I have a kind of similar problem with my Izy.
I have had mine for about 6-8 years and it has always started first time every time. Usual operating procedure for mine has always been, cold start on choke, run on full throttle, close throttle, engage brake, then to restart put back to full throttle.
However this year it started refusing to warm start whilst warm unless I used choke, also it now stalls on closed throttle. Although on full throttle it still seems quite capable of cutting the lawns.
I have tried all these tricks so far
-Replaced air filter
-Replaced spark plug
-Replaced fuel
-Ran on high concentration Redex
-Poured Redex directly into Carb.
-Put Carb cleaner through Carb.
It will now sometimes warm start without choke but still will not tickover on closed throttle.
Ideas anyone?
Cheers
Baz
Baz
July 2012