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1974 115 fuel problems

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Turkeyhunter75

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I have a 1974 johnson 115 that is flooding the number 3 cylinder. Compression is good in all cylinders, carbs have been rebuilt, reed valves checked, new fuel pump put on, all fuel lines replaced and the number 3 cylinder still floods!! The number two cylinder is on the same carburetor and it's not flooding. I've been told by my local boat shop that it has to be in the carburetor. Anyone have a idea of what could be going on with the carburetor that would make it flood one cylinder and not the other? I'm at my wits end with this thing. I've got to much invested to just give up. I'd appreciate any ideas. Thanks!
 
How did you determine that # 3 is " flooding " on this motor ?----Is the high speed jet in place for # 3 cylinder.----# 3 is the lower cylinder on the starboard side.------What are the actual compression numbers ?---Does spark jump a gap of 7/16" on all 4 leads , yes or no ?
 
racerone said:
How did you determine that # 3 is " flooding " on this motor ?----Is the high speed jet in place for # 3 cylinder.----# 3 is the lower cylinder on the starboard side.------What are the actual compression numbers ?---Does spark jump a gap of 7/16" on all 4 leads , yes or no ?
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The motor floods out when idleing. When checking spark plugs all plugs are dry except the number 3 plug. The high speed jet is in place. Compression is 119 on number 1 cylinder, 120 on number 2, 118 on number 3, and 120 on number 4. I do have strong spark on all cylinders.

Also replaced stator and ignition control board. Moved coil from number three to number four and number three still ends up wet.
 
Checked reed valves ?----Replaced sparkplug boot on # 3 cylinder ?----Test run at night to look for spark leaking where it should not ?
 
racerone said:
Checked reed valves ?----Replaced sparkplug boot on # 3 cylinder ?----Test run at night to look for spark leaking where it should not ?
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No spark showing up where it shouldn't be. Boat will crank and run a few minutes and then it will die. When it dies it's not going to crank again for some time. It won't even act like it's going to start. Won't hit at all or if it does hit it's just a time or two. Doesn't idle well when it is running.
 
????------The top carburetor feeds # 1 and # 2 cylinders.----The bottom carburetor feeds #3 and # 4 cylinders !!----Does spark jump the 7/16" gap , yes or no ?
 
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The gasket for the bottom carb bowl could be creating a blockage. If it’s not perfectly placed it might cause more or less fuel to get to that cylinder through that jet.
 
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