90 hp two stroke missing on third cylynder

[tankkd01]

changed plugs, changed coils, rebuilt carbs., checked compresson, but still number three missing am i missing something?

[throrope]

How is the rest of the fuel system? I lost a cylinder, went through the carbs, got it back, then lost it again in twenty minutes. Turns out the fuel system was contaminated. For less the the cost of disposing of the gas, I replaced the tank along with the entire fuel supply. Now I empty the boat of all fuel between trips. For me, no gas means no gas to go bad.

[TownsendsFJR1300]

Is the #3 spark plug actually firing? Pull it, hook it to the wire and ground it on the block. Crank and inspect for spark. (I'm assuming you DON"T have a spark plug checker which would be easier/safer)

Can you drain carb #3 and catch what comes out? As noted above, the carb could have crap back in the jets. Did you actually pull the main and idle jets and physically look thru them? A spray of carb cleaner alone DOES NOT COUNT..

Cranking the engine up (on muffs with water) then checking to see if the spark plug is wet(we're looking for fuel).