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Fuel only on cylinder 1 and 3

C

cshanno199

New member
Hello

I have a Johnson 115hp 1976 model#115ETL76G. I have an issue where only cylinders 1 and 3 are getting fuel.(Right bank of cylinders from the back side). I know this because I have pulled out each spark plug on there own and spun the engine. When I did this no fuel spray came out of the cylinder 2 and 4. Looking into the carbs after spinning the engine I see fuel droplets on all four of the throttle plates. So I assume that fuel is being sprayed into the intake manifold. I'm not sure what would cause this issue. I have already replaced the fuel pump for a previous issue so that is working fine. Also the power pack has been replaced for spark so if there was fuel it would ignite. It has a dual carburetor setup that I did a rebuild on. Not sure which carburetor is in-charge of which cylinders.

Not sure what the problem could be.

Any help would be greatly appreciated.

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The top carburetor ( one bore ) feeds the #1 cylinder.-----The bottom carburetor ( one bore ) feeds #3 bore.----I would say you need to look at the carburetors again.-----So do you have spark that actually jumps a gap of 7/16" on each lead , yes , no or not sure why that should be tested like that.
 
Spary some fuel in the carbs with spay bottle...if it a fuel problem you will hear the cylinders kick in...my bet you have 1 and 3 flipped on pack as side by side. It will still have spark ..just at wrong time
 
faztbullet said:
Spary some fuel in the carbs with spay bottle...if it a fuel problem you will hear the cylinders kick in...my bet you have 1 and 3 flipped on pack as side by side. It will still have spark ..just at wrong time
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What do u mean by hear the cylinders kick in. Also what does "1 and 3 flipped on pack as side by side" mean. It has strong spark, I tested it with a inline spark tester.
 
racerone said:
The top carburetor ( one bore ) feeds the #1 cylinder.-----The bottom carburetor ( one bore ) feeds #3 bore.----I would say you need to look at the carburetors again.-----So do you have spark that actually jumps a gap of 7/16" on each lead , yes , no or not sure why that should be tested like that.
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I te ssd t ed d the spark with a inline spark tester and it has strong spark. This is my first 2 cycle outbard motor that I have worked on not familiar with these styles of engines. Is there anything internally between the carburator and the inlet to the cylinder that could cause issues?
 
If you bypass the carburetor with the spray bottle and the cylinders that weren't firing before start firing again, there's something wrong with the carbs. I don't know what he means with the flipped power pack, but it doesn't matter how strong the spark is if it's firing at the wrong time. An inline spark tester tests for continuity, but you need a spark gap tester to make sure there's enough juice. A 7/16" gap as racerone stated above.
 
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