When to drive normal?

[ffgb]

I now have 1000-1200 miles on my totally rebuilt 1.6N/A motor.  Running good, not burning oil anymore because of the aggressive break-in the first 20 miles, followed by 3/4 throttle on upshifts and constant downshifting currently.  I am going to be driving from NORCAL to SOCAL this weekend on the I5 freeway and was wondering if driving on the freeway at a constant speed of 65-70mph to maximize gas mileage was ok?  Is it too early to drive at a constant speed?  Do I still need to vary the rpm's at this point?  Also, I have been using dino Shell Rotella 15W-40 since rebuilding this motor if this helps any.

Thanks

[745 turbogreasel]

To maximise your MPGs on 5, you'll need to run 75-85 so you can draft a semi

[Baron VonZeppelin]

After about 500 miles you're good to go.
By 1000 miles you should be good to do anything you want within the cars capability.

If you're still on oil change #2, i'd do #3 before the trip.

I've found best highway mpg to be between 55-60'ish.
But you might get run over on a busy highway in Cali at that speed.

Hope you have a good trip.

[Toby]

Running good, not burning oil anymore because of the aggressive break-in the first 20 miles, ....

Are you saying you think it is running well because you "busted it in" or that now it has finally quit burning oil which started after you beat the crap out of a fresh motor with 20 miles on it?

Beating the crap out of a fresh motor will often times get the rings bedded sooner than a proper break in procedure, but at the cost of shortening its service life by 75%.

A goon that wrecks, trashes. or scraps his stuff w/o getting much use out of things may never notice this, however. I hope no one here fits that category.

[ffgb]

I know you should break in the motor pretty-pretty good the first 20 miles and still be varying rpms by putting positive loads and negative loads on the piston rings for quit some time.  I drive fire engines.  When we get new ones, our mechanics tell us to drive the snot out of them, meaning 100% throttle, do not lug the engine, and do not let it idle other than for cooling the turbo down.  We have had brand new diesel motors in this rigs go out of service with only 2000 miles due to not driving the engines hard, essentially the rings didn't bedd in good enough and they ended up glazing and the motor just smoked like crazy.  Needed to rebuild/re-ring, that cost so much money!  I know on the freeway, at a constant speed, you really aren't loading the engine very much, that was my concern.  I just didn't know exactly at what safe point mileage wise was it ok to drive for a long time on the freeway, that's all.  I've heard 500 miles, 1000 miles, and sometimes 5000 miles before you should actually drive on the freeway for long periods of time, like as in 6 hours.

[deathhare]

One thing you have to remember when discussing this sort of thing is that everyone is an expert.

[Toby]

Toby, you should do some *current* research on how to seat rings and correctly break in an engine.  Aggressive break-in, if done correctly, does not hurt any part of the engine and will give a better ring seal for the life of the engine.

Says who? I have been hearing that same crap for 45 years and it has never been true before, so what has changed? While it is true that bore finishes are finer now than 40 years ago, I have never seen a case of so called " glazed cylinder walls" that was not attributable to running premium oil on break in. Of the hundreds of motors that I have done only 2 ever had the problem and both were initially started on Castrol XLR or GTX. These motors will eventually seat the rings but it takes about 10,000 miles to do so. Proper break in requires cheap oil for the first few hundred miles and many load/unload cycles of moderate speed and intensity. If you do that the motor will wear out the rest of the car. "Bust it in" and it will make more power in the first 5-10,000 miles than one that is still bedding the rings but it will be an oil burning toad by 20,000. If you are a spotty faced teenage goon you will never notice this because all of your cars end up in the crusher or traded for dope to some other spotty bottom git before you get that kind of mileage on them.

[rabbitman]

If you are a spotty faced teenage goon you will never notice this because all of your cars end up in the crusher or traded for dope to some other spotty bottom git before you get that kind of mileage on them.

Wow....... ........you are pitiful.

How about some examples of fast breakins that failed.

[Vincent Waldon]

Howsabout we take the growing hostility outta this thread. 

There are lots of schools of thought on engine break-in... and no one has a monopoly on the truth.  

[Toby]

Wow....... ........you are pitiful.

How about some examples of fast breakins that failed.

That depends on what you mean by failed. Does the engine blow up? No, they just wear out in pretty short order. I have seen dozens and dozens of "busted in" motors burning oil and losing compression by 20K miles where a good rebuild with good rings should go 200K. I used to specialize in Rabbit diesels and the ones that I let the kids break in always had short service lives. Read that: Lost enough compression that they needed new rings in a year or 2 in order to start when it was cold and they all had oil consumption issues. After that I always put the first 200 miles or so on a fresh motor and even the ones that kids drove lived long lives.

When I was a kid I did not have the patience to do a proper break in on my own stuff and it all had the performance tail off pretty early and all consumed enough oil that I had a blue haze following me around after 5 or 10K miles. Then I got talked into doing it like the book says, and viola, my engines started outlasting my cars instead of the other way around.

Nothing else changed. I still built motors the same way and I still drove them just as hard. The only thing that changed was break in procedure.

[Toby]

Howsabout we take the growing hostility outta this thread. 

There are lots of schools of thought on engine break-in... and no one has a monopoly on the truth.  

While no one has a monopoly on truth, data does not lie, nor does it engage in wishful thinking. This is not a matter of some touchy, feely, new age, "it worked for me" kind of thing. 2+2=4 no matter how much I want it to be 5. Schools of thought not backed up by data and experience are just armchair BS. Without a long term view of the data any conclusion is meaningless. It is also meaningless to compare race engines that get a teardown and get freshened up every few hundred miles with a car that you will put 50K miles on, not to mention 100K or 200K.

A race motor with mirror finish bores and moly rings has almost no break in time since the rings are so soft. But being so soft they are intolerant of ANY kind of grit getting into the motor and are susceptible to chipping the moly surface in severe duty.

That being said moly rings can last a very long time in truck and fleet applications where filter change recommendations are very closely followed. However most of us need something harder, like chrome rings, and these take longer to bed. Hard rings are vastly more durable and have greater longevity than softer stuff. Cast iron rings are for tractors and old junk and have a much shorter service life than chrome.

[Mark(The Miser)UK]

An interesting break-in site...

http://www.mototuneusa.com/break_in_secrets.htm


 

[Toby]

Well, he is correct for RACE engines that get torn down on a regular basis. This might also be OK on a sport bike with moly rings (or some other high tech soft material), very smooth bores and very tight air filtration. It is important to remember that sport bikes have roller everything with the rings being the only real sliding interface if the engine has roller cams so there are fewer places to shed metal into the oil.

He is also correct that babying the motor is not proper break in procedure. In order to get optimum seal over the service life of a non race motor you need varying speed and load and periodic deceleration to wear in all faces of the ring/piston/bore interface. I would also add that very slick oil is not a good idea in the first couple of hundred miles.

As for his magic pistons; they are clearly faked. No engine has that tight ring set. I have had hundreds of motors apart, some with 2% leakage and never seen a piston with absolutely no color above the top ring except for Dykes/head land rings. Some of these motors were broken in with "his" method.

BTW: this used to be the break in directions on the box for Ramco moly rings; they are not new and he did not think them up.

[doonboggle]

AMEN ! !

All I know is that on the TDI club forum, the fellows ... without vitriolic comments ... advise that after a normal break-in of a thousand or so ... to then ... "drive it like you stole it!"

My 2cents worth.....

To the poster ... enjoy the drive.  That's my old beat when with the CHP in Newhall; Gormon summit down what used to be called 'Grape Vine'.  No longer that now.....

Howsabout we take the growing hostility outta this thread.  

There are lots of schools of thought on engine break-in... and no one has a monopoly on the truth.  

[theman53]

Yeah what he^ said...
it is if OM617 registered under a new name.