have a cub cadetsc500 21 inch electric start mower with the following engine 2P70MU have cleaned carb it will start and run for a few seconds acting like not getting gas, so put a new carb on it and it does the same thiing, will not stay runnung like it is not getting gas 
any help would very greatful thank in advance
AC
	
		
			
		
		
	
			
			any help would very greatful thank in advance
AC