Engine Break-in

Any E46 owners out there know what the break-in procedures are for BMW? I have been told by some unreliable sources that BMWs don't need any special procedures for proper break in. This is my first new Bimmer and I want to get it right.

It's been awhile so it's hard to recall, but I believe the 3 series was keep it under a 100mph for the first 1000 miles or so and then also keep the revs below 4000-4500 for the same time limit.

I do vividly recall how hard it was to do as well. That baby just wants to keep on going and it is so much fun to let it run.

Enjoy your new ride.

-f

If memory serves me correct, the 100 mph 4000 rpm numbers are correct for the first 1000 miles. I did a Euro Delivery in 2000 and it was so hard to hold it back on the Autobahn, especially when there were other cars passing you like you are standing still.

I'm amazed at how many ED posts recently have pics of their speedos at 140+ mph. I almost wish they'd break these engines in prior to delivery....ALMOST!

Also, don't drive at constant RPM for too long - try to vary your engine speed. Definitely never use the cruise control.

Is break-in really necesary in this day and age? I mean, break-in even in the manual is only 'recommended'. For someone who's leasing the car, is there any incentive whatsoever to holding back during that first 1000 miles?

For leasing, no unless you want to buy back.

1. Don't go above 4500 RPM for the first 1000 miles.

2. Gradual Braking for the first 200 miles (New Brake pads)

3. No cruise control and keep varying your speed for the first 1000 miles.

4. Keep under 100 MPH for the first 1000 miles (I did not do this)

Its a pain to follow this but I guess it is worth it if you want to keep your car for a while.

so what happens when u don't follow any of these

cause dumb ass me never did

Originally Posted by Burakfb

so what happens when u don't follow any of these

cause dumb ass me never did

Self destruct sequence initiating in 5....4....3....2....

Originally Posted by Burakfb

so what happens when u don't follow any of these

cause dumb ass me never did

I think, these cars are built to last. May be you won't get 12 years out of your car, it might be 9. I don't know. At this point, I would not worry about that any more.

The deal with breaking in has to do mainly with the piston rings getting properly seated, as well as the various other moving parts on the engine that need to loosen up. If you gun around on a new engine there is a chance that the rings will seat improperly and your engine will consume more oil over it's lifetime. I know that Mercedes has engine racks that run engines prior to installing them in new vehicles. I was just wondering anyone ever heard of BMW doing something similar.

If you don't break-in properly, your might not have the 100% engine performance and braking power as its supposed to be.

I'm picking up my car in Munich next month. The performance package looks like it includes removal of the electronic speed limiter. I am planning on driving fast on the Autobahn, at least 150, maybe 200, if my copilot doesn't vomit. I'm thinking I'll drive within the breakin limits for the first half of the trip and be able to open it up on the return trip to Munich to drop the car off. With some planning I think you can have your breakin and speed it too.

There are several schools of thought on break-in procedures, but one goes like this - from a very experienced motorcycle mechanic who sounds like he knows what he's talking about.

1. The first miles are the MOST critical - you only get one shot to seat the rings, etc. So, you want to do this with the fewest possible miles on the odometer.
2. Ensure you've got proper fluid levels and warm up the motor and fluids to normal operating temp with sedate driving. This probably takes 15 minutes to get the gearbox and engine oil up there, regardless of what the water temp gauge says.
3. Using an empty road, late night on interstate, track, whatever - accelerate HARD in first and second gears. You don't want maximum revs, but with a say 6,000 rpm redline, hit 4,200 or so. NO BRAKES at this point - you want to let engine braking take you back to lower rpms. Repeat this several times.
4. Cool the motor down via normal driving then shutdown, check fluids, etc.

This sounds like it does several things you want - it gives you RPM variance, engine braking (loading the rings, etc.) and heat cycling all in one session. He claims significant improvements on the dyno and track times from bikes broken in like this versus the "traditional" method.

STRICTLY for informational purposes only - if all else fails, RTFM!!!!!!!!!!!!!!!

Originally Posted by volsfan0911

There are several schools of thought on break-in procedures, but one goes like this - from a very experienced motorcycle mechanic who sounds like he knows what he's talking about.



STRICTLY for informational purposes only - if all else fails, RTFM!!!!!!!!!!!!!!!

That's funny that you mentioned this guy, because that is why I asked the question to you guys. Apparently this guy is a famous engine builder. I don't see what harm it would do to try this out, considering most new cars are test driven the same way. Here is the link to this guys site. http://www.mototuneusa.com/break_in_secrets.htm

I wonder how much misinformation is in this thread?

Originally Posted by voltron1011

That's funny that you mentioned this guy, because that is why I asked the question to you guys. Apparently this guy is a famous engine builder. I don't see what harm it would do to try this out, considering most new cars are test driven the same way. Here is the link to this guys site. http://www.mototuneusa.com/break_in_secrets.htm

Yep - that's the guy. Personally, I broke in my current Accord the "traditional" way - took it easy for the first 1,000 miles (and it was awfully damned tempting to get on it but I kept south of 4,000 rpm). No cruise, pop the slushbox to 3rd around town for engine braking, etc. Used oil analysis at 15,000 on Amsoil was practically perfect (Honda V-6's puke copper early on). It eagerly sprints to 6,500 rpm now (friggin' slushbox), gets 31 mpg on the highway and I don't anticipate it burning any oil at all (neither of my previous 2 Accords did). However, I can't argue with his rationale and if you're not keeping the car long term (10+ years) then I can't see any serious harm being done. Engine braking is GOOD during the break-in period along with RPM variance and his method certainly gives you both.

Regardless of what school of thought you subscribe to regarding engine break-in (i.e. do it hard or do it gently) there is no justification for keeping vehicle speed below 100MPH during the break-in period as recommended in the owners manual (other than it is illegal to drive this fast or faster in most jurisdictions).

Originally Posted by Artslinger

I wonder how much misinformation is in this thread?

All opinions are true.

Originally Posted by Burakfb

so what happens when u don't follow any of these

cause dumb ass me never did

It it isn't using oil then it has broken in properly even if you didn't give any special attention to the break-in period.

For every dumbass that forgets about the break-in period there's another dumbass that turns it into a science project and then dumps the car after only a couple of years.

Originally Posted by virtualrain

Regardless of what school of thought you subscribe to regarding engine break-in (i.e. do it hard or do it gently) there is no justification for keeping vehicle speed below 100MPH during the break-in period as recommended in the owners manual (other than it is illegal to drive this fast or faster in most jurisdictions).

The engine isn't the only thing that needs to be broken-in. The reason for the 100mph limit is to allow the differential to time break-in. A new differential will run very hot under load.

Originally Posted by euro-d

All opinions are true.

opinion:

A personal belief or judgment that is not founded on proof or certainty

true:

Consistent with fact or reality; not false

Originally Posted by voltron1011

Any E46 owners out there know what the break-in procedures are for BMW? I have been told by some unreliable sources that BMWs don't need any special procedures for proper break in. This is my first new Bimmer and I want to get it right.

The most important thing to remember is to vary the speed in the first 1,000 miles. If on the highway move up to 60 or whatever and then back off to 45 or so. This approach will allow for a better "seating" of the rings and such. The worse thing to do is to put it on cruise contol and let it stay at one speed.

There is a couple of issues with the http://www.mototuneusa.com/break_in_secrets.htm article, it says do *NOT* use synthetic oil for break-in. If you know your BMW well, you'll know that all BMWs use synthetic oil. Are you going to drain that oil from your BMW because this MotoMan says you should for the first 1,500 miles breakin?

Also, he mentioned that you should *NOT* exceed 65mph during break-in. That's the definition on running the engine hard. That's well under the 85 mph recommended by BMW. Yes it's 85mph, not 100mph.

One thing many of you keep on forgetting is that, BMW has a huge group of extremely smart engineers working on the engine. They probably know more about their engines than any armchair engineers.

Originally Posted by phantom701

One thing many of you keep on forgetting is that, BMW has a huge group of extremely smart engineers working on the engine. They probably know more about their engines than any armchair engineers.

Amen. Why would anyone think that that Internet Motorcycle Motor Man knows more about what's best for BMW motors than BMW?

Unless you believe in conspiracy theories, thus believing that BMW is actually advising owners to do things that are bad for their motors or is simply making up advice with no basis, then why wouldn't you follow BMW's recommendations?

Oh I forgot -- if it's on the web it MUST be true