Hopefully you guys can help me pinpoint my boats issue:
The boat idles very low (starts at about 800 rpms) and slowly decreases rpm’s to the point that it stalls.
As long as I have owned the boat, it has idled lower then it was supposed to. Always around 700-800. But, it held the idle and never stalled. It was difficult to re-start at times...unless I used the steering throttle to bring a little extra throttle into the game.
I burned out a voltage regulator and this is what was repaired and checked when brought to the shop:
-new Stator and triggers installed
-new batteries
-compression verified by mercury tech
-newer fuel filters
-new plugs
-internal fuel filter cleaned out
-fuel pressure verified by Mercury tech
Boat held idle on the hose for the Mercury techs at 1100. Put the boat on the water where it idled up normal. It then slowly began to decrease in idle to the point where it will stall if I dont get in the throttle quick enough.
Long story short after some research, I experimented with disconnecting the port side head temp sensor while it was running and about to stall. The engines rpm’s came up immediately to around 1100. I could then plug it back in and the rpm’s hold and the idle would smooth. I could stop and restart and it would idle smoothly and maintain rpm’s.
Now if I let the boat sit and cool, when I go to start, the same idle issues as before would be present. Low rpm’s that gradually would result in it stalling. The idle was also rough with what sounds like misses. Unplug the port head sensor and everything works again. I have repeated this numerous times with the new and old head temp sensor. Both appear to have the correct ohms based on the temp.
I feel like I am close to figuring this out. Does the pattern of unplugging the port temp sensor and getting better idle performance mean anything? Any help would be great. Lastly, the mercury tech said that all of the sensors were within normal limits as well. Thanks
The boat idles very low (starts at about 800 rpms) and slowly decreases rpm’s to the point that it stalls.
As long as I have owned the boat, it has idled lower then it was supposed to. Always around 700-800. But, it held the idle and never stalled. It was difficult to re-start at times...unless I used the steering throttle to bring a little extra throttle into the game.
I burned out a voltage regulator and this is what was repaired and checked when brought to the shop:
-new Stator and triggers installed
-new batteries
-compression verified by mercury tech
-newer fuel filters
-new plugs
-internal fuel filter cleaned out
-fuel pressure verified by Mercury tech
Boat held idle on the hose for the Mercury techs at 1100. Put the boat on the water where it idled up normal. It then slowly began to decrease in idle to the point where it will stall if I dont get in the throttle quick enough.
Long story short after some research, I experimented with disconnecting the port side head temp sensor while it was running and about to stall. The engines rpm’s came up immediately to around 1100. I could then plug it back in and the rpm’s hold and the idle would smooth. I could stop and restart and it would idle smoothly and maintain rpm’s.
Now if I let the boat sit and cool, when I go to start, the same idle issues as before would be present. Low rpm’s that gradually would result in it stalling. The idle was also rough with what sounds like misses. Unplug the port head sensor and everything works again. I have repeated this numerous times with the new and old head temp sensor. Both appear to have the correct ohms based on the temp.
I feel like I am close to figuring this out. Does the pattern of unplugging the port temp sensor and getting better idle performance mean anything? Any help would be great. Lastly, the mercury tech said that all of the sensors were within normal limits as well. Thanks
