35hp evinrude has me puzzled

ranger42

Seaman Apprentice
Joined
Mar 27, 2013
Messages
37
hey folks. I been working on a 1983 35hp evinrude. Rebuilt carbs. New fuel pump. But it continues to bog down at full throttle. Engine has good compression. Can’t find no bad or broke wires. When I removed the fuel line from carb spinn it by starter. After priming fuel to the pump. It shoots out 3 or 4 stream then stops pumping. I’m thinking it should continue to pump. Or does it need to be running to have enough vacuum to continue to pump. I checked all lines from carb to the sump. There air tight. So I’m thinking if it should continue to pump while spinning starter. Thin I must have a vacum leak. What you fellows think
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
38,881
The pump operates with crankcase PRESSURE pulse and not so much by vacuum.-------It should continue to pump when you spin the starter.------I would say there is a leak between the pump and fuel tank or INSIDE the tank on the pick up tube.-----How did this motor run for you last year ?-----Have you done a cylinder compression test ?----If so post the numbers.
 

ranger42

Seaman Apprentice
Joined
Mar 27, 2013
Messages
37
Engine has good compression don’t need to gauge it to know that fuel line is air tight from pump to the sump as I stated
 
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