2006 - 90 HP Johnson - Symptoms are 1 - When punching throttle it will go to 5000RPM and then immediately drop down to 4200RPM, 2 - If you pump the fuel bulb RPM increases to 5200RPM and will stay there as long as you pump bulb. 3 When running at 4200RPM if you go over some waves it will go up to 5200RPM. Things that were tried. 1 - Runs the same on Boat tank and external tank 2 - Replace VRO pump 3 - Vapor pump rebuilt 4 - Vapor Separator cover replaced. 4 - Pulse limiter replaced 5 - Vacuum hose to vro -pulse limiter replaced. 5 Needle valve in Vapor Separator replaced. 6 - All Clamps checked - 7 All Hoses checked 8 - New fuel filter. Carburetors were rebuilt before I purchased boat (I know that does not mean they were rebuilt correctly). Motor always runs the same, I can replicate any of these issues at any time.
