Truth or Myth: Modern Engines STILL Require Break-in

[Trav]

Frank, on this forum and others common sense may be in very short supply with some posters. Anyone claiming today's machining process is cleaner than years ago is clueless, with plexiglass guards and wash tanks it may be cleaner for the operator and the working environment (which may help prevent metal trash getting into the engine when assembled) but the fact remains machining metal is a very dirty business.
The metal parts are still going to have very small machining marks that need to be mated as the engine runs regardless of how precise the initial fit is, the microinch surface rating is not going to be the optimal for a surface finish in mass produced engines due to the higher cost and machining time restraints, it may be a little finer than the old days but far from optimal.

 

[TiGeo]

Frank, on this forum and others common sense may be in very short supply with some posters. Anyone claiming today's machining process is cleaner than years ago is clueless, with plexiglass guards and wash tanks it may be cleaner for the operator and the working environment (which may help prevent metal trash getting into the engine when assembled) but the fact remains machining metal is a very dirty business.
The metal parts are still going to have very small machining marks that need to be mated as the engine runs regardless of how precise the initial fit is, the microinch surface rating is not going to be the optimal for a surface finish in mass produced engines due to the higher cost and machining time restraints, it may be a little finer than the old days but far from optimal.

Nobody here is saying an engine doens't break in nor does it generate metal particles. What some of us are saying, that appears to fall on deaf ears, is that changing your oil early to deal with this clearly isn't doing anything of value b/c if it was, the vast majority of owners that don't do this would see fall out which, that I can find in my lack of common sense self, isn't happening. If you think they is good to do, by all means, do it. But for those of us that don't and have had repeated vehicles with high mileage without lubrications issues, we aren't lacking common sense b/c we don't follow the BITOG hive mind of the oil illumaniti..errr...experts....I still want to know what mileage for that first change makes my engine last forever...100? 125.5? 50? 25.78 (repeating)? Clearly it isn't 7K or whatever I've done on the last few new ones I've owned that seem to not have any drama with their scored cylinder walls from all that metal pass through the filter...

IBL!

 

[KrisZ]

Nobody here is saying an engine doens't break in nor does it generate metal particles. What some of us are saying, that appears to fall on deaf ears, is that changing your oil early to deal with this clearly isn't doing anything of value b/c if it was, the vast majority of owners that don't do this would see fall out which, that I can find in my lack of common sense self, isn't happening. If you think they is good to do, by all means, do it. But for those of us that don't and have had repeated vehicles with high mileage without lubrications issues, we aren't lacking common sense b/c we don't follow the BITOG hive mind of the oil illumaniti..errr...experts....I still want to know what mileage for that first change makes my engine last forever...100? 125.5? 50? 25.78 (repeating)? Clearly it isn't 7K or whatever I've done on the last few new ones I've owned that seem to not have any drama with their scored cylinder walls from all that metal pass through the filter...

IBL!

Not sure what fallout you’re looking for here. The old “roads littered with broken cars” as the only acceptable proof.

Just look at how wide the engine specs are, like oil consumption, compression. Fuel dilution is not even on the radar. Most engines will run happily on 120psi on each cylinder and most people wouldn’t notice. How many engines burn oil but the owners ale oblivious to it? How many will have a cat efficiency code prematurely?

Yes, in the grand scheme of things, as long as the wheels are turning, most people do not care that their engine is not operating at its peak performance levels, but that cannot be used as proof that there is no tangible benefits to be had.

It clearly matters in applications where it is critical that the engine reaches the rated performance levels.

 

[Cherrybomb]

Thank You KrisZ for the link to Aircraft Engine Break In,that to me was a lot of interesting reading.No matter what,why we personally do what we do to our vehiches it's much easier.Of course they have a bit more risk and cost.I'm a big believer in oil analsis and it kind of surprises me the aircraft people didn't mention it in that article.

 

[KrisZ]

Thank You KrisZ for the link to Aircraft Engine Break In,that to me was a lot of interesting reading.No matter what,why we personally do what we do to our vehiches it's much easier.Of course they have a bit more risk and cost.I'm a big believer in oil analsis and it kind of surprises me the aircraft people didn't mention it in that article.

You’re welcome.

Few things on the aircraft industry.
They have to adhere to a very strict maintenance, inspection and replacement regiment based on hours of operation or the number of take offs and landings.

The engines have a finite number of flight hours and after that they need a full rebuild regardless of condition. That is why they don’t tinker with UOAs. There is no need and it’s just an added expense.