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2002 Mercury 40 / 2-stroke /2 cylinder (klunking?)

H

Howmaster

Member
My 2002 Mercury 40hp /2 stroke / 2 cylinder that runs fantastic
and has compression of 125 in both cylinders. But , this summer it has a constant klunking noise while it's running at idle speed in forward or reverse. It's normal and super guiet when I do one of three things. #1. Put it in neutral. (Gone)
#2. Take prop off. Or #3. Give it roughly 200 additional RPM's
then its gone.
***The only thing I found is if the motor is OFF....in nuetral I can spin "by hand" the propeller left or right and it turns super smooth and gears clicking.
If I put the motor in forward, I can not turn the prop counter- clockwise but I can turn it clockwise smoothly with a rhythmic clicking.
NOW....if I put the motor in reverse, I cannot turn the prop
clockwise....(but I can't turn it counter-clockwise either and get
that rhythmic clicking.)
When the motor is running in a barrel....it goes into reverse just fine...but there is still the klunking sound running in forward and reverse.
The prop should spin by hand counter-clockwise by hand with a slight clicking,...correct?
i drained the lower unit oil...and it's super clean with no water and there is it any metal shavings on the drain plug.
Any ideas if the 3 things that make the klunking go away could be related to a reverse issue here??
 
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I can't move the prop(in reverse) by hand in either direction. The little bit it
does move (1/2") ....both ways you can see the flywheel moving
with it. I took the shift cable off and manually put it reverse, then
moved the shifter to the reverse position and the linkage and the cable
line up perfectly.(everywhere I read on the Internet that the prop should
spin freely with clicking in forward AND reverse!??)
 
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..." I read on the Internet that the prop should spin freely with clicking in forward AND reverse!??) "

Nope; only in forward.

Jeff
 
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