Question84 nighthawk 750 s cylinder # 3 is wetting the spark plug, inconsisitently, seems to come and go. and after a brief ride, fuel smelling liquid drips from thecranckase vent tube . i assume that 1 coil serves 2 spark plugs, and if it was an ignition issue, it would show in 2 cylinders, only 1 plug is wet. Is it possible to remove the fuel bowl without removing all the carbs? I feel that the float for that cylinder may be sticking.
Thanks, Frank
AnswerFrank, unless you have some good small angled Phillips head screwdrivers with a 90 degree driver, like:
http://www.ebay.com/itm/Motorcycle-Tool-Air-Mixture-Carburetor-Pilot-Screw-Adjus Ebay number 200770570607 is something that can work in that small space.
then you probably should pull the carb rack and really clean up everything inside the float bowls. Sometimes the float bowl screws are VERY tight if they have never been removed before, so even the trick tool may not work.
Raw fuel smells and dripping from the float bowl overflow tubes does indicate a drooling/leaking float valve.
The coils feed 1-4 and 2-3 cylinders. I would check the spark plug caps to see if they are still around 5k ohms and tightly connected to the plug wires.
Make sure that the fuel tank is clean, the petcock screen is clear and there is no debris or rust particles floating around the fuel system. The bike is 28 years old and probably needs some serious checking over in all systems.
http://www.cmsnl.com/honda-cb700sc-1984-nighthawk-s-usa_model1018/partslist/E++1 for carburetor drawings and part numbers.
Bill Silver
