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Dominick, Marine Mechanic
Category: Boat
Satisfied Customers: 1009
Experience:  25 Years Experience as Mechanic, 20 Yrs Boat Yard Owner/Mechanic, Factory Certified
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1996 merc 125 2+2. knocks when I get up to plane , about

Customer Question

1996 merc 125 2+2. knocks when I get up to plane , about 4k rpm .
New power head , new lu. Idle s fine no noise at any rpm no load.
Submitted: 2 years ago.
Category: Boat
Expert:  Jason replied 2 years ago.
Hello my name is ***** ***** am I speaking with? Sounds like a timing issue. What is the full throttle timing set to?
Customer: replied 2 years ago.
Dont know ( sorry , phone went out ) . How can I tell.. Has good power up to plane then rattles..
Expert:  Jason replied 2 years ago.
You wrote that it was a new powerhead. Did you install that or did somebody else install it? Do you have a timing light to check timing?

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