During our ski trip this weekend I noticed the accelerator pump not working correctly. This is the first time this has occurred. The motor now acts exactly like many of my older cars when the accelerator pump needed replacing on the carb. The symptom on the Merc now is about a 2-second delay in actual power-up RPM increase when the throttle lever is pushed to WOT, but the power then (after the delay) is full and normal.<br /><br />We've had this motor several years and the fuel pump has been rebuilt twice and all the rubber lines have been replaced in the fuel circuit, including the accelerator pump circuit. However, neither the accelerator pump or check valves have ever been replaced. <br /><br />I believe, from what I feel in the controls, that the accelerator pump is the problem, but I've never had experience with this and I'm not positive. The reason I think it's the pump is that the linkage cam is still depressing the accelerator pump plunger like it always has, but now there is a noticed lack of increase in throttle handle tension as the cam depresses the plunger - - like no (or very little) resistance in the pump itself.<br /><br />I see a diaphram in the accelerator pump and am hoping that there might be a simple rebuild kit for this part??? <br /><br />The Merc manual shows the pump circuit but doesn't have any troubleshooting info for this circuit that I can find.<br /><br />All help really appreciated,<br /> Marty
