I have a 1999 90Hp 4 Stroke Mercury. Last Aug every thing went with out incedent getting engine ready for annual fishing trip fresh oil, gas etc.it ran fine on the muffs.1st day of trip put the boat in the water it started right up and was warming up wiating for my fishing partner to get back to the ramp. The engine started to load up and finally flooded out bad took the boat to the nearest merc dealer called and said that the #3 carb had a needle and seat that wouldn,t seal .They got a needle and seat said they flushed the other carbs it was finally ready on the afternoon of the last day of the trip due to part avalability I noticed no new oil and filter was billed and asked about oil contamination from fuel was told no problem I cked it anyways when I arrived back at the resort it looked fine and no gas odor was detected.It started right up it idled about 150rpm slower than it used to @850 did not think to much about that though. about 20 min later going from one fishing spot to another there was a noise like something was hit pulled the throttle back immeaditly heard the alarm going off and shut it down #4 rod broke shrapnel everywhere plug was dry&white rest were tan getting the runaround and no anwsers as to WHY??!!
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