got a 79 1/2 mercury 90 hp that was my dads RIP. he had carbs rebuilt at a shop last year an took it out on lake fuel pump went out he gave up on it. so we have the boat now we rebuilt fuel pump an put new bulb fuel lines new ends on tank an motor still would not start unless we sprayed fuel oil mix in the carbs. took it out on lake ran decent but not perfect so we put it in a shop to have carbs rebuilt the mechanic called an said all 3 main jets where gone is this possible for the motor to run without the mainjets. an would that explain why we had to spray carbs everytime to start motor. tks once again..