gas supply flow rate question

[iron and steel]

hello to all i have been working and fixing my 85 maraton . did the top end over haul last fall and the engine runs but ive been haveing problems recently with the cart cruising for a while and then just stops running and just cranks i have cleaned the carb and replaced the electic fuel pump and it runs im just wondering about the fuel rate because in the past i have just turned it on and off as needed but i want to install a flow rate thingie any one have any thing on this . or is it even the fuel pump help me wise ones . ill post before and after pics when i get home this evening