I have a 90 Mitsubishi, the plugs foul real fast, last about a month. And my gas mileage sucks, am thinking that the fuel mix is set too rich. It also floods easily. How do I adjust fuel mixture? As I am not a mechanic, if you could post a picture of the carb to indicate where to adjust it would be helpful. Thanks
I would start by checking the choke system. Make sure the butterfly for the choke is opening once the engine has been started. We have coolant activated chokes on these engines. You will have to pull off the air cleaner hose to observe this activity when you start it up. Engine should be cold. If it doesn't open up (or is totally closed without the 5mm space between the butterfly valve and the carb throat you need to adjust the static resting point so that is the space). If the butterfly valve doesn't open up within about 1-1.5 minutes I would suspect a coolant hose problem. Also, while you have the air cleaner hose disconnected check you air cleaner element. If none of this leads anywhere next would be timing check, then compression check to see if the fouling is oil leakage in the heads or rings. Does it smoke when you run it? If not good. If it does, that is a clue it is oil related not choke.
