This is my first time working on a marine motor this size. I have rebuilt many small engines, but am more of a hobbyist.
I have a pull start motor that fires, but one of the cylinders fills up with fuel at the reed valve after the crab. Either simultaneously the carb will end up with fuel coming out of the air inlet. I have to open coke to let it out. The cylinder that fills is on the left when facing the engine from the boat. At least that was the last time I checked. I should note that the boat was on a tilted surface so liquid would flow to that side. Ive replaced the spark plugs and have them set at 0.03, have 50:1 fresh mix. Engine starts and runs when the carb is off and most of the gas is cleared and a small amount sits on both sides.
History
I initially thought it was the carb. I cleaned and rebuild the entire carb float and all. I tried to set the float so it was parallel horizontally with the carb when upside down. I seem to have a more firm bulb. After rebuilding the carb I attempted to start the engine. It fired but stopped running after a few seconds. I realized the choke had slid in after it died. I could not get it restarted as usual with this fuel problem.
I then removed the carb and checked for fuel at the valve, and did not see any. I removed the carb because there was fuel coming out of the inlet as usual. I checked the rebuild and found I forgot the center seal. Put it all back together and I got it to fire but not start. Fuel out of inlet again and wont start. I have not removed the carb a third time since I am trying to not disturb the new seal I put on.
I do have spark but do not know compression. The engine was running during the weekend when it began refusing to start. Had a month old gas in it when we first started it at home. Started without much trouble and ran fine. Took it out fishing and began having problems. Started at the dock, but died shortly after and had a heck of time s tarting it. Once running seemed to be going good. Then it began to die after a few minutes of run time. Would start back up no problem. Figured bad gas but pressed on. Put new gas in with a 50/50 mix old/new. Now it has new gas.
The next day we could not get it to start and the work began. Found a loose bolt when the cover was taken off. Turned out to be from the head cover. There was also exhaust staining on the lower half of the engine. I ended up tightening two loose bolts on the head as well. Looked at the cylinder wall through the spark plug hole. Top cylinder seemed good but had 1 slight score mark. Bottom cylinder where the loose bolt was. Had a lot of carbon built up on the piston head and cylinder wall.
I also replaced a fuel line to the filter because it was cracked and allowed air into the line. Filter was clean. The carb was also relatively clean but the needle had a red seal looking material that was disintegrating. The new needle did not have the same feature. I will check compression tomorrow on both cylinders.
I have a pull start motor that fires, but one of the cylinders fills up with fuel at the reed valve after the crab. Either simultaneously the carb will end up with fuel coming out of the air inlet. I have to open coke to let it out. The cylinder that fills is on the left when facing the engine from the boat. At least that was the last time I checked. I should note that the boat was on a tilted surface so liquid would flow to that side. Ive replaced the spark plugs and have them set at 0.03, have 50:1 fresh mix. Engine starts and runs when the carb is off and most of the gas is cleared and a small amount sits on both sides.
History
I initially thought it was the carb. I cleaned and rebuild the entire carb float and all. I tried to set the float so it was parallel horizontally with the carb when upside down. I seem to have a more firm bulb. After rebuilding the carb I attempted to start the engine. It fired but stopped running after a few seconds. I realized the choke had slid in after it died. I could not get it restarted as usual with this fuel problem.
I then removed the carb and checked for fuel at the valve, and did not see any. I removed the carb because there was fuel coming out of the inlet as usual. I checked the rebuild and found I forgot the center seal. Put it all back together and I got it to fire but not start. Fuel out of inlet again and wont start. I have not removed the carb a third time since I am trying to not disturb the new seal I put on.
I do have spark but do not know compression. The engine was running during the weekend when it began refusing to start. Had a month old gas in it when we first started it at home. Started without much trouble and ran fine. Took it out fishing and began having problems. Started at the dock, but died shortly after and had a heck of time s tarting it. Once running seemed to be going good. Then it began to die after a few minutes of run time. Would start back up no problem. Figured bad gas but pressed on. Put new gas in with a 50/50 mix old/new. Now it has new gas.
The next day we could not get it to start and the work began. Found a loose bolt when the cover was taken off. Turned out to be from the head cover. There was also exhaust staining on the lower half of the engine. I ended up tightening two loose bolts on the head as well. Looked at the cylinder wall through the spark plug hole. Top cylinder seemed good but had 1 slight score mark. Bottom cylinder where the loose bolt was. Had a lot of carbon built up on the piston head and cylinder wall.
I also replaced a fuel line to the filter because it was cracked and allowed air into the line. Filter was clean. The carb was also relatively clean but the needle had a red seal looking material that was disintegrating. The new needle did not have the same feature. I will check compression tomorrow on both cylinders.
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