Define "Pushing It Hard"

[fatpratt1996]

I hear you guys say to richen the fuel/oil mixture if you are going to push the motor hard. What I am wondering is, what is pushing it hard. When I first got my boat, '99 Astro w/'99 125 Merc, I would run it wide open at roughly 5000-5100 rpm's for 15-20 minutes at a time. Now I may bring it up that much for a minute or so and then back it off to about 4000. Is this needless or will it actually save me in the long run? Normally what kind of abuse can these motors take? An early thanks is in order.

 

[Terry H]

Re: Define "Pushing It Hard"

fatpratt, I too don't know what they mean, my interpritation is that if you have modified your motor to run with more power than it was designed to have, then ran it at 7k rpms alot in a racing situation that is what I would call "running it hard". I run my current outboard motor at wot on the Snake River for long periods of time, but she shows no signs of abuse, or "running it hard". just a thought

 

[JasonJ]

Re: Define "Pushing It Hard"

Running it hard is too much load, too high pitch of prop causing it to run too low of rpms, running too low of pitch which causes it to run too high or rpms, running it wide open all the time. Most will argue that running wide open all the time, with proper pitch prop, will not hurt a 2 stroke, and that is true. If a person runs like this the majority of the time, then going to 40:1 isn't a bad thing, or even going to a synthetic oil as well. Is the rpms you state wide open throttle? <br /><br />I'll put it to you another way. My 125 horse Merc is 35 years old, I run synth blend at 50:1, and wide open has me at about 6000 rpms. I can run like that for however long I want, and the engine does not mind it, but for the sake of economy I keep it down around 3800-4000 rpms. You always want to prop to get your rpms in the upper end of the wot range with moderate load, so it is never lugged if more load is in the boat. Too low of rpms will kill an engine more quickly than too high of rpms. Hope this helps a bit...

 

[Terry H]

Re: Define "Pushing It Hard"

Improper set-up would always be just that..."pushing it hard". That may be what you are referring to fatpratt...just a thought