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Moved from general (other diesels) to general tech discussion. Here are some more details : plainly put, roughly honed 2-stroke dirt bike engines that expand a lot due to being air cooled are not the same as the micro finished water cooled car engines which don't expand as much. Short life race engine and motorcycle engines are not the same as car engines designed to last 200,000 miles.

Everything you find in teh FAQ or stickied will be technically accurate and if someone can show why it's not accurate it will get fixed immediately. Disputed facts or subjective opinion won't get moderated, but things that are blatently wrong in the forums will get moderated. Here is an article about engine break in, I haven't linked it to 1000 answered questions yet because it's not yet finished. It should answer most of your questions.

In summary, always let the engine warm up with light load driving, don't boost the turbo hard when cold until the engine is warm. The piston-ring clearances and turbo bearings aren't warmed or lubricated properly when cold.


I will second that. When the engine is cold, you want to take it easy. Think of it this way - which gets more wear: a well lubricated engine or a poorly lubricated engine? When the engine is cold, it's not geting the best lubrication.

Which gets more wear: something that is held tight or something that is clanging around? The diesel pistons need to expand to tighten the piston-wall clearance. This is why a compression test with a cold engine will be different than a compression test with a warm engine. You could make the argument that you want to heat up the engine so that the clearances get as tight as soon as possible. This is correct, but getting into higher rps and keeping the turbo under boost is wrong, just wrong. That is taking the heat up the engine quickly to the extreme, especially on a new engine.

On any engine, broken in or not, let the oil circulate for 10 seconds, drive at light load until warm, then drive normally.
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