Specifically a 3.0 that has 900 miles on it. It has not had its oil changed (don't know if it is dyno or synthetic), now has it had its headbolts checked. Thanks

 

If you don't get your foot into the throttle enough the rings never fully seat and the motor will burn oil forever. And you should change your oil right away! Suggested oil changes are right after start-up and inital driving around, 500km's, 1000km's and 2500kms to be safe. And you should use a w30 oil with no additives, or just use royal purple break-in oil

 

Cons to not properly breaking in an engine are premature wear, which will lead to premature engine failure, poor performance, poor fuel economy, higher emissions, etc. Just go easy for awhile, and you should be golden. Keep up on those oil changes too!!!

 

I'm almost ready to fire up my freshly rebuilt and the mechanic with 40 years building motors told me the first 20 miles are the most important. He told me to get it running, time it as fast as possible and get it up to tempurature and go out and floor it. He said (and showed me in writing) to drive it in second gear and floor it up to just below redline. And to repeat the process 8-10 times, but he said more won't hurt it. Then get it home and drain the oil. Also, don't stay at the same speed/rpm while driving and don't let it sit at idle for too long

 

first 500 miles...drive it like theres 100lbs of cocaine in the back and the cops are about to get you...lol as in drive it like you stole it..

lots of trips to redline..

run it to redline in every gear you can and let off the gas and let the motor slow the truck down, do that about 10 or 12 times every now and then...and yes never stay at the same RPM for long..


while sitting still and holding about 4000 rpms...my truck starts to smoke pretty good (blue smoke..oil burn) after a few seconds...i reckon it's cuz i was told to take it easy for the first 500 miles or so....which means the rings have not seated and prolly never will..

 

I think most of what is written about "breaking in" a new or fresh engine is either obsolete or nonsense. One example is anew Corolla I bought a couple years ago. Ownesr manual advises don't maintain steady speed for first few hunderd miles. So I got it with 11 miles on it and drove it 900 miles at 70mph next day. Two quick stops for gas. Result after 23,000miles: it uses no perceptible amount of oil between changes (3 months/3,000 miles) and gets 39-43 mpg depending on whether its winter or summer and whether I'm doing 60 to work or 70 on a long trip.

If the cylinders are accurately machined and surface finished, and proper fitting quality rings are installed, its "broken in" after its cranked for starting.

 

I think that's probably one of the most important things right there. I've only broken in Jetskis and motorcycles (and an ATV) but that was one of the specifics of breaking in the engine.....along with avoiding full throttle operation for the first 5 hours. There weren't any real requirements for speed or anything.

 

The only thing that occurs when breaking in is seating of the rings. Because of the precision in todays engines it is unlikely a ring will not seat correctly however. All manufacturers advise an easy break in, something I have never really understood. Most manufacturers seem to advise a REV limit for the first 1,000Km. Im usually not one for conspiracy theories but my honest opinion is that mass production car manufacturers want the car to survive past warranty and that is it. They dont make money of 20 year old cars you see... True or not I prefer to take my cues from performance companys such as Lamborghini/porsche etc. Before the engine goes in the car it is run through computer testing under load, at high RPM etc...pretty much every real world scenario you could think of. Once the engine is installed the car is graciously smashed around the test track before delivery. These guys know what they are doing, there cars are built around performance at all costs unlike the compromises that mass production companys take to cut costs at every corner.

Regardless of how you break in an engine regular oil changes are the MOST important thing you can do.

 

I have heard that the ring seating is a theory that belongs to way older engines than ours. But it never hurts to be on the safe side.

And you don't need to do anything to the head bolts.

 

I bought a set of Hastings rings for a Ford 302 several years ago and that is almost exactly what the instruction sheet said to do.

 

On new sportsbikes, I warm the tires up and redline it
When sportbikes get built, they have a guy whose sole job is to roll the bike on a dyno, hookup the diagnostic, and run the snot out of it.

On car motors, I go easily but pull it to 75% RPM range steadily.
Put it in low gear, higher RPM, and go out late at night getting on and off the gas.
I would cycle the engine to hot and let it cool off for a few times, with one or two oil changes. That's the way I do it and it's different for everyone. There you have it

 

Not in my case. I'm using a new cam.

What confuses me is cam manufacturers seem to call for a 15-20 minute run or several idling at 2K or so to break in the cam, yet to seat rings apparently we're supposed to get under load as soon as the engine is warm. Any thoughts on this?

 

Very interesting. Maybe an email to Ted is in order?

 

break in the cam then change the oil.assembly lube they say can plug the oil filter. after that break in the rings like everyone above states. then just drive it in all ways possible. just change the oil three times or so until 2000km oil changes are cheap compared to motor rebuilds.

 

wow im really glad i seen this thread. i go tmy yota in the shop gettin rebuilt. i would have figured you drive it like a granny to break it in. but your guys ways sounds a whole lot funner

 

yea man, run the piss out of it for an hour and doing the things that people have said above, change the oil right away and keep up on the oil changes!!!

 

The last engine I "really" had to break in was a 2.3L Turbo in a Mustang. They did the initial start-up / oil change. After that, all they advised was avoid full throttle AND high RPM for the first 500 miles, and get the oil changed at 500 miles and 1500 miles. I changed the oil filter and topped the oil up at 250. At 1500, the oil was still full so just another filter change and top-up. About 3000 miles later the clutch started slipping so I traded it in. I suppose the engine was making good power.

The problem with breaking in an engine is that things move around... and in particular, the rings. You want the rings to settle as soon as possible before they have the chance to rotate around and get their end-gaps close to each other. Repeated quick, hard, full-throttle runs in high gear (heavy throttle without winding the engine up) with appropriate deceleration periods (high engine vacuum with foot off the pedal) tend to take care of that rather quickly since that will cause some carbon build up on the rings which in turn helps keep the rings from spinning around the pistons.

 

Moved to the General Vehicle Related Topics section.

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That makes sense, never heard a good explanation before.