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I appreciate the possibility that newer internal combustion engines (ICEs) burn more oil throughout their life. This appears to be partly due to using lower viscosity oils (which are being specified to achieve higher efficiency).

But I am also occasionally reading (on the wider web) that newer ICEs will burn off more oil during the break-in period. This is for example stated in this answer.

The oil consumption can be as much as 1 liter per 1,000 km during a running-in period of approx. 5,000 km if the engine is new or replaced (replacement of piston ring).

If it is indeed true that recent ICEs will burn more oil during the break-in period (5000? 10000? miles-kilometers?), why would that be so? What would consume oil during the first few thousands of the lifetime of an engine than the next stage of its lifetime?

My cast iron pans require an oil seasoning during the first several instances of use. This patina will subsequently protect the pan and will result in better performance (less adherence of food, for example). If I open a fully broken-in ICE and touch the cylinder walls, will I find a patina akin to cast iron pan seasoning?

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Sam7919
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Oil consumption during break-in is a very real thing, but it has nothing to do with a patina buildup canceling it out. It has to do with how rings seat in the bores and thus better seal. Getting cylinder rings to seat has been happening since the ICE was invented, so increased oil consumption during break-in is not a "new engine" thing.

When an ICE is put together, the cylinders are given what is known as a crosshatch hone. The specifics of how this crosshatch is applied has to do the cylinder wall material, ring material, and engine use. When it is first applied, the surface, on a microscopic scale is quite rough. You'd see the crosshatching, but you might not be able to feel it. As the engine is run, the rings wear into the wall smoothing it out and blending the ring face into the cylinder wall creating a very good seal. In most gasoline (petrol) powered there are two top rings which seal the compression and provide minimal oil control. There are two lower rings which provide oil control and virtually no compression. Until these rings seat, it will cause a bit of oil consumption. Some engines are worse than others. Some ring materials seat very quickly while others do not. All of these factors add up to different amounts of oil consumption as well as different lengths of time for seating to occur.

Some newer cars do burn more oil, but it has been my experience this has less to do with how the rings seat and more so having to do with the PCV systems allowing oil to pass through them. GM LS engines get a very bad rap for oil consumption, yet when the right oil control measures are involved, it's almost completely eliminated. I'm sure other "newer" engines get the same bad rap for the same exact thing.

Pᴀᴜʟsᴛᴇʀ2
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