How long should I run wide open

bowmanhere

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May 8, 2010
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5
[SIZE=4HI I have a 1969 johnson 4 hp 4w69b out and it runs great so far since i changed the fuel pump , this is what I need to know ,how long can I run it at top speed safely, and also how long can it run real slow? this is what I do now if I am just putsin around then I open it wide 4 a bit but 4 4 how long can I do that ? any feed back would be great Thanks
 

HighTrim

Supreme Mariner
Joined
Jun 21, 2007
Messages
10,486
Re: How long should I run wide open

When tuned properly, you can run it at either speed until the fuel runs out :)

Notice the disclaimer, "tuned properly"? That is water pump functioning as it should, ignition tuned, carb functioning as it should, etc...

That being said, I never run my outboards WOT for extended amounts of time, back off the throttle, and run at a cruise speed, saves on fuel.
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Re: How long should I run wide open

If the mtr is tuned properly and you are using the correct fuel/oil mix you can run it all day at WOT or Idle.
 

B-Dozer

Seaman
Joined
Jul 8, 2011
Messages
71
Re: How long should I run wide open

I had a 72 6hp evinrude i used for years as a teen and i would run that thing wide open for 3 hours at a time with like 3 guys in a 18ft flat bottom. Never had a problem with it on low idle or full speed !
 

Daviet

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Sep 24, 2008
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8,958
Re: How long should I run wide open

If the engine is propped correctly so that it will not over rev, you can run it at WOT as long as you want, your fuel useage will suffer.
 

bowmanhere

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May 8, 2010
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Re: How long should I run wide open

wanna say thanks 2 u all , Admiral what do u mean by over reving?
 

boobie

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Nov 5, 2009
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20,826
Re: How long should I run wide open

To keep it in the factory spec operating range for the mtr. You don't want to go above that.
 

Chinewalker

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Aug 19, 2001
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8,902
Re: How long should I run wide open

If the engine is propped correctly so that it will not over rev, you can run it at WOT as long as you want, your fuel useage will suffer.

Also, UNDER-revving can be just as bad. Lugging a motor is akin to driving uphill, in fifth gear, while towing a trailer - ping-ping-ping! As was noted, proper propping is very important. If this is a lightweight tinny, then the standard issue prop is likely okay. If it is an auxiliary motor, then a lower pitch prop might be called for.
 

Davem3

Chief Petty Officer
Joined
May 15, 2011
Messages
542
Re: How long should I run wide open

WOT= empty gas tank and clean and happy motor..............i run mine at WOT whenever possible to clean out the carbon
 

bowmanhere

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Joined
May 8, 2010
Messages
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Re: How long should I run wide open

Ok u guys I got it , thanks you all and tu 4 the help all good things 2 u all:)
 
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