intermittently and is leaking oil. It looks like the leak is coming from the fuel pump.?? The air filter was dirty and was replaced with a new one with no change. Compression wet/dry both 120 psi. Oil was filled to correct level and it used 1/4" on dipstick in about 20 minutes. It starts and runs good but engine will stutter every few seconds and a puff of smoke comes out of the exhaust. The mower is 6 years old and has only been used on a small yard. Photos attached.