Optimax 2006, 90hp s/n-1B319762
Greetings, TIA for any input. My issue with the motor is low idle and an intermittent studder and engine cut out at 600rpm. At 650 it still studders but will stay on. At 850 it studders much less frequently and will not shut off. I replaced the Fuel filter (which was discolored and absent of water), replaced air filter and put 2 cans of sea foam in about 24 gallons of fuel. I do have about 8" of gray fuel line spliced downstream of bulb. Line is rock hard. I know not to replace with auto parts line. The od is 1/2 " but I'm not sure of the barb. Pulled plugs that are 2-3 yrs old and did have dry carbon on them and 1 plug had a piece of loose carbon between the firing pin and top horizontal bar. Sorry about that discription. Cleaned them and put them back in. All this was done before the rpm data. Regarding Guardian my question is does it go into protection mode limiting rpm to 2200? When I was checking rpm I was docked and was increasing throttle and have since read here that that is not recommended (neutral overspeed). Can it go into guardian mode without any beeps, because it never did beep. I wasn't sure how to reset the mode or that it could possibly be causing the underev so I left the lake. I do have the ear muffs and a single fluid filled gauge (0-160)to check pressures which I have not done. Hope this provides adequate information.
Thank you,
Richard