YACT: Proper break-in... floor that sucker...

[boyRacer]

Link

Ok this guy claims that it's better to push the engine hard than follow the instruction manual... ... be it bikes or cars... i dunno...

 

[geno]

You need to make some full throttle runs to seat the rings right. He's right about that. But about redlining the motor right after the rebuild, I'm not so sure about that one...

 

[Antisocial Virge]

Whenever I did a rebuild I always did several 20-60mph runs to set the piston rings. Thats basically the same thing he is saying there.

 

[Confused]

One of my friends was driving down the motorway, saw this brand new Merc doing about 100 past him. Had just passed the car, and BANG!!!! Huge loud noise, huge puffs of steam and smoke rising from the front end of the Merc.


The Merc driver had blown the piston (or had done somthing to it), and the large bang was the head, and piston, smashing into the under side of the bonnet.


I will always follow the manual when I get a new car!



Confused

 

[boyRacer]

So how long are you supposed to run the engine hard...? The site says 20 miles... so how are you supposed to drive it or ride it after that period?

 

[T2T III]

Originally posted by: Confused
One of my friends was driving down the motorway, saw this brand new Merc doing about 100 past him. Had just passed the car, and BANG!!!! Huge loud noise, huge puffs of steam and smoke rising from the front end of the Merc.


The Merc driver had blown the piston (or had done somthing to it), and the large bang was the head, and piston, smashing into the under side of the bonnet.


I will always follow the manual when I get a new car!

Confused

Was that Ornery in the Mercury? :Q

 

[Zenmervolt]

He's mistaken about the owner's manual recommendations. Every manual I've seen says to avoid heavily loading the engine, making WOT runs and maintaining a constant speed. Most do recommend 3/4 throttle runs (though not to redline) with the car in the proper gear. The main thing is to avoid "lugging" the engine and to avoid constant-speed cruising.

ZV

 

[notfred]

Originally posted by: Confused
One of my friends was driving down the motorway, saw this brand new Merc doing about 100 past him. Had just passed the car, and BANG!!!! Huge loud noise, huge puffs of steam and smoke rising from the front end of the Merc.

The Merc driver had blown the piston (or had done somthing to it), and the large bang was the head, and piston, smashing into the under side of the bonnet.

I will always follow the manual when I get a new car!

Confused

I find it hard to belive that he blew the cylinder head completely off the car. If he did, it was a defective engine and they forgot to put head bolts in it or something.

 

[b0mbrman]

If you want it to last longer, be gentle. If you want it to push harder, be rough.

 

[Eli]

I do not agree with this guy at all.

I would never treat a brand new engine that way.

What he says makes sense, but I think he is taking it too far... I don't think it really works like that in real life. There should be plenty of pressure behind the rings to seal them, even at idle.....

I break all my engines in at an idle to 2/3rds throttle. Never more.

Another thing that makes me think he's full of crap are his comments about synthetic oil preventing break-in, which is absolutely not true.

He makes it seem like he knows what he's talking about..... but I question it, heavily.

I don't know. I suppose it's possible.... I don't think I'm going to be trying it anytime soon though.

Man, I want to become an Internal Combustion Engine Researcher.. If I had the money, I would run some tests myself... I do find the theory interesting, I just question its real-world validity.

That picture of the Honda F3 pistons is a joke. There is no way that clean piston came fresh out of an engine. Give me a break. That thing looks like it's been polished with a buffer.

 

[The Stigenator]

MotoMan! I wondered where he went after he left MCUSA.

I trust him for some of the things. The guy is knowledgeable.. he has rebuilt so many freaking machines the guy is god when it comes to setting up bikes to race and stuff.

 

[Eli]

When I broke my Honda GXH50 in, I let it idle for some 10 hours.

I changed the oil every 3 hours, and gave it a rev here and there. I wanted to make sure it was very well broken in before I gave it any load.

When I eventually have to open the engine, I will see if there was lots of blowby and piston scuffing. According to this guy, what I did was the worst thing I could do... Nonsense I say.

The rough crosshatch pattern in the cylinder bore acts like a file to allow the rings to wear. The rings quickly "use up" the roughness, regardless of how hard the engine is run.

If the rings aren't forced against the walls, they'll use up the roughness before they fully seat. Once that happens there is no solution but to re hone the cylinders, install new rings and start over again.

Uh......... Once the crosshatch pattern is gone, the rings are seated. It's not like the rings don't rotate themselves. They're in constant revolution because of the side forces the piston sees.

At least he recomends to warm the engine up completely first....

Synthetic oil is so slippery that it actually "arrests" the ring sealing process before it's complete.

This is a myth that has been propagated by God knows who for a number of years. However, you shouldn't use synthetic to break in.. Not because it will prevent breakin, but because there is no point in spending extra money on higher quality oil when you are just going to change it soon anyway.

Actually, the operation of plain bearings doesn't involve metal to metal contact !! The shiny spots on used
bearings are caused from their contact with the crankshaft journals during start up after the engine has been sitting a while,
and the excess oil has drained off. This is the main reason for not revving up the engine when it's started.

Nonsense. No machining, nomatter how accurate, is perfect on a microscopic level. Breakin "remachines" every friction surface in the engine to fit together.

Q: What about the oil filter, doesn't it catch the metal paste ??

A: When soft metals are loose in the engine, they get pulverized by the gears and oil pump,
and the super fine particles do get past the entire filtration system. These particles are too small to "scratch"
the bearings, but they do something much worse ... they coat them, and take up the oil clearance !!

I have a major problem with this statement, because it is absolutely incorrect. Yeah.. an aluminum paste isn't going to "scratch" a bearing, it's going to polish it! Think about it. When you polish something, you use an extremely fine buffing compound.. It's not course enough to scratch, but it is still removing metal! Deep gouges are just as detrimental to an engine as extreme clearances.

Ugh. I feel the need to fire an email off to this guy and tell him to explain himself.

 

[Eli]

bump because the superbowl took the focus away from the normally busy car threads.

 

[ElFenix]

Originally posted by: Eli

He makes it seem like he knows what he's talking about..... but I question it, heavily.

everyone on the internet seems to know what they're talking about

 

[Eli]

Originally posted by: ElFenix

Originally posted by: Eli

He makes it seem like he knows what he's talking about..... but I question it, heavily.

everyone on the internet seems to know what they're talking about

I don't claim the guy is an idiot when it comes to engines, but I think he's gotten a theory stuck in his head and he's way overanalyzed it.

 

[boyRacer]

ok so consensus is... run it harder than normal... but not to redline. good enough for me since most people usually break in cars by going long driving...

 

[Eli]

I fired an email off to him, we'll see what he says.

Bah, break your engine in any way you want to.. Just change the oil. And for god's sake, let your engine warm up before you floor it.. even if it has 100,000 miles on it.

 

[boyRacer]

Originally posted by: Eli
I fired an email off to him, we'll see what he says.

Bah, break your engine in any way you want to.. Just change the oil. And for god's sake, let your engine warm up before you floor it.. even if it has 100,000 miles on it.

LOL... actually i think i'll do little full throttle runs... but never redlining. Oh... and i do warm up the engine... i'm one of those car freaks that feel sympathetic towards cars...

 

[C'DaleRider]

Originally posted by: ElFenix

Originally posted by: Eli

He makes it seem like he knows what he's talking about..... but I question it, heavily.

everyone on the internet seems to know what they're talking about

What I always question is how the manufacturer of, in this case an engine and car, is so unknowledgeable about the specific product they produce. Like this case.........the mfgr. recommends a break-in period and such, and yet "the experts on the internet" know better than the company that designed and built it in the first place. Yes, the mfgrs. do err on the side of longevity and durability, but to say essentially the mfgrs. don't "understand" or know how to break-in a new engine is silly at best.

And about the synthetic oils.........strange how GM puts Mobile1 into the 'Vette as its first fill at the factory, MB puts it in their entire fleet of autos as a first fill at the factory, and I don't honestly think those engines have any difficulty getting broken in. Old wives' tale.

 

[CraigRT]

Originally posted by: Confused
One of my friends was driving down the motorway, saw this brand new Merc doing about 100 past him. Had just passed the car, and BANG!!!! Huge loud noise, huge puffs of steam and smoke rising from the front end of the Merc.


The Merc driver had blown the piston (or had done somthing to it), and the large bang was the head, and piston, smashing into the under side of the bonnet.


I will always follow the manual when I get a new car!



Confused

That's Merc though.. blah.

my dads Maxima.. 413km on the odo (2nd day old) and going 100 down the highway. put the gas down and didn't stop 'til 215.
now THAT's break in.
that was 3 years ago.. has the car had a problem? no. does it burn oil? no... broken in RIGHT

 

[Hamburgerpimp]

Break in a new car any way you want. Fvck it, you got the warranty. As for synthetics and my new Tacoma, they advise not to use Synthetic before 15K. And the dealership says that!

 

[Eli]

I want to discuss this more.

 

[spidey07]

Anybody want to comment that is actually a mechanic for a living?

I've alway "heard" from many mechanics that you do want to run through the gears during the first 1000 miles without changing the oil (something like there are special additives in the motor when new). Even some redlining. Move that needle around some! Don't drive at a constant speed or tow. After 1000 miles though in the oil and filter of your choice.

The end result is supposed to be a smoother, faster motor with fewer problems.

So this is what I "heard" from three mechanics in three separate shops that have been competitively racing a combined 60 years. Take it for what it is.

 

[Eli]

Originally posted by: spidey07
Anybody want to comment that is actually a mechanic for a living?

I've alway "heard" from many mechanics that you do want to run through the gears during the first 1000 miles without changing the oil (something like there are special additives in the motor when new). Even some redlining. Move that needle around some! Don't drive at a constant speed or tow. After 1000 miles though in the oil and filter of your choice.

The end result is supposed to be a smoother, faster motor with fewer problems.

So this is what I "heard" from three mechanics in three separate shops that have been competitively racing a combined 60 years. Take it for what it is.

lol, there are no "special additives" added to an engine when it's brand new...

 

[spidey07]

eli,

Notice the disclaimers of what I heard and what not. I'm not stating anything as fact, simply heresay.

But I would like somebody who is qualified with experience to set me straight or comment on my post.

lol, there are no "special additives" added to an engine when it's brand new...

Nothing? Just run of the mill motor oil? No other lubicants at all on the top or bottom end parts? Valve bushings?