Some automakers like I think the Honda Civics got flogged and hotroded off the assembly line on a road test. I personally think a production style engine does need a hard or soft break in. Just normal to brisk driving at varied speeds seems to work fine.
Breaking In A New Or Rebuilt Engine Hard Or Not ?
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Originally Posted By: mechtech2
Originally Posted By: Scott_Tucker
I just bought a brand new Civic Si today and it will be broken in hard. Those who *really* know how an engine works know there is a scientific reason to do this.
Oh, Puleeze!
Maybe you can sell your idea to the car Mfrs, who don't abide by this, nor do they recommend it for the new car purchasers.
Why? There is no need, just a bit slower break in.
Engines have already been dyno run, oft pretty hard before fitment (Chevy did it on Natural Gas in the 50s)
Clutches, gearboxes, diffs etc. all like a chance to get to know each other, but the acceleration/over-run techniques at half throttle and 2/3 revs should help this also.
80MPH on a new tranny and diff isn't probably the best.
Originally Posted By: Scott_Tucker
I just bought a brand new Civic Si today and it will be broken in hard. Those who *really* know how an engine works know there is a scientific reason to do this.
Oh, Puleeze!
Maybe you can sell your idea to the car Mfrs, who don't abide by this, nor do they recommend it for the new car purchasers.
Why? There is no need, just a bit slower break in.
Engines have already been dyno run, oft pretty hard before fitment (Chevy did it on Natural Gas in the 50s)
Clutches, gearboxes, diffs etc. all like a chance to get to know each other, but the acceleration/over-run techniques at half throttle and 2/3 revs should help this also.
80MPH on a new tranny and diff isn't probably the best.
Originally Posted By: Shannow
Originally Posted By: mechtech2
Originally Posted By: Scott_Tucker
I just bought a brand new Civic Si today and it will be broken in hard. Those who *really* know how an engine works know there is a scientific reason to do this.
Oh, Puleeze!
Maybe you can sell your idea to the car Mfrs, who don't abide by this, nor do they recommend it for the new car purchasers.
Why? There is no need, just a bit slower break in.
Engines have already been dyno run, oft pretty hard before fitment (Chevy did it on Natural Gas in the 50s)
Clutches, gearboxes, diffs etc. all like a chance to get to know each other, but the acceleration/over-run techniques at half throttle and 2/3 revs should help this also.
80MPH on a new tranny and diff isn't probably the best.
You bring up a very good point that you are not only breaking in the engine, you are breaking in the whole car. Transmissions, differentials, etc. need to be broken in too. The last thing you want to do with these things is overheat them while breaking them in.
My blunt statement that an engine should be broken in hard was partially just to stir the hornets nest because this is a topic I like to debate. I can't wait to pick up my Civic Si tomorrow, if you saw the roads I drive on every day, you'd know why.
Originally Posted By: mechtech2
Originally Posted By: Scott_Tucker
I just bought a brand new Civic Si today and it will be broken in hard. Those who *really* know how an engine works know there is a scientific reason to do this.
Oh, Puleeze!
Maybe you can sell your idea to the car Mfrs, who don't abide by this, nor do they recommend it for the new car purchasers.
Why? There is no need, just a bit slower break in.
Engines have already been dyno run, oft pretty hard before fitment (Chevy did it on Natural Gas in the 50s)
Clutches, gearboxes, diffs etc. all like a chance to get to know each other, but the acceleration/over-run techniques at half throttle and 2/3 revs should help this also.
80MPH on a new tranny and diff isn't probably the best.
You bring up a very good point that you are not only breaking in the engine, you are breaking in the whole car. Transmissions, differentials, etc. need to be broken in too. The last thing you want to do with these things is overheat them while breaking them in.
My blunt statement that an engine should be broken in hard was partially just to stir the hornets nest because this is a topic I like to debate. I can't wait to pick up my Civic Si tomorrow, if you saw the roads I drive on every day, you'd know why.
I never met a person who broken-in a vehicle by Driving-like-they stole-it that had a very long service life.
I used to work on light twin aircraft that were powered by turbocharged 540 C.I. engines. We would change the engines every so many hours. The new engines that went on needed to be broken in at higher power settings than normal, and we would tell the pilots to take the airplane up, set 75% power and fly it for an hour while keeping an eye on temps. What we wanted them to do is rupture the oil film on the cylinder walls so that the rings made some metal to metal contact.
The above procedure was right out of the maint manuals. You can find a better explanation of the whys and hows of break in right from the engine manufacturer here.
http://www.tcmlink.com/visitors/carenfeed/brkin.pdf
The idea is the same on automotive engines...
The above procedure was right out of the maint manuals. You can find a better explanation of the whys and hows of break in right from the engine manufacturer here.
http://www.tcmlink.com/visitors/carenfeed/brkin.pdf
The idea is the same on automotive engines...
Great article, MS21043!
On a production vehicle, it just doesn't matter. Moly rings, on the fine bore finish used, break in/seat in under a minute, literally. Assembled units are test fired, then run on chassis dynos after install to verify output and powertrain operation. The engine is well broken in by the time you experience that new car smell.
Comparing a car engine to an aircraft engine is an apple-oranges deal. Aircraft engines use a lot of chrome rings, different bore finishes etc. Chrome rings, with the rough bore needed to seat everything, benefit from high cylinder pressures to force the ring to "cut" the bore properly. I have seen successsful engine builders install pistons with chrome rings and the only lube used was a soak of WD-40. Oil was verboten on pistons and bores.
Comparing a car engine to an aircraft engine is an apple-oranges deal. Aircraft engines use a lot of chrome rings, different bore finishes etc. Chrome rings, with the rough bore needed to seat everything, benefit from high cylinder pressures to force the ring to "cut" the bore properly. I have seen successsful engine builders install pistons with chrome rings and the only lube used was a soak of WD-40. Oil was verboten on pistons and bores.
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