Welcome! Need support, you got it. Or share you ideas and experiences.
I have recently purchased a 2003 115 horse 4-stroke mercury engine for my crestliner. It seems to run very well, but I find when I am running 3/4 throttle or better and throttle down quickly, I hear a noise that sounds like a rattle coming from the lower unit. I heard this noise as well when I first picked up the motor and they ran it at idle with a water hose connected it. The dealer assured me it was normal and had something to do with back pressure. Has anyone else had this problem or can tell me what it is? Appreciate any help.
I haven't had that problem, but it sounds like slack (backlash)in the lower unit gears. There is little you can do about it. A solution might be to throttle down gently instead of quickly.
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