mriley4955
New Member
Stats: 96 SPX, Mikuni BN-38l Carbs
During the rebuild (OEM parts), I noticed a little blow by in the needle valve assembly area. When I did a pop-off test, it only got to about 25-30 psi and I noticed bubbles (used WD-40) around the need valve area. Also the carb would not hold pressure at 4 psi like the manual states.
I disassembled and reassembled both carbs several time, making sure everything was clean.
I should mention I removed the fuel tank and cleaned it. Replaced all fuel lines as well as the fuel selector valve. When I reassembled everything, I pressurized the fuel system and the ski started, however subsequent attempts the ski would not start.
I'm suspecting the lead down on the carbs but I don't know where to look for the leaks.
I have scoured the threads and I'm sure I have used OEM diaphrams (red dot) and the spring and needle valves are set properly. I'm not sure about the o-rings on the needle valve. I went to my dealer and got new o-rings and they seem to seat better than the rebuild kit but I still think I have some leakage. I just don't know if this is causing the failed starts.
Thanks for your consideration.
During the rebuild (OEM parts), I noticed a little blow by in the needle valve assembly area. When I did a pop-off test, it only got to about 25-30 psi and I noticed bubbles (used WD-40) around the need valve area. Also the carb would not hold pressure at 4 psi like the manual states.
I disassembled and reassembled both carbs several time, making sure everything was clean.
I should mention I removed the fuel tank and cleaned it. Replaced all fuel lines as well as the fuel selector valve. When I reassembled everything, I pressurized the fuel system and the ski started, however subsequent attempts the ski would not start.
I'm suspecting the lead down on the carbs but I don't know where to look for the leaks.
I have scoured the threads and I'm sure I have used OEM diaphrams (red dot) and the spring and needle valves are set properly. I'm not sure about the o-rings on the needle valve. I went to my dealer and got new o-rings and they seem to seat better than the rebuild kit but I still think I have some leakage. I just don't know if this is causing the failed starts.
Thanks for your consideration.
