Hi
I have a '90, 130 hp Yamaha outboard. It stumbles or cuts out during sustained high speeds. It also runs rough at about 5 mph but that may be normal for a 2 stroke. It has loads of power when the throttle is first opened but within a couple of minutes it starts to stumble or cut out and the rpm's drop somewhat. It does not stall. The problem got worse and it would not maintain a plane. I squeezed the primer bulb a couple of times and the problem improved greatly but it still stumbles.
It used to be a lot worse but on your advice I checked the fuel system and replaced tubing, leaking fuel pump, primer bulb, large external seperator, cleaned the internal filter. I have gotten to the carbs now. They were supposedly overhauled before I got it. One barrel on the top set leaks fuel from the float through the main jet when the primer bulb is squeezed hard. I pulled the top set and found new needle and pilot screws. The seats do not appear to be replaceable. The carb seems clean otherwise except for some residue near the leaking jet. I have not yet pulled the other carb set.
1- Could this be a/the problem or is it too small to worry about since I have to squeeze the bulb hard to get it to leak?
2- If it is a problem can the seat be honed or must the carb body be replaced? I assume that it leaked a lot worse before the jet was replaced. The local Yammy dealer says that there is no replacement seat available.
3- What is next if this would not cause the problem?
I really appreciate your help so far. Things really have improved a lot since I replaced the leaking fuel lines and pump. The thing is a blast to run when it works right! If I need new carbs I see that I can get them from you. I do not see a rebuild kit shown for this carb though.
Thanks
Rob/Kahoona
I have a '90, 130 hp Yamaha outboard. It stumbles or cuts out during sustained high speeds. It also runs rough at about 5 mph but that may be normal for a 2 stroke. It has loads of power when the throttle is first opened but within a couple of minutes it starts to stumble or cut out and the rpm's drop somewhat. It does not stall. The problem got worse and it would not maintain a plane. I squeezed the primer bulb a couple of times and the problem improved greatly but it still stumbles.
It used to be a lot worse but on your advice I checked the fuel system and replaced tubing, leaking fuel pump, primer bulb, large external seperator, cleaned the internal filter. I have gotten to the carbs now. They were supposedly overhauled before I got it. One barrel on the top set leaks fuel from the float through the main jet when the primer bulb is squeezed hard. I pulled the top set and found new needle and pilot screws. The seats do not appear to be replaceable. The carb seems clean otherwise except for some residue near the leaking jet. I have not yet pulled the other carb set.
1- Could this be a/the problem or is it too small to worry about since I have to squeeze the bulb hard to get it to leak?
2- If it is a problem can the seat be honed or must the carb body be replaced? I assume that it leaked a lot worse before the jet was replaced. The local Yammy dealer says that there is no replacement seat available.
3- What is next if this would not cause the problem?
I really appreciate your help so far. Things really have improved a lot since I replaced the leaking fuel lines and pump. The thing is a blast to run when it works right! If I need new carbs I see that I can get them from you. I do not see a rebuild kit shown for this carb though.
Thanks
Rob/Kahoona
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