RPM out of water

[mchristo63]

What is the proper way to run the engine when using a flush attachment? Meaning, is it only safe to idle, or is it ok to take the engine to a higher RPM. I don't have a temp gauge.<br /><br />Thanks<br /><br />1984 Mercury 35HP

 

[Laddies]

Re: RPM out of water

over 1500 your looking for trouble

 

[mchristo63]

Re: RPM out of water

Great, thanks. How about if the motor is submerged in a tank of some kind (trash can)?

 

[JB]

Re: RPM out of water

What Laddie means is over 1500rpm with no load on the prop. Thermal runaway is a real threat. That is why your throttle linkage is limited when in neutral.<br /><br />If you have it in a test tank and in gear it should be able to rev it, depending on the size of the tank and the HP of the engine.<br /><br />Anything over 5hp should empty a trash can in short order if revved in gear.<br /><br />Good luck.

 

[Nos4r2]

Re: RPM out of water

Just a thought, I accidentally knocked one of my motors into gear when flushing it in a trashcan last year and the thrust was enough to slam the can against the prop. Make sure that trashcan can't move!