Wide open throttle (WOT) Merc 40 EFI ?

Expidia

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I've already gone past the 8 hour break in period. Up to that point the manual says don't run at the same speed too long or something to that effect.

So I'm past the break in now and my question is whenever I let my Son drive the boat he likes to run WOT almost all the time he's driving it. Of course when conditions allow (he's not blowing by other boats or anything like that.

The rig has a top speed of 32 mph up from 22 mph now that I've upgraded from a 30 hp.

So it's not like he's doing 60 mph all the time, it's just that when I'm driving I give up a few mph's, so I run at 3/4 throttle most of the time.

So my question is . . . can damage be done to a 2007 40 HP mercury EFI if it's run mostly wide open for 30 minutes or so at a time?
 

Frank Acampora

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Re: Wide open throttle (WOT) Merc 40 EFI ?

Don't know about the 2007 but I do know that young boys only know one throttle setting. Slow is not a word in their vocabulary. My son was the same way. No matter what you say, he is going to drive it the same way. I let my son drive me to Baltimore once--ONCE-- in a 15 footer. He had the damn boat in the air quite a bit and when I got home, I actually had a bruised butt.
 

tashasdaddy

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Re: Wide open throttle (WOT) Merc 40 EFI ?

they are built to run wide open. let him buy the gas, and he will learn that taking the motor to WOT, then throttling back to 7/8 throttle saves gas, as the carbs close a little but the timing remains the same.
 

Expidia

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Re: Wide open throttle (WOT) Merc 40 EFI ?

Don't know about the 2007 but I do know that young boys only know one throttle setting. Slow is not a word in their vocabulary. My son was the same way. No matter what you say, he is going to drive it the same way. I let my son drive me to Baltimore once--ONCE-- in a 15 footer. He had the damn boat in the air quite a bit and when I got home, I actually had a bruised butt.


He's pretty good on slowing down for the wakes, but he drives the boat like it's a "Go Cart".

He has only two speeds . . . Stop and WOT!
 

Expidia

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Re: Wide open throttle (WOT) Merc 40 EFI ?

they are built to run wide open. let him buy the gas, and he will learn that taking the motor to WOT, then throttling back to 7/8 throttle saves gas, as the carbs close a little but the timing remains the same.

Ya, I thought about charging him for the gas . . . but it's only a 6.5 gal tank so he can't go through more than about $20 bucks anyway or he'll be learning how to propel the boat with the one paddle I have onboard.

I think I'll limit him to RPM's on the tach and just tell him I don't want to run "my" motor over 5,000 rpm's for extended periods.

But your answer is what I wanted to hear in that they are "built to run wide open". That makes me feel a little better that extended WOT won't blow the motor up.

I heard a guy how works at the dealership telling another buyer when the guy asked him about the break in period on his new outboard that it's OK to run the p*ss out it, he said these motors like that!

But when I overheard that I just figured he's in the business of selling the same people new motors every few years after they burn them out.

The operations manual was totally opposite of how he was telling the guy to break it in.
 

deejaycee_2000

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Mar 28, 2006
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Re: Wide open throttle (WOT) Merc 40 EFI ?

just set the throttle stop screw a little .... then he thinks he is going WOT but actually not ....
 

deejaycee_2000

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Re: Wide open throttle (WOT) Merc 40 EFI ?

right .... then let him buy his own motor ......
 
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