The road to Hell is paved with good intentions. Old head gasket or new one, this thread, while interesting, is becoming tangential to helping Paul's Toro get his mower running smoothly. On that front, while checking the the governor by manually operating the throttle valve as I had suggested earlier, try lowering the speed of the engine. That will increase the vacuum in the intake manifold and further reduce fuel requirements. So if there is an air leak or excess fuel delivery, it should become worse. While doing this test, note the exhaust, which you can use to help differentiate between rich and lean. The classic marker of an engine running rich is black smoke. Even if it is not running rich enough for black smoke, the exhaust will have an unpleasant "smoggy" smell since it is emitting a lot of unburned hydrocarbons. And if you do have to decide about the head gasket because you took the head off (or just remove and inspect the spark plug), you will see loose sooty carbon.
While I am quoting proverbs, and this time will be my last comment on the reuse of head gaskets, another one states that "[t]here are none so blind as those who will not see." Post graduate diploma or not, if I have never had a head gasket failure from a reused head gasket and apparently TobyU has had similar experience, you are simply denying facts if you will not admit that a head gasket in good condition on a B&S L-head engine is likely to be good enough to work. True it will not seal as well as a new one, but it does not need to seal that well.
While I am quoting proverbs, and this time will be my last comment on the reuse of head gaskets, another one states that "[t]here are none so blind as those who will not see." Post graduate diploma or not, if I have never had a head gasket failure from a reused head gasket and apparently TobyU has had similar experience, you are simply denying facts if you will not admit that a head gasket in good condition on a B&S L-head engine is likely to be good enough to work. True it will not seal as well as a new one, but it does not need to seal that well.
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