I have an Ace Tecumshi-engine lawn mower that won't crank. I bought it at a
yard sale for 35 bucks, it had sat for a year or so unused until today.

It actually ran fine before but even then it was only after quite a bit of
time of trying, typically it would crank after you sprayed starter spray on
it & pumped the thingie 3 times, but then it wouldn't STAY cranked. It would
then cut right off.

Well after sometime it got to where you'd crank it & it would stay cranked,
you also could shut it off & restart it with no problems, and I cut a fair
amount of grass with it. Then the symptoms returned, and I'm still there.

There is still some gas in it, but not that much. One part of me thinks to
dump the old gas out and replace it with new, as the mower had sat for a
year or so prior to today. Then again it had exhibited those problems
previously with more gas in there than there is now, so it makes me think
that isn't it.

Tips?

LRH