Breaking in the engine question

[Kris_2020]

I just have a quick question about breaking in a Mercury 115 4-stroke. Dealer told me the time required to break in the new engines is shorter then it used to be.
According to the book I got it says for the first 2 hours run the engine at varied throttle speeds up to 4500 RPM and at full throttle for approx one minute every ten minutes.
Then for the next 8 hours you just can`t run at full throttle for more then 5 minutes at a time.

Dealer told me it is better not to run at full throttle for the first 2 hours and try to avoid doing it. If I must then only do it for about a minute.

So should I run full throttle os is it ok if I just avoid it for the first 2 hours? I don`t have to run at full throttle so that is not a problem but if it is better to do so then I will.

Also after the 2 hours can I run at say half the speed continuously for a long period or should I still vary my speed? And can I idle it then for longer or is that still bad?

[Hot Runr Guy]

Kris,
I'd follow the procedure in the owners manual. The dealers/mfgs can now download the usage history in the event of a problem, better to follow a written set of guidelines than what the dealer may or may not remember telling you to do.
As far as after the initial 2 hours, while they don't tell you NOT to idle for prolonged periods of time, it's probably not a bad idea to vary the rpm once in a while.
HRG

[turtle chain]

I also would follow the book but I wouldn't stay at one speed for long,And on my kicker the dealer said it is important to run full throttle for a good long while because most of there life is spent at slow speeds and the whole power band is not really used,My kicker runs like a watch now

[yarcraft91]

Plan on a day when you can run the boat for several hours and break it in by the book, including full throttle for 1 minute every 10 minutes in the first 2 hours. Don't be surprised if you find the motor wants to over- or under-rev at full throttle because it does not have the right prop. When I started breaking in my 50 EFI 4-stroke, the original prop (17 pitch) limited WOT rpm to 4500 (supposed to be 5500-6000), so I cut the day short until I could get a different prop (13 pitch)- no sense lugging or over-revving a new engine.

[turtle chain]

I also had the same problem my 1st boat,the dealer set it up with the wrong prop 1st thing out of the gate I over revved it .I don't understand a dealer who sells many of these boats sets it up with the wrong prop?? if we can guess what prop to put on better than they can ??Bottom line that motor ran great even with the over revving

[yarcraft91]

I also had the same problem my 1st boat,the dealer set it up with the wrong prop 1st thing out of the gate I over revved it .I don't understand a dealer who sells many of these boats sets it up with the wrong prop?? if we can guess what prop to put on better than they can ??Bottom line that motor ran great even with the over revving

Considering what's available on the internet, it's especially surprising. If my dealer's rigger had just checked the Mercury website prop selector, I'd have had the right prop in the beginning. But, my dealer sold more Evinrudes than Mercurys and that 17 pitch prop is right for a 'Rude with its higher lower unit gear ratio.

[Kris_2020]

So because I haven`t ran at full throttle at all when I`m out the next time should I wait 10 min again before I run full throttle or should I do it earlier?
Also how will I know if I have the right prop? If I get 6000 to 6400 RPM at full throttle does that mean I`m good?

[turtle chain]

I would bring up the throttle until you reach your max rpm limit and don't go any higher normally you will be lower than your rpm limit, If your Dealer knows anything,I guess I was really lucky on my new boat the owner took mine out and adjusted my jack plate and made sure I had the right prop.I brought her home and push play,much better than my first boat