Ok. So I have a little bit of diagnosing to do this weekend. I actually believe it’s the head gasket because from what I’ve been reading, these engines are notorious for blowing head gaskets. I will post my findings for sure. I appreciate all the help.
No to both. I had been running the mower since spring after it's initial tune up. I haven't had the problem until now and I haven't added any oil to the engine since this spring.
Interesting ideas that I will try. One question: When doing the pressure test with my hand, should I feel a vacuum trying to suck air or should it be no suction at all?
Ok. I think I've isolated the area where the leak is coming from. It's either coming from the brass looking circle on the fuel pump or the little slot holes that go all around the pump. It's a brand new fuel pump but could it be bad too?