2019 Mini Cooper’s 1.5-Liter Three-Cylinder Engine: Likely Used
BMW’s petite B38 is often praised for its dependability and fuel efficiency, but even this trusted engine is not impervious to damage when mishandled. In this engine dissection, we will explore the underlying issues that caused a breakdown in this specific motor. The 1.5-liter three-cylinder has been utilised in a range of BMW vehicles, including the modest Mini Cooper Hardtop, the cutting-edge BMW i8, and the renowned 3 Series (in select regions).
The serial numbers on the motor indicate that it may possibly belong to a 2019 Mini Cooper. It shares a modular engine platform with various BMW motors, thus bearing similarities to the 2.0-liter B48 and 3.0-liter B58 engines used in all BMW models.
What caused the deterioration of this tripartite vessel?
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After conducting thorough investigations, no significant issues were found. While the gaps in the three spark plugs were slightly narrow, they were still within the acceptable range. Surprisingly, even the turbocharger appeared to be functioning properly, which is often a weak point in vehicles that lack proper maintenance. On the auxiliary side, the Valvetronic motor had been smashed and is the only concern.
A thorough inspection was required, and things got off to a good start when the tappet cover was removed, revealing a spotless valvetrain. Similar to a previous disassembly of a BMW N26 engine, the demonstrator in the video chooses not to dismantle the Valvetronic system in order to avoid diminishing its worth, and instead focuses on other possible issues.
The chains and guides were in satisfactory shape, exhibiting only minimal indications of usage (nothing unexpected), while the oil filter was also well-maintained, free from any traces of metal shavings or debris.
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Following a thorough examination of the cylinder head, the speaker proceeds to assess the engine block. Despite satisfactory conditions of most components, such as the oil, crankshaft, and bearings, the pistons showed evidence of skirt wear and an excessive build-up of carbon. With all other factors appearing in good condition, the speaker determines that the root of the engine’s malfunction can be traced back to this particular area.
The accumulation of carbon residues may be attributed to the burning of excessive oil. In the context of the B38 engine, malfunctioning piston rings could have led to the entry of oil into the combustion chamber, which ultimately resulted in its combustion. Ordinarily, such occurrences are uncommon in engines with low mileage, and there are typically indicators, such as blue smoke emission from the exhaust, that signal oil burning. Once again, it appears to be an avoidable engine issue that could have been prevented through adequate upkeep and servicing.
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