Just aquired this engine and need some help.<br />Model No 3732c<br />S/No c546078<br /><br />Done points gap 0.020<br />clean'd carb<br /><br />Engine now runs on chock only. when turn chock off engine rev's then die's???<br /><br />Wont to cheq the water pump, undid four boult's but box wont...