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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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Engine SN: OW673430, mercruiser 5.0 MPI, drive serial num OW927662.

Customer Question

engine SN: OW673430, mercruiser 5.0 MPI, drive serial num OW927662. use boat in saltwater, engine is open cooled system using seawater for cooling. Temp are running between 185 and 205 on gauge on boat. Have recently replaced raw water impeller, thermostat, engine oil, plugs and drive lube. Motor running nicely, temps on top of riser are 90F, on side of manifold ~180, on bottom of manifold ~210-230F. Running at 3000RPM on plane temp ~185, when pull off plane it goes up to 195-200. When running at 3500RPM on plane temp is 195F or so. After 5min back down off plane and at 1000RPM temp drops to ~185. Not sure what to do/check next. Temps on manifold were from IR thermometer.
Submitted: 2 years ago.
Category: Boat
Expert:  Tan replied 2 years ago.
Hello.I would pull one of the risers and check for blockage in the manifolds and risers. Do you know how many hours are on the manifolds and risers?

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