What is appropriate break-in? REALLY???

[scooper77515]

Book says first tank of fuel with 1/2 gallon of injection oil, and 10 hours of 75% throttle, but then adds

During this period, maximum throttle
should not exceed 3/4, however, brief
full acceleration and speed variations
contribute to a good break-in. Continued
wide open throttle accelerations,
prolonged cruising speeds and overloading
the engine(s) are detrimental
during the break-in period.

So, what is "brief full accelleration"? Can I use it to pull up a skier with a brief full accel until planed then back of to half throttle, or should I wait until after break-in for skiing?

Should I stay at 3/4 for most of the time, or vary between half and 3/4, with 2-5 minute full throttle hits? Or is that too long?

Any feedback and experience would be appreciated.:cheers:

 

[sporsterjoel]

I would wait till after... brief would be full throttle till you hit top speed then let off right away, and i would move the throttle back and forth every couple mins. just dont exeed 3/4 though, except for the ODD full throttle.

 

[scooper77515]

So do everything gently, no hard takeoffs or quick changes in speed?

Full speed for what amount of time max? Are we talking just a few seconds, or a minute or 2?

Hate to sound whiny, but I want to do it right and really don't want to do this again any time soon :ack:

 

[Nate Surveyor]

OK, just send it to me, I'll break it in, and email it back to you!



Nate

 

[sporsterjoel]

So do everything gently, no hard takeoffs or quick changes in speed?

Full speed for what amount of time max? Are we talking just a few seconds, or a minute or 2?

Hate to sound whiny, but I want to do it right and really don't want to do this again any time soon :ack:

yup but i would keep the full speed to 1-2sec. dont be scared of it, main point in a breakin is 1) dont drive it hard and 2) dont drive it at one rpm level 3) let's all the parts in the motor a chance toget to know each other befor you start beating on it...

 

[scooper77515]

OK, thanks. The 1-2 seconds part is what I really needed to know, otherwise I would have been doing several 2-4 minute full throttle bursts.

Nate, I tried to send it to you as an attachment, but it kept saying it was too big...:rofl:

 

[Gunsrunner]

Have a read of this scooper, i thought a lot of what he writes makes sense!!:agree:
http://www.mototuneusa.com/break_in_secrets.htm

 

[timmyboy76]

Scoop..may be wrong/theory aint quite correct, but using "injector oil" to premix gas, to me, wouldn't cut it. Injector oil, would not mix right, and just settle to bottom of fuel tank, yah, would mix some, but not like "premix oil", where that stuff mixes thoroughly. Makes me think why, theres 2-types of labeled oils...Injector only and Premix only oils...my .02???

 

[scooper77515]

I wasn't aware that there were a difference.

I had the synthetic by the gallon, so I added half a gallon to it.

Gunsrunner, he specifically states that this break-in procedure is for 4-stroke engines. And newer technology in engine building. I have a 10 year old engine that has never been run, so I am assuming this is "older" technology (relatively) and of course, mine is a 2-stroke.

I have used similar break-ins to what he is describing in my vehicles...

 

[unclejay]

Stop

First of all, the advice on that web site is right on. Been using that technique for 40 plus years and two Speedsters.

Second, never use synthetic oil during break in, it will prevent the rings from seating because it prevents the normal wear which seats the rings.

Next, use only Sea Doo oil, not outboard motor injection oil, positively... both in the gasoline and in the oil tank. The idea is just to increase the oil/fuel ratio for the first 10 hours or so.

Never mix oil types during break in. After break in, some mixing is OK but not a good practice.

Short bursts of wide open throttle is OK but not under full load like pulling boarder out of water. The idea of full throttle is to get the piston to 'scrub' the very top of its stroke (due to con rod stretch at high rpm).