Hello,
I'm working on what appears to be late 80's 15hp 2 stroke. Sorry I don't have the exact information, it's not mine and I forgot to grab the serial code. Anyway initially the problem was the engine wouldn't start just crank over after sitting a week. Only started by spraying fuel into intake. Had fuel in the bowl. Turned out to be a clogged carburetor, specifically the needle jet passage. After cleaning the carb, it fired right up and sounded great. Except it would continually stall after 5-10 seconds of running, if you tried to give it gas it would just bog down like fuel starvation. I'm kind of out of ideas at this point, this is the first time working on a outboard and the only thing I could think of was maybe the flow of fuel wasn't enough. At first what I thought was some sort of metering block on the side of the carburetor is actually the fuel pump. I have no idea how this works but apparently has multiple diaphragms in it. It's part 44 here: http://yamahamc.partsandwarranty.com/SSIConverted/603416_140817_021917_5237.png
I opened it up while cleaning the carburetor but didn't know what it was so I screwed it back on, I only removed the outer cover. I'm wondering if maybe I mis-installed it? I tried re-installing it but it made no difference. I noticed that half of the black diaphragm? was wet while the other half was dry. I don't know if this is normal or possibly my issue. I've included a link of pictures. Any suggestions on where to start next?
Thanks
http://imgur.com/a/6yQOD
I'm working on what appears to be late 80's 15hp 2 stroke. Sorry I don't have the exact information, it's not mine and I forgot to grab the serial code. Anyway initially the problem was the engine wouldn't start just crank over after sitting a week. Only started by spraying fuel into intake. Had fuel in the bowl. Turned out to be a clogged carburetor, specifically the needle jet passage. After cleaning the carb, it fired right up and sounded great. Except it would continually stall after 5-10 seconds of running, if you tried to give it gas it would just bog down like fuel starvation. I'm kind of out of ideas at this point, this is the first time working on a outboard and the only thing I could think of was maybe the flow of fuel wasn't enough. At first what I thought was some sort of metering block on the side of the carburetor is actually the fuel pump. I have no idea how this works but apparently has multiple diaphragms in it. It's part 44 here: http://yamahamc.partsandwarranty.com/SSIConverted/603416_140817_021917_5237.png
I opened it up while cleaning the carburetor but didn't know what it was so I screwed it back on, I only removed the outer cover. I'm wondering if maybe I mis-installed it? I tried re-installing it but it made no difference. I noticed that half of the black diaphragm? was wet while the other half was dry. I don't know if this is normal or possibly my issue. I've included a link of pictures. Any suggestions on where to start next?
Thanks
http://imgur.com/a/6yQOD
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