Gary Brown
New member
I have two 225 HP 1997 Mercury outboards, carbs. One will run 10 min @ 4000 RPM and then dies off slowly, then after rest for 15 min, will run again. Did that 5 times in a row in short succession. I have done the following: vacuum checked fuel lines including primer bulb back to tank; changed both fuel filters (canister and on top of carb); rebuilt the fuel pump, have 4 PSI @ carb @ idle; replaced the ignition switch; swapped ECM's, heat checked the crank position sensor and ignition coils; changed plugs; ohm checked the throttle position sensor; compression checked all 6 @ 135psi. Have not yet torn down the carbs. Runs in driveway for 1 hr no problems. Out of ideas, help!