Tips for braking-in the rebuild motor??

[zero2]

Newbie on 02,

Just got my rebuild motor.

Are they any specific process on starting for the first time?

Anythings I should or should not do before start pouring the oil into the head?

The guy who rebuild the motor to told me use 10-30 mobile1 synth for first 1500 miles and drive the car normal to hard. Then 20-50 or 40 mobile1 synth every 5000 miles. Mobile1 synth 75-90 for the manual gearbox. Does it sounds right for Florida Car?

Your input will be really great, I spent a lot of my time and hard earned money into this project.

[Guest Anonymous]

Newbie on 02, I am just pick up my rebuild motor. Are they any specific process on starting for the first time? Anythings I should or should not do before start pouring the oil into the head? The guy who rebuild the motor to told me use 10-30 mobile1 synth for first 1500 miles and drive the car normal to hard. Then 20-50 or 40 mobile1 synth every 5000 miles. Mobile1 synth 75-90 for the manual gearbox. Does it sounds right for Florida Car? Your input will be really great, I spent a lot of my time and hard earned money into this project.

It sounds as though you doubt the advice given by the engine rebuilder. If you have no confidence in the advice, maybe you should not have bought the rebuild. Besides, if something happens to the engine and you did not follow the advice, will the rebuilder stand behind his/her work?

Since I for one, have no idea how things were rebuilt, tolerances used and parts used, it is but a guess and probably unfair to the rebuilder.

Conventional wisdom is to use 20-50W non synthetic at first - look at your owner's manual. That doesn't mean using straight 30 weight wouldn't work. Standard practice as to breaking in engines can be found in most manuals, including those offered by BMW, Haynes, AUtobooks, Chiltons etc. You can also find a plethora of opinions in the archives.

[rogerspeed]

Gearbox first, 75-90 synth OK if GL-4, like redline.

From experience, having had rebuilt a number of m10 and ALFA 2 liter motors rebuilt, the break-in oil should be natural or blend not straight synthetic, weight 10-40, and follow the instruction for break-in at the time the motor was new from the factory. 3000-3500 rpm redline first 500 miles and very engine speed, change the oil (20-50), next 1000 - 1500 miles, 4000 - 4500 rpm redline, change oil again, then drive the way you want. If you "taste" the power too early, the motor (and you) will not be happy

[c.d.iesel]

-= DO NOT USE SYNTHETIC MOTOR OIL DURING BREAK-IN =-

Use 10w/40 mineral oil for 500 - 900 miles

Re-Adjust valves COLD at first oil & filter change

Use only BMW oil filter #059, or other 'german' MANN brand oil filters.

Check ALL engine, exhaust, intake, mounting hardware for tightness

at this "FIRST SERVICE"

At this "FIRST SERVICE" - use the oil you want - 15W50 MOBIL 1 would be

my choice - and or any 20W50 oil - mineral or synthetic.

only SAE 75/80 GL-4 gear lubricant in your trans - unless it's a 'later' 5-speed, in which ATF is also approved

only " HYPOID" SAE 90 Gear OIl in the steering gear and rear diff

Flush the clutch and brake system at the "first service" and then

every year thereafter

Have Safe Fun

C.D.

[BobBreed]

I assume that this engine has not been installed? If so, make sure you crank the engine over with the coil wire removed until you have oil pressure. Then fire it up. In the shop, we use Rotella T 15-40 as our break in oil. It has engough Zinc in it. After that, Mobil 1 is fine. Personally, I'd go with redline over the Mobil 1 just because of the zddp.

Bob

[Guest Anonymous]

CD (sorry you sold it!):

As always, your advice seems good and detailed. But you are assuming the engine was rebuilt just as BMW intended it to be rebuilt 30 years ago. You, yourself, have acknowledged, BMW occasionally has a change of mind regarding its recommendations. One big example is BMW's revised head bolt torquing procedure which you brought to my attention. Could it not be that BMW might change its recommendations if the engine were rebuilt using newer style/design custom pistons, rings, and machined to tighter tolerances than were offered in 1970? I mention this not to disagree with you for the sake of disagreeing, but my newer cars have far different factory recommended break-in procedures. My Porsche came from the factory with synthetic oil.

If the engine rebuilder of the subject rebuild used custom pistons, custom piston rings and tighter machining tolerances, maybe that alchemist-rebuilder really has a better idea. He or she may also be a quick buck fool too. I would bet that many professional engine rebuilders differ in both their rebuilding methods and this includes break-in. This might even include the extreme examples of people who allegedly run their engine hard at the very first start to immediately break OR break-in their engines as has been suggested by some self-described motorcycle mechanic on the net.

[neanderthal]

when i had my motor rebuilt i was given the same advice that CD has given; namely, dont rev it past 4000 until the 600 mile oil change. then i could rev it a little higher (5000 rpm) until 1500 miles. and another oil change. then i could drive it as i wanted, but not to redline until 3000 miles. after that oil change i could then feel free to drive it to redline and use synthetic oil.

i was also told to vary the engine speed as much as possible during the first 1500 miles, so i avoided using freeways, and on the occasions when i did use the freeway (after the 2nd oil change) i made sure to stay vary my speed between 60 and 80 and to also occasionally use 3rd gear to break upi the monotony of driving at one speed.

its been Mobil 1 ever since that 3000 mile oil change.

[TobyB]

If you follow your builder's instructions, you'll have a much better chance

of getting support if something goes wrong.

If you disregard said instructions because of something you read on

some bulletin board somewhere on the internet, she or he may not be as

helpful in the event of a malfunction.

That said, I'd stop back and confirm (in writing is best, even if you just

take notes in full view of said builder) that Mobil 1 10-30 is best for break- in.

Because it doesn't fully agree with 'accepted internet wisdom'

as it applies to slider cams and rings...

Proceed with caution!

t

[KFunk]

Here's an important link that refutes the traditional wisdom that you should break in a motor easy:

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

I've just been running my freshly rebuilt motorcycle engine at 10K RPMs quite regularly.

[Guest Anonymous]

KFunk, you cited the very guy to whom I was alluding. There are a few others, too. When I first read this I wondered if it wasn't another manbeef ad.

Your representation of running your NEW engine at 10,000 rpm seems to be an unqualified endorsement. Does this mean you are a convert? Have you subscribed to Motoman's publications? What have you learned aside from the information he makes public?

I do not have the guts to try the theory but wonder if it has validity, why haven't the manufacturers followed suit? For what its worth, I have built quite a number of engines and a few that I have followed are still going strong 25 years and many 100's of 1000's of miles. I have babied them all, to the extent I had any control over them.

Please provide more details.

tia

[KFunk]

KFunk, you cited the very guy to whom I was alluding. There are a few others, too. When I first read this I wondered if it wasn't another manbeef ad.

Your representation of running your NEW engine at 10,000 rpm seems to be an unqualified endorsement. Does this mean you are a convert? Have you subscribed to Motoman's publications? What have you learned aside from the information he makes public?

I do not have the guts to try the theory but wonder if it has validity, why haven't the manufacturers followed suit? For what its worth, I have built quite a number of engines and a few that I have followed are still going strong 25 years and many 100's of 1000's of miles. I have babied them all, to the extent I had any control over them.

Please provide more details.

tia

Max,

I haven't really had the chance to break-in any re-built or new car engines unfortunately (or fortunately?), so I really can't offer much qualified advice myself. I'm still trying to blow up my 02 engine so I can re-build it, but running the crap out of it with no rev-limiter still hasn't done it.

For my bike engine, I'm mostly following the recommendations of a company that re-builds and races engines exactly like it, and their break-in procedure is similar to Mototunes. They've gotta struggle to get the most power out of tiny motors so they can win races, and so they've probably been thru plenty enough engines to learn whats best.

I just did the break-in Friday night, and Saturday night I rode it at 9 to 10K RPM for 5 miles or more, and she's holding solid so far. I can't tell if there's much more power, but the sound is very different, more of a popping sound that lets me know the compression is better.

[Guest Anonymous]

Thanks for the response.

I used to work near a shop that specialized in building engines primarily for offshore racing, but they worked on all kinds of things. They were very sterile and secretive about their workings, maybe to keep ahead of competition or maybe to add some mystery for the customer's benefit to justify their high prices. While you could see the parts being laid out and polished and weighed, some things were strictly off limits and need to know basis. One thing that I enjoyed watching was the testing of the engines on an in-house dyno. I mention this because they would run these brand new engines throughout the rev range for horsepower and torque ratings.

Doing this seems very much in keeping with Motoman's theory. Of course, the engines were presumably extremely well built and not designed for long term use, so the theory may not hold that much validity from an engine we might expect 25+ years of decent service.

[zero2]

Jerry

Is not that I did not have the confident in the the guy who rebuild the motor, I will not had got the motor from him If I did not. He works on BMW and Benz. It just that he did not own a 2002. That why I want to get an opinion from guys who own them.

MaxSil .50mm oversize pistons were use on this M10 with E12 head.

Thanks for your input!

It sounds as though you doubt the advice given by the engine rebuilder. If you have no confidence in the advice, maybe you should not have bought the rebuild. Besides, if something happens to the engine and you did not follow the advice, will the rebuilder stand behind his/her work?

Since I for one, have no idea how things were rebuilt, tolerances used and parts used, it is but a guess and probably unfair to the rebuilder.

Conventional wisdom is to use 20-50W non synthetic at first - look at your owner's manual. That doesn't mean using straight 30 weight wouldn't work. Standard practice as to breaking in engines can be found in most manuals, including those offered by BMW, Haynes, AUtobooks, Chiltons etc. You can also find a plethora of opinions in the archives.

[Pinepig]

Here's an important link that refutes the traditional wisdom that you should break in a motor easy:

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

I've just been running my freshly rebuilt motorcycle engine at 10K RPMs quite regularly.

Use this method, last two motors I built I used this method and it resulted in strong motors with very low oil consumption.

[Guest Anonymous]

I have heard this break-in theory for years and wonder why auto manufacturers didn't encourage the same thing - if it worked. Repair frequency would have been reduced and engine longevity might be enhanced. Then again, maybe there were fears that all customers would be speeding to break-in their engines.

Motoman's theory seems premised on the notion that piston ring break-in is everything or nothing. Rebuilding or building a motorcycle engine can certainly be time consuming and expensive. However, those parts tend to reach operating temperature much quicker than auto engines, they also (air cooled engines) tend to be aluminum alloy designed for greater expansion and contraction. They also can be torn down easier, than our cumbersome blocks if something goes wrong.

We all know that piston rings and honed cylinder walls are designed to wear together. If they are not burnished evenly or gradually, and knock on wood, you score a cylinder wall, this process only accelerates things. If the scoring is minor, I would think a rotating piston ring might even things out. I just don't know. The wear created by harder break-in might increase the number of metal particulates in the oil so that nice and tight bearing surfaces might be affected too, warranting an immediate oil change. When I learned to build and rebuild engines, we were taught secrets such as revving an engine without a load on it was a terrible thing and could damage camshaft lobes and journals. Some of us took these things for granted. Conversely, there must be a tremendous amount of acceptable tolerance to internal combustion engines, because I have torn apart running engines that defied all logic given their enormous wear.