Honda 115 suddenly running loud

[Swede19]

I have a 2007 Honda 115 outboard. Was out on the weekend running it 3/4 full throttle and suddenly it sounded like a 2 stroke and was running loud and hard. I dialed it back to 1/4 throttle and it seemed to come down to normal. I didn't try and take it back out. Any thoughts?

 

[jgmo]

Hi,
I don't know but your description makes me think possible exhaust leak.

I see there is a large gasket that could fail. I don't know how easy access is for you to inspect for that but it might be worth a look.

Honda Outboard 115HP OEM Parts Diagram for Exhaust Pipe | Boats.net

Buy OEM Parts for Honda Outboard 115HP Exhaust Pipe Diagram

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[jgmo]

Another area that can make plenty of noise is the intake.

If a duct hose came loose from the throttle body or air intake box (muffler) it could get loud too. They call it a muffler for a reason.
See items 5, 6, 7, in link.

Honda Outboard 115HP OEM Parts Diagram for THROTTLE BODY | Boats.net

Buy OEM Parts for Honda Outboard 115HP THROTTLE BODY Diagram

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[Swede19]

Another area that can make plenty of noise is the intake.

If a duct hose came loose from the throttle body or air intake box (muffler) it could get loud too. They call it a muffler for a reason.
See items 5, 6, 7, in link.

Honda Outboard 115HP OEM Parts Diagram for THROTTLE BODY | Boats.net

Buy OEM Parts for Honda Outboard 115HP THROTTLE BODY Diagram

www.boats.net

Thanks so much for your assistance! I will check both and report back!

 

[bobmech]

Have you tried trimming the motor in/down?
If the motor is trimmed out/up too far it will be louder than normal due to the exhaust exiting the water directly

Bob.