goodforbrains
New member
Hi, I have a 1988 Nissan NS90A Same as Tohatsu M90A. The engine has been sitting for 3 years. I rebuilt the carbs with oem rebuild kits. I completely cleaned every port and passage. I did the link and sync as per the factory manual. In the manual, it says that any engine coming out of long term storage should use a tank of gas at 50:1. I cleaned the oil reservoir, put all new oil lines on and purged the oil pump. I am using Yamalube 2M 2 stroke oil. When I started the engine, it has a lean sneeze. will pop, and a puff of smoke comes out, then catches up to itself. I noticed fuel pouring out of the bottom carb. I took it apart to find the brand new float was full of gas. I thought I found my problem. I put one of the old floats back in after fully cleaning the carb again. I did the same to the other 2 carbs. Floats were fine but I took everything apart and cleaned them again. Reinstalled. Did a link and sync again. Same results. I get a lean sneeze. I checked the plugs, they are fine. They are brand new. Calls for b8hs10. I have br8hs10 in there. <br> The manual calls for 5 degrees after top dead center. If I hold the plate to 5 degrees BEFORE tdc, the engine runs great with no sneeze. I am really confused trying to figure out why it sneezes. Will double oil cause this? Using a resistor spark plug? After going over the manual again, it says to use 89 octane fuel. I didn't realize this and am running 87 right now. I don't think that would cause it, but maybe I am wrong. I want to put the boat in the water and go for a ride, but I don't want to burn a piston or do any damage. Any help or suggestions would be great. Maybe this engine just runs that way? Thanks to all for reading. By the way, the engine runs great at higher rpms. Just not at idle. Compression is at 120 for each cylinder also.