Motorcycle Repair: LEAKING CARB, bill silver, float valve

Question
I HAVE A '97 HONDA NIGHTHAWK I RECENTLY PURCHASED, WHEN I FIRST GOT IT I NOTICED IT WAS MISSING ON THE #3 CYLINDER. I REMOVED ALL BODY PARTS TO HAVE PAINTED, WHILE THEY WERE OFF I REPLACED SPARK PLUS AND WIRES. WHEN I REINSTALLED ALL THE BODY PARTS BACK ON THE BIKE (AFTER ABOUT 2 WEEKS IN THE PAINT SHOP) I COULD NOT GET THE BIKE STARTED, AND FUEL WAS LEAKING FROM THE #3 CARB. I'VE TRIED DRAINING THE CARB, THEN FILLING AGAIN, AND FLUSHING AGAIN, IT STILL WON'T START, AND IS STILL LEAKING. COULD THIS BE THAT THE FLOAT IS STUCK, AND ALSO COULD THIS HAVE BEEN WHAT CAUSED THE MISSING PROBLEM IN THE FIRST PLACE, OR JUST A COINSEDENCE.

Answer
Matt, the carb inlet could be blocked with dirt, rust or debris and/or the needle may have been stuck for some reason.
Usually when they leak like that you can tap on the bowl with a screwdriver handle and sometimes reset them, however from what you have described, it sounds like the bowl needs to come off for inspection and perhaps replacement of the float valve, if there is wear or damage to the needle. If you have enough room and a long thin screwdriver, you may be able to get bowl off with carbs in place and see what's going on in there.

If the bike has been sitting for awhile, the gas can gum up the carbs pretty good. Try Yamaha carb cleaner solution, mixed with gas in that case, otherwise they will have to come off for a good cleanup.

If the float has been leaking and fouling the plug, that would explain the miss on that cylinder. You might want to get a compression test done on all cylinders to make sure that there isn't a mechanical issue. These engines are long-lived, so that generally isn't a problem.

Bill Silver