i have a 82' 750 E with CV34 carbs and i was doing some winter maintenance tonight when i noticed the my #3 spark plug was soaked with fuel.. again, and the piston was a little washed. This happen last year on the same cylinder. At that time i thought it was because i was running a vacuum line to #3 carb from the petcock. i think i was planning on rebuilding the petcock but just ended up removing the diaphragm,capped the vacuum ports and just let the fuel gravity feed ever since , the bike ran great all summer up until the last few rides when #3 started to miss.
last time i did the " clear tube test" to verify my float wasn't stuck. ... if this passes again. . does anyone have any suggesting on what to check next?
do you think this could happen if the carbs weren't vacuums synced correctly?
my number three cylinder is being over loaded with fuel, soaking the plug and into my exhaust system, clear tube test seem fine. i did find a fuel small holes in my vacuum diaphragm of the carb slide , would this cause?
Do a compression test with carbs in full throttle position. Remove all spark plugs for a better cranking.
Post the readings. A very low compression (no firing = un-burnt fuel) on #3 looks like a burnt valve or zero valve clearance.