2007 Yamaha F50 RPM problem

[Roninramirez]

Boat and engine: 2007 Yamaha F50 on are Lund Rebel 1625XL

 

Puchased date: March 2009

 

Problem: We started noticing a high pitch metal to metal sound coming from the engine at WOT. We had a look at the user manual and the recommended rmp is between 5000-6000. The rpm @ wot(wide open throttle) is running @ 7000+rpm

 

We just bought this boat at the spring fishing show brand new, expecting no problems and ready for normal use. But to find out that there is a problem. This really questions the integrity of the dealerships trust.

 

If anyone has any information about this problem please respond.

[BITEME]

Whats the oil look like and if it is that bothersome take it in

[wallyboss]

Most boats bought straight form the dealers might not have the perfect prop for it. Which might cause the Over rpms. Firstly you should make sure that the motor was installed at the right height(anti-ventilation plate level with bottom of the boat) then you go out get the boat properly trimmed and WOT and check your rpms And depending on how high or low compared to the motor manufacturers Max RPM then you might have to change the prop pitch. Adding 1" of pitch to a prop will drop the rpms by about 200. You want to run your motor at the max rpms when you are going WOT.

 

Tha sound though is it just regular over revving sound or sounds like something is wrong????

Edited July 2, 2009 by wallyboss

[Dara]

The tach could be wrong too, mine was.

Check out the noise though.

[fisher]

Not sure if this is applicable but did you work in the engine when you first used it or did you hammer it right off the bat?

 

I read somewhere that the way you treat a new/rebuilt motor for the first 10 hours is the way it will treat you the next 10 years.

[musky66]

My Yamy 115 cuts out at 6100rpm, rev limiter for safety I guess.

[Dara]

My Yamy 115 cuts out at 6100rpm, rev limiter for safety I guess.

 

 

They told me that I Couldn't over rev mine too.And it had the right prop, thats why they checked the tach

[sonny]

Sounds like the wrong pitch prop...i couldn't over rev mine if i tried unless it's trimmed to high

[Roninramirez]

Thanks for all the replies,

 

We called the dealership about the problem. And it seemed that the RPM gauge was set wrong and needed to be adjusted. So were going to test it out on Sunday. Hopefully it will work.

 

But it still doesn't explain the high pitch cylinder sound that comes and goes at WOT. The motor was a 2007 factory refurbish that still has 1 year warranty remaining. Plus 2 years with the dealer.