in need of carburetor advice

[RAB5050]

when it comes to carbs, I am always scratching my head the darn things are so intricate. My 3600 has been running baby smooth until I started it for the first time this year. It ran fine then started to cough a bit and ran a bit uneven at idle and half throttle. I pulled the plug and it was all black with carbon but not thick,it cleaned up easily and I tried it again with the same result. The machine sat outside all winter with a half a tank of gas. What effect dose old gas have on engine performance? The motor dose not burn oil and it seems to still have enough power. Should I use an additive in the gas or drain the tank?
any input much appreciated,
RB

[bubba40]

Could easily be bad gas. If stored outside there could be moisture in the tank which would account for a rough runing engine. Definitely drain the fuel and start over with a fresh batch and take it from there.

 

[RAB5050]

ty I will take your advice and post a follow up
RB

[rattosh51]

RAB5050
Old gas can cause many problems, especially in carbs. Once you get some fresh stuff in there, I would definitely add some Seafoam, or other additive to run through the system and clean the internals. Once you run it through, you should see some improvement. If not, you may have to pull the carb and clean out the bowl and spray it down or soak it with carb cleaner. Main cause of problems in carbs is dirt. You'll be surprised how much crap is in the tank. Probably a good idea to change the gas filter too.

[RAB5050]

ok will do, I haven't heard of sea foam but I know it must be some kind of carb cleaner. ty for your advice and I will post a follow up
RB