Gnarly BMW Engine Teardown Shows The Dire Consequences Of Overheating

BMW N26 Engine Teardown

The block is scrap because the damage would cost more to fix than it’s worth.

If engines could talk, we’d love to hear the story this BMW N26 turbocharged 2.0-liter four-cylinder would tell. The powerplant is the star of the latest teardown from the I Do Cars YouTube channel.

From the start, the engine looks rough because there’s a big hole in the valve cover. The channel’s host Eric says this happened during shipping, not because of a catastrophic failure. It also came delivered with the turbo barely attached and a bunch of loose bolts. Not a great start.

Markings on the block suggest this engine came out of one car and into another before coming to Eric as a core for him to tear down.

There’s an early indication of what’s wrong with this engine because one of the heat tabs is melted. They do so at a specific temperature as a quick, visual indicator that the powerplant overheated.

Taking the engine apart reveals some weird details. For example, some of the fasteners don’t match, which is not how things would come from the factory. For example, the plastic timing chain guide’s manufacturing date shows 2022, meaning someone must’ve been working on this mill, since the engine went out of production in 2016.

The video gives us a fascinating look at BMW’s Valvetronic variable valve lift system. It’s essentially a camshaft on top of another camshaft with a gear-driven shaft in between. Eric doesn’t take the components apart because his main job is selling engine parts, and this piece is more valuable as a whole. However, his delicacy with this piece turns out to be a waste.

Taking off the head reveals serious trouble. There are burnt sections between each cylinder and similar marks on the upper edges of each bore. This is an obvious case of the engine overheating. According to Eric, it would cost more to fix the block than the piece is worth, so the metal is going to the scrap yard.

Weirdly, there are pieces of plastic in the oil pan, and there’s no discernible reason for this. Eric hypothesizes they could be from a previous repair. He then takes a closer look at the cylinder head. There are several hairline cracks between the combustion chambers and the valves, meaning most of this piece is junk, too.

The whole story of this engine is a mystery, though, as we don’t know where it came from. Let us know what you think happened in the comments below.

Want More Mechanical Carnage? Watch These Teardowns:

Source: I Do CarsYouTube