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Yamaha F60 Not running Smooth At High RPMS Out of Water?

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N320AW

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Just curious. I have an F60 with about 10 hours on it since new. Was just out flushing and running the engine in the yard. Runs great, but I noticed when I placed it in gear (forward) and got the RPMs up to about 4500-5000 the engine started to "buck" just a little. Never noticed this on the lake. In nuetral, at the same power setting, it was very smooth.

Is this anything I should take note of or just forget it and have a good time?

Thanks
 
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Some of these motors are smart enough ( computor or ECU ) to know that there are abnormal conditions and they will prevent YOU from damaging the motor.-------------Bottom line is " do not wind it up running on a hose " if you want your motor to last.
 
Because of the responses here, I called my marine service shop for more clarification on this. The lead mechanic stated
they have been running/servicing these motors for 16 years, using the hose attachment, and have NEVER had any problem whatsoever!

If someone can show proof that using a hose to the flush attachment is detrimental to this engine . . . I would like to hear it!
 
N320AW said:
Because of the responses here, I called my marine service shop for more clarification on this. The lead mechanic stated
they have been running/servicing these motors for 16 years, using the hose attachment, and have NEVER had any problem whatsoever!

If someone can show proof that using a hose to the flush attachment is detrimental to this engine . . . I would like to hear it!
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Using the hose to flush your engine is fine. Revving your engine to 5000 rpms on the hose unloaded is bad.
 
[email protected] said:
I am sure your lead mechanic will agree with Chris.Sorry we got you wound up on this one,but it was too hard to resist.Happy boating.Regards Pieter.
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Thanks for that. I'm a first time boat owner (G3 Eagle 176 Vinyl). I want to take good care of this outfit, but when someone basically says " if you haven't ruined your engine " or something like that, my hackles go up as anyone's would.

My prop, on our 4th lake outing, has already hit a piece of wood. Had to replace the prop myself. A good gash in one blade with wood splinters crammed into it. Haven't had the boat back out due to thunderstorms and very hot weather. I hope the prop doesn't spin off when I do!!!!!

Anyway, thanks to you all for the tongue and cheek help. I'm sure I'll be back with more questions.
 
N320AW said:
Thanks for that. I'm a first time boat owner (G3 Eagle 176 Vinyl). I want to take good care of this outfit, but when someone basically says " if you haven't ruined your engine " or something like that, my hackles go up as anyone's would.

My prop, on our 4th lake outing, has already hit a piece of wood. Had to replace the prop myself. A good gash in one blade with wood splinters crammed into it. Haven't had the boat back out due to thunderstorms and very hot weather. I hope the prop doesn't spin off when I do!!!!!

Anyway, thanks to you all for the tongue and cheek help. I'm sure I'll be back with more questions.
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I am no mechanic but decent with motors and such. There are several problems with running a outboard on muffs at a high RPM. First is that the motor depends on the restiance of water against the prop to keep it at a safe max RPM. When the prop is in the air, it can overrev and "redline" your motor and that equalls bad news for the pistons and crank etc. Many feel that the muffs do not supply enought water at high rpms to cool the motor though I do not know if this is true. One other thing is that the motor exhausts through the prop. When it is in water, a certaing amount of back pressure is generated that effects the motors running. On muffs there is greatly reduced back pressure and so it can cause a motor to run differently than when in water. Plus running a motor with the real prop and not a test prop is a great way to have a bad accident. Spinning sharp blades at knee to ball height is loads of fun. Add in some beer and rum for a fun friday night. Keep it to a high idle and you will be fine.
 
swampland said:
I am no mechanic but decent with motors and such. There are several problems with running a outboard on muffs at a high RPM. First is that the motor depends on the restiance of water against the prop to keep it at a safe max RPM. When the prop is in the air, it can overrev and "redline" your motor and that equalls bad news for the pistons and crank etc. Many feel that the muffs do not supply enought water at high rpms to cool the motor though I do not know if this is true. One other thing is that the motor exhausts through the prop. When it is in water, a certaing amount of back pressure is generated that effects the motors running. On muffs there is greatly reduced back pressure and so it can cause a motor to run differently than when in water. Plus running a motor with the real prop and not a test prop is a great way to have a bad accident. Spinning sharp blades at knee to ball height is loads of fun. Add in some beer and rum for a fun friday night. Keep it to a high idle and you will be fine.
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Thank you for that. You stated exactly what my mechanic said about the lack of back-pressure. Although he didn't
make a big deal about it . . . he said that he has never had any problems with running thousands of engines in the shop this way and he is one hell of a good outboard mechanic!

I may have overstated my situation on running the engine at high RPMs. It was only for about 10 seconds or less when I noticed the slight skipping of the engine. I figure its no big deal anyway. However, I do thank everyone who chimed
in on this.
 
Suzuki 4 strokes when in nuetral ( no load on the motor ) activate a switch.-----With this switch activated the engine control unit will not allow it to run above say 2500 / 3000 RPM.------------------When in the driveway and the motor is in gear ( still no load on it ) you should not wind a motor up !
 
racerone said:
Suzuki 4 strokes when in nuetral ( no load on the motor ) activate a switch.-----With this switch activated the engine control unit will not allow it to run above say 2500 / 3000 RPM.------------------When in the driveway and the motor is in gear ( still no load on it ) you should not wind a motor up !
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Racerone is correct Your mechanic is an idiot if he runs engines up to max rpm on a set of muffs.
 
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