wheel horse round hood 753 ?

[wh1257 226]

hello
After a long search jester the problem of the engine I still have not found the problem I start him and he continues to run when fully up to temperature it is quiet I can still start him choke on it he remains therefore to rotate but after a time he also falls silent again and I get more hemniet started I have tried everything but have so far not found what the problem is
the engine is a 7 hp kohler model 753

who can help me looking for the problem?

Thanks vincent