Breaking in an outboard

Well i'm sure this is a subject that has come up a time or 20.Here is my question to anyone who has the knowledge that could help.
I have a marina that sells used and new outboards,they also specialize in rebuilds.I read my manual on my new 9.9hp 2stroke yamaha and it says idle only for the first ten minutes,then the rest of it as most people know with half throttle for a period,then 3/4throttle for a period etc.....
I talked to this guy at my marina who told me the most important time in an outboards life is the fist hr,whether it's a 2 or 4stroke.
He told me to disgard what the manual says and idle under load in f gear for a full hr as that is the most critical time.He said the fist hr of the lifes motor is to fully lubricate the motor from powerhead to the lower unit.He makes a good valid point by saying 10 minutes is not good enough to do so.I was just wondering if anyone has heard of this?To idle slow for the first hr instead of just 10minutes.He said after the first hr of idle then follow what the manual says,but make sure you idle for a full hr first.He said it will make or break the life and performance of the engine.

I'm trying to find out if there is any truth to this.I would really like to hear some opinions or if anyone has some good facts.Thanks

I would follow what the manual says. The engine manufacturers would all have engineers that specifically work on engine break ins so they would have done a multitude of tests in order to determine the proper break in cycles.

My dad just got a new ski boat that is an inboard/outboard and the manual has a 20 hour break in period....
The first 10 minutes was idle and then the next 2 hours was max 3/4 throttle and you weren't suppose to stay at a constant speed for more than 2 or 3 minutes. It will vary depending on the engine manufacturer. Follow the manual and you will totally be fine. If it didn't work, they would have changed the procedure by now.

The reason i'm asking is it just doen't make a whole lot of sense if you think about it.The manuf has you do 10 min of idleing and then you do hrs of each of the other specs like only 3000rpm for 2 hrs and then 4000 rpm for like 2hrs and then 3/4 for the rest of the time with full throttle every once in a while for no longer then 5 min at a time(this is just like an example i'm writing here)To me what will 10 min of idleing do for the motor that is my question?He just makes a heck of alot of sense.Plus if you go slow for an hr period it gives the premix a chance to really lubricate the powerhead as with 10 min it probally does nothing.Plus all the other stuff that needs to be worked in like the lower unit.I just don't think 10 min is enough,but that is why i want to see opinions here.

I can't see how an hr of idle time will not help the motor more then a 10 min idle time.The motor barely even gets warmed up after 10min.Plus this guy who owns a marina has broke in every outboard the same way and has had great success with it.He has been rebuilding motors for 30yrs.He told me that an hr of idleing will help seat the rings perfect and break in the pistons properly,plus all the gears and everything else that gets broken in will be as good as you can get this way.

Also it says to run the motor at a 100:1 oil ratio that very few people do,most people run it at 50:1.

Well i hope more people an shed more light on this.

ILOVTOFISH said:

Also it says to run the motor at a 100:1 oil ratio that very few people do,most people run it at 50:1.

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Is it an oil injection model? I have never owned a Yamaha, but most/all? my two strokes recommended running about double the normal oil during the first tank of gas for break-in. Oil injection models usually require an oil mix for the 1st tank.

As stated above, I'd normaly would go with what the mfg says. Contact Yamaha to make sure you have the latest recommended procedure.

ILOVTOFISH said:

The reason i'm asking is it just doen't make a whole lot of sense if you think about it.The manuf has you do 10 min of idleing and then you do hrs of each of the other specs like only 3000rpm for 2 hrs and then 4000 rpm for like 2hrs and then 3/4 for the rest of the time with full throttle every once in a while for no longer then 5 min at a time(this is just like an example i'm writing here)To me what will 10 min of idleing do for the motor that is my question?He just makes a heck of alot of sense.Plus if you go slow for an hr period it gives the premix a chance to really lubricate the powerhead as with 10 min it probally does nothing.Plus all the other stuff that needs to be worked in like the lower unit.I just don't think 10 min is enough,but that is why i want to see opinions here.

I can't see how an hr of idle time will not help the motor more then a 10 min idle time.The motor barely even gets warmed up after 10min.Plus this guy who owns a marina has broke in every outboard the same way and has had great success with it.He has been rebuilding motors for 30yrs.He told me that an hr of idleing will help seat the rings perfect and break in the pistons properly,plus all the gears and everything else that gets broken in will be as good as you can get this way.

Also it says to run the motor at a 100:1 oil ratio that very few people do,most people run it at 50:1.

Well i hope more people an shed more light on this.

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The most important break-in time you can put on an engine is the first block of idle time!! Along with the fact that the engine should have additional oil in the fuel the first few minutes of run time is where the majority of metal is coming off the cylinder walls as the rings are taking the high points off of the honing process in the steel sleeves. The additional oil and fuel at idle should help carry away this debris rather than have it lodge in the aluminum piston skirt which will promote a higher rate of wear during the life cycle of the engine. Also, as far as being "barely warmed up" goes the thermostat on that engine works mainly at idle and the engine block will or should be at it's warmest at idle. Am finishing up a V4 at work later today that will have a couple hours of double oil idle time before it ever sees advanced throttle settings. Would also run 50:1 in your engine for the entire life cydle of it.

So pappy what your saying is this guy is right.I have only started the motor once in my yard.It has never seen water yet that is why i'm asking this.I am running a 25:1 oil ratio as of now.I figured a full 3 gallon tank full of double oil would be about right.So what your saying pappy is i should go more then an hr of idle time in f gear or an hr on a small motor like this is plenty.If i need to do 2hrs please let me know.The book says 10min which doesn't seem like enough time to me.

Also like i said the book also says 100:1 oil ratio after 10hrs of being broken in and most run a 50:1 ratio.
I want this motor to last as long as possible.So pappy please let me know if you can on how long i should idle the motor for before going to the next step of opening the throttle up,thanks.

I'd follow the manual like that other post said. They printed it for a reason. I'm no expert on outboards but I have worked in a car factory for over 20 years and if they are anything like the motors in cars then it has been run quite a bit already. I would think that they start and run them at the factory to check for leaks and to make sure it runs. (they do cars anyway)

My guess is the 10 mins they mention is to get it up to temperature.

Well i know for a fact as you mention the testing of outboards that is what happens.I think all motors must pass a series of tests before they ship them out.Also mentioned in the manual is run the outboard at a 100:1 oil ratio after a 25:1 breakin.I don't know of many people who do that as most run it at 50:1.When i bought it at the marina all the mechanics even said run it at a 50:1 oil ratio and ignore the manual if i want my motor to last.

I think the manual is more of a guiding tool then anything else.I will do as the guy said at my marina and what pappy said,run it for at least an hr or 2 in f idle.That just makes the most sense to me.I just can't see how everything can mesh as far as gears and all the other stuff in just 10 min.I think as pappy mentioned it takes some time for all the gears and whatever else needs to be worked in.I will do at least an hr at min to work the motor in.Then after that folllow close as possible to what the manual says.The guy at the marina i bought my yamaha said he usually broke in his outboards in half the time the manual says (5hrs)and has never had a problem ever.

He said after the first hr or 2 he would just not do much if at all wide open throttle.He would vary all the speeds up to about 3/4 throttle with 1 or maybe 2 times total of wide open throttle for a minute or 2 a piece and that was it.So basically an hr or 2 of idle and then 3hrs of going through the whole rpm range up to 3/4 throttle and after 5hrs do as you please.I will do the full 10hrs as the book stated with the only difference being idleing for longer then 10min.I'm in no rush so i may as well do it correct.

Thanks for all the posts so far they have been helpful.

The manuals are written by a joint effort of Engineering, customer service, and technical writers but you better believe that before it hits the pavement it has to pass through the dreaded Marketing Dept. Those are the guys that would be saying the "Numbers" would suffer if the engines have to have an elongated break-in time. They have more clout than you would believe!
If it were me I would enjoy an hour or more at idle with the mixture you already have and then go through the rest of the process. As I said earlier the engine block will be at it's warmest at idle and the pistons will not be at their designed maximum dimentions due to the low load on them. You will have the maximum piston to wall clearances at idle. That is the absolute best time to get rid of the initial cylinder wall debris generated by break-in so let the enriched mixture wash it away.

FWIW:
I looked at the Yamaha 2-stroke break-in procedure. That 1st 10 minutes, which recommends "fast" idle and not in gear. I am not an outboard engineer, but that sounds like just getting the motor up to operating temp. The yamaha procedure matches my nissan's break-in procedures.

I also looked at my new to me Merc 25 2 stroke manual, and the break-in is significantly different. It says 1 hour break-in, and to avoid remaining at contstant speed for more than 2 minutes and sustained wide open runs. That's it.

All recommend 25:1 during break-in.

I have never seen one that calls for 1 hour of idling.

The manual is written by the people who know the engine best. Just follow what the manual says.

Good stuff guys but i will listen to pappy as he knows motors inside and out.Plus the marina i went to told me this before pappy agreed with it so there must be something more to it then we think.

Like i said it just makes more sense to idle in gear for over an hr to mesh everything.
Also with the manual,i belive once again it's a guide tool not the exact way to do things as most people i know don't even break there motors in,for what reason i don't know.Probally lack of patience.

If everyone followed the manual they would run a 100:1 oil ratio,most people don't so that goes against the manual or what the engineers say.Most people think it's a marketing thing for cleaner air (epa).I don't know many people who run yamaha motors at 100:1.I'm sure there is a few but most go with the 50:1.

Plus usually you run double oil in your 2stroke on breakin.
Why does yamaha say to run a 25:1 breakin on the oil and then 100:1.After that it should be 50:1,instead it's 3 times the oil at breakin instead of double.Thats odd.I have heard so many different theorys of breaking in a motor,but the idleing for at least an hr makes the most sense to me.

Well that article is quite interesting.I have a 2stroke motor though.Plus it doesn't mention boat motors once.Maybe a few other people will read that article,lets see what they think.Pretty good stuff though.Also i forgot to mention the guy at my marina said that about 4strokes,to idle for a bit and then just go hard after that and ignore the 10hr brekin procedure.The reason i didn't write this to begin with is i have a 2stroke outboard so i don't know if the pistons and rings are the same type as the newer 4strokes.

4stroke motors in cars and boats are built on the same concept.We rarely ever breakin a car when we drive it for the first time so why would a 4stroke outboard be any different.That makes a ton of sense what he says in the article to go hard from the get go as we do in cars.No one ever gets their car and idles for an hr,then goes through the rpms for 10hrs so i belive he is right on the 4stroke motors 100%.Well hopefully some people will chime in on this plus the article.

ILOVTOFISH said:

Like i said it just makes more sense to idle in gear for over an hr to mesh everything.

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Why? Because you feel the lighter load is better and softer on the engine? Most metal to metal contact surfaces need a load and friction to mesh. Have you seen any flat based lifter cam break-in recommend idling? Why is synthetic generally not recommended for break-in?

You sound like you are being extra cautious with your 1st new outboard. For the cost and time of a phone call to the mfg wouldn't you want their confirmation?

The 100:1 discussion is seperate and not justification for not following the break-in.

In the end, idling for the 1st hour "may" be more detrimental than someone that just "runs" their engine without paying attention to the break-in procedure.

PS: I had a MUCH longer post which was lost on update (got logged out!) :x

ILOVTOFISH said:

Well that article is quite interesting.I have a 2stroke motor though.Plus it doesn't mention boat motors once.Maybe a few other people will read that article,lets see what they think.Pretty good stuff though.Also i forgot to mention the guy at my marina said that about 4strokes,to idle for a bit and then just go hard after that and ignore the 10hr brekin procedure.The reason i didn't write this to begin with is i have a 2stroke outboard so i don't know if the pistons and rings are the same type as the newer 4strokes.

4stroke motors in cars and boats are built on the same concept.We rarely ever breakin a car when we drive it for the first time so why would a 4stroke outboard be any different.That makes a ton of sense what he says in the article to go hard from the get go as we do in cars.No one ever gets their car and idles for an hr,then goes through the rpms for 10hrs so i belive he is right on the 4stroke motors 100%.Well hopefully some people will chime in on this plus the article.

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I think you need to be asking yourself, what wouldn't apply to modern 2-strokes as far as rings, surfaces, materials, crosshatch, etc? They are not the same, but they are more similiar than dis-similiar.

BTW, I am not advocating the mentioned article of doing very heavy load break-in, but it might provide you with a clue to why you would not want to break-in with such a light load of idling.

You know fuzzy grub i think you may be right.I just did a ton or research and it seems like it's a 50/50 subject.There is a couple of forums i just went on were people said they called merc which i know it not yamaha but same kind of motor (2stroke)and asked them if they should break it in by the book.The biggest kicker was they said they have a ton more problems with outboards that are babied in the breakin procedure.

Basically balls to the walls is what alot of people are doing lately and they seem to have good luck.The article that was mentioned (mototuneusa)seems to be used by a ton of people with great results according to the 100 or more sites i just went on.Some guy used his method on over 5 different outboards with great results.Maybe that is why evinrude etec uses it.They go balls out from the start.I know the computer is programmed to put out a ton of oil at breakin but what makes that any different then a yamaha or merc 2stroke if your using double oil as they do?

The thing is as mentioned in all breakin procedure articles is you only have one chance to do this right,i don't want to mess this up.That is whay i want to make sure whichever way i go is the proper way.I think everyone here so far has put some great input in.I like what pappy said and i like what some other people said here.The problem is which is the absoulute right way.I have heard in the past from merc dealers that have been in business just go hard out of the box,but i have also go by the book.Only one way is correct.Also with the manual who knows how long it's been since it's been really looked at and updated as it may be printed from oldschool,i would guess things have changed from then.

I have a 2004 merc 15hp 2stroke manual and it says break in that motor for only one hr with double oil but it doesn't mention any certain rpms,it just states run the double oil and then after an hr go to normal oil ratio of 50:1 with reg operation.I can't see the yamaha being any different.

Well now i just called a yamaha rep for the heck of it.Of course he said follow the breakin period,but he also said as a rule of thumb you usually want to break in the motor the same way you plan on using it full time.So in one sense he said doing it balls out won't hurt it.Also he said if the motor is going to have any problems it would be usually happen right away.The way he breaks in his outboards is by the way he runs them all the time he said.

The most important thing he said was make sure you always warm the motor up before going full bore with it.The most important thing also for break in was the double oil of course,he also said you can run it at a 100:1 if you want but i would stick to at least a 75 or even 50:1 if i do alot of wot.That is very helpful.I asked him about idleing for a long period of time before opening it up and his response was that is a no,no.So there is so many conflicting arguements about this subject maybe there is no wrong or right way to do it.Well if anyone wants to add their knowledge to this please feel free.

Just take it easy for the first little whille...like first hours then let it all out.For example when we buy new vehicles (VW,Nissan,BMW,Honda...i once owned an Oldsmobile Omega...an 1982 ...) i allways darin out the brake in oil as soon i get them home... and fill them with synthetic engine oil and never had a problem....never .
Dan :idea: