Hey guys,
Looking for some advice on a F115 with 703 hours. The issue is it will idle low around 700 and 600 in gear. It will stall sometimes in gear at idle as well as throttling down from a run. It also hesitate slightly when hard throttling in or out of gear. No other issue with the motor, it will spin up to 5800 without an issue. I put a pressure gauge on the fuel rail and got the following. Measured 10 psi (manual calls out for 44.1) with the key turned on. I tried to build pressure by turning the key on and off a few times and was able to get it up to 30psi but it would not hold. At idle i would get 36 psi (manual calls out for 35.6). I also pulled the plugs and noticed plug from cylinder 1,3 and 4 are clean and dry. Plug from cylinder 2 is not fowled but wet. Compression test shows good compression, ISC valve is functioning as i can hear it resetting after shutoff and there is no stored code on the motor. All fuel filters and plug was replaced a year ago and all injectors was replaced two years ago (used OEM re-manufactured). Another thing to note is the boat did sit for almost a year.
My theory is injector 2 is leaking causing the plug to be wet and not building up fuel pressure with ignition on. However, the leak is irrelevant at higher RPM where fuel flow is greater than that of idling. Injectors will be replaced as they are still under warranty but i'm curious to see what you guys think.
Looking for some advice on a F115 with 703 hours. The issue is it will idle low around 700 and 600 in gear. It will stall sometimes in gear at idle as well as throttling down from a run. It also hesitate slightly when hard throttling in or out of gear. No other issue with the motor, it will spin up to 5800 without an issue. I put a pressure gauge on the fuel rail and got the following. Measured 10 psi (manual calls out for 44.1) with the key turned on. I tried to build pressure by turning the key on and off a few times and was able to get it up to 30psi but it would not hold. At idle i would get 36 psi (manual calls out for 35.6). I also pulled the plugs and noticed plug from cylinder 1,3 and 4 are clean and dry. Plug from cylinder 2 is not fowled but wet. Compression test shows good compression, ISC valve is functioning as i can hear it resetting after shutoff and there is no stored code on the motor. All fuel filters and plug was replaced a year ago and all injectors was replaced two years ago (used OEM re-manufactured). Another thing to note is the boat did sit for almost a year.
My theory is injector 2 is leaking causing the plug to be wet and not building up fuel pressure with ignition on. However, the leak is irrelevant at higher RPM where fuel flow is greater than that of idling. Injectors will be replaced as they are still under warranty but i'm curious to see what you guys think.