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Ask Dominick Your Own Question
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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Yamaha 115 HP Four Stroke. Engine devlopes only 5200 RPM's

Customer Question

Yamaha 115 HP Four Stroke. Engine devlopes only 5200 RPM's at full throttle with top speed under 30 mph. Prior to problem Engine hit 6000 RPM's and would do 50 - 55 mph at full throttle. I put in a gas line water separator filter canister, new fuel, and fuel additives to clean injectors. None of that worked. I never used fuel with ethanol in this engine. The motor has a 4 blade high performance prop. Now I can barely get a 120 lb. water skier up and top speed is only 20 mph at full throttle towing the skier with the driver and one spotter in the boat. My mechanic says "get a new prop", the old one is "slipping". I don't think he's right. Is there another option??
Submitted: 1 year ago.
Category: Boat
Expert:  Jason replied 1 year ago.

Hi Tom, my name is Jason.

Have you changed all of the fuel filters inside of the engine itself yet?

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