Why I support Nissan's break in period period

InnerDragon10

Yes, another thread about the break in period. HOWEVER, I hope to shed an educated light on the debate. I work as a reliability engineer. A what? An engineer concerned with prolonging equipment life for an industrial plant. I've had training/certification in lubrication analysis, vibration analysis, infrared, bearings maintenance, electric motors, etc.

Nissan recommends the following:
During the first 1,200 miles follow these recommendations to obtain maximum engine performance and ensure the future reliability and economy of your new vehicle.

Avoid driving for long periods at constant speed, either fast or slow.
Do not run the engine over 4,000 rpm.
Do not accelerate at full throttle in any gear.
Avoid quick starts.
Avoid hard braking as much as possible

I agree with Nissan's 'slow and steady' break in period. Here's why. When breaking in an engine, it is really not likely that internal machine tolerances are THAT out of wack; Nissan has probably gotten pretty good at machined parts and fitment. If there are any slightly off spec tolerances, you would want them to wear in gently and evenly. A gentle break in period allows for this. If you run the engine like you stole it, you risk inducing stress concentrations in machined parts and microscopic fatigue/cracking in the metal. This fatigue will NOT be noticeable for quite some time. But give it thousands of miles and a couple years, and those cracks propogate; fatigued metal begins to spall (tiny chunks break off). Other engine parts need to wear themselves in as well, such as bearings. Again, there should be no unreasonable machine tolerances in a new engine. But machining processes are not perfect, so tiny imperfections may exist, and a gentle break in period allows components to wear in in a 'safer' manner.

"If you don't run it hard, you won't seat your rings and you'll lose power"
Honestly, I do not know about specific engine parts, nor have I worked on them. But I find it hard to believe that one must run an engine hard to get the (piston?) rings to seat properly.

"Gentle break in promotes carbon buildup! It'll kill your engine"
I HIGHLY doubt that a new engine will have ANY carbon deposits after 1,200 miles. If it does, we're talking about MINUTE amounts that will dissipate from spirited driving after the break in period. Unless you're just using absolute crap for gasoline (and I mean ABSOLUTE crap). Not to mention carbon deposits occur over time and are largely influenced by the maintenance you perform on your engine over its life.


Just my two cents Hope it's informative to some.

Chuck33079

Now we sit back and wait until someone posts that old mototune article about breaking in motorcycle engines that says to beat the hell out of them early and often.

__________________
2011 MB Touring-Sport-6sp-Nav/GTM TT/FI TT TDX/JTran/Kosmic/Eibach/Hotchkis/SPC/CSF/RPS/SoThatsWhereAllMyMoneyWent

osbornsm

Inb4

__________________

Chuck33079

It's funny how engineers always support the breakin period, and guys who read stuff on the internet will tell you that breakin periods don't matter.

__________________
2011 MB Touring-Sport-6sp-Nav/GTM TT/FI TT TDX/JTran/Kosmic/Eibach/Hotchkis/SPC/CSF/RPS/SoThatsWhereAllMyMoneyWent

enkei2k

Break In Secrets--How To Break In New Motorcycle and Car Engines For More Power

?

__________________
...need boost...

Chuck33079

Yep. Doesn't everyone usually get all of their info from badly designed websites from the early 2000s rather than the engineers who designed the vehicle?

__________________
2011 MB Touring-Sport-6sp-Nav/GTM TT/FI TT TDX/JTran/Kosmic/Eibach/Hotchkis/SPC/CSF/RPS/SoThatsWhereAllMyMoneyWent

InnerDragon10

Interesting - I did not know about the crosshatch pattern on cylinder bores to profile the piston rings. I noticed the website mentions that the first 20 miles are most critical to overall engine life. I picked my car up with 24 miles so... guess it doesn't matter?! In addition, I have a problem directly comparing motorcycle engines to car engines. Yes, they're the same concept.. but can one honestly assume that what's good for a bike is good for a car? 14,000-16,000RPM redline vs. 7500RPM redline? Different weights of the mechanical components, different pressures, etc. The website does offer compelling evidence though. The debate lives on... I'm sticking to my guns though

EDIT:
Something else I just thought about. Here in the industrial plants we have high speed gearboxes all over the place for equipment. Any of you that have replaced transmission/differential oil have probably wiped off the metal shavings that collect on%

Chuck33079

That article is highly questionable as far as I'm concerned. I just posted it to head off the people who believe it. To confuse the issue more, who still changes the oil after the breakin period? I always do. The metal from the breakin process has to go somewhere, right? But I don't see this recommended anymore.

__________________
2011 MB Touring-Sport-6sp-Nav/GTM TT/FI TT TDX/JTran/Kosmic/Eibach/Hotchkis/SPC/CSF/RPS/SoThatsWhereAllMyMoneyWent

RoyaltyB

Just out of curiosity, and since I don't have my manual with me, does the manual specify a break in period? Is it part of the dealer checklist when selling the car? (not that the dealers know jack crap about our cars)

__________________
Fast Intentions Stage 1 TT / F.I. 2.5 CF CBE / SpecialtyZ Max Street Clutch / F.I. 34 ROW OIL COOLER / VALENTINE ONE W/BLENDMOUNT / LAKERS LICENSE PLATE FRAME (GOTTA REP THE PURPLE AND GOLD )

ZMan8

I support the recommended break in

Sent from my SAMSUNG-SGH-I747 using Tapatalk

__________________
2010 370Z 40 Anniv., 6 MT | Fast Intentions | Swift Springs | SPC | Z1Motorsports | JWM | Redline Oils | 35% Window Tint
2015 Mazda6 | 370ZChicago: Chicago Area Cars & Coffee

Chuck33079

1200 miles per the manual.

__________________
2011 MB Touring-Sport-6sp-Nav/GTM TT/FI TT TDX/JTran/Kosmic/Eibach/Hotchkis/SPC/CSF/RPS/SoThatsWhereAllMyMoneyWent

Infidel

I read somewhere that the GTR motors are run wide open for an extended period of time before install, does anyone have a link that supports this?

ZMan8

I hear a similar thing for all corvette engines.

__________________
2010 370Z 40 Anniv., 6 MT | Fast Intentions | Swift Springs | SPC | Z1Motorsports | JWM | Redline Oils | 35% Window Tint
2015 Mazda6 | 370ZChicago: Chicago Area Cars & Coffee

FrostyNaples

Back in 2003, when I purchased new a Sentra SE-R, I broke it in leaving the dealer lot , bouncing off the rev limiter going down the street.

6 years and 103,000 miles later, I traded it, in perfect running condition.

I'd be more inclined to believe the 'break in period' with first hand experience and not what others say.

Now with the Z, i've given it more of a gentle approach, but I chalk that up to age...

__________________
2013 Pearl White (Base) 7A - DD

Jordo!

My understanding was also to allow for lots of coast down during break-in to induce extra vacuum and seat the rings better.

Other than that, your break-in rationale makes sense, and is one I have always followed with any new motor.

__________________
Enjoy it. Destroy it.