That is a classic symptom of a blocked jet in the carb. If your friend is
handy, the carb needs to be cleaned good, especially the jet (bowl nut) with
a thin stiff sttel wire to open any clogged holes.

Also at the end of season, let the unit run until it uses all gas in the
tank and carb, to prevent future clogging from stale gas.
"Scott Adams" wrote in message
nk.net...
I'm trying to do a good deed for my neighbor, who can't get their
lawnmower
started. It's a Toro 20700 walk behind. After priming, it would start
and
run for only a second.

Is there a service manual out there I can download?

Thanks,
Scott