What Actually Happens When You Overheat an Engine

What happens when you overheat an engine? We pushed our BMW’s engine to the limit, then took it apart to assess the damage of an overheated motor.

Donut = We like cars, and we like making videos about cars. Hopefully our videos make you like cars too.

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[BorkKillsOneLegMan]

There are 3 things guarantee in life
1) Death
2) Taxes
3) *Donut destroying another engine*

[CarsGarage]

A man enters the race track and sees Jeremiah singing the USA's Anthem while overheating a German car.

[ツッ]

BMW owners taking extensive notes right now..

[samuelprusinski]

I used to have an e36. One day my fan went out and I was stuck in traffic. I had an obd2 reader on and was watching water temps and I got all the way up to 240 degrees and the needle still never moved from the middle. I’ve heard lots of stories of people blowing headgaskets before the temp needle ever moves. The e36 dummy gauge is so dumb it rarely ever moves

[yaboistewbot]

Petition to bring back science garage. ⬇️

[Machinehouseclips]

Engine mounts fighting for their lives 😂

[lukefleming]

The older BMW (E36 E46) engines are extremely solid, I'm not surprised to see that it held up so well. The problem with older BMWs is usually their use of crappy plastics that get brittle, crack/disintegrate when they fail and all of the leaks that occur while they're failing. -A former (and future) E46 owner

[TTM]

The graveside skit was funny as hell when you threw the wrench & the dirt on the engine.

[jwalster]

Fun fact: when you heat up metal to almost its melting point, and cool ot slowly, that is called annealing, which reduces the hardness if the metal and makes it more ductile. If you overheat and engine, and let it cool that has the potential to not fix all your problems and could lead to way worse problems if not checked out.

[PostTraumaticChessDisorder]

10:40 damn that sound effect brought back so many memories

His intrusive thoughts won. This is something I would wonder at 3 AM! 😂

[UltraRex]

Thank you for filming at 2160 P. Not enough channels are actually using the higher resolution.

[StormRoxas]

I love these kind of car videos. Take them apart and learn. Good stuff, guys

[shifty]

In the early-mid 00s when we were pushing the m52 headgaskets were our #1 enemy. I started calling all of us "hose squeezers" cause every time any of us walked past the car on the dyno we would squeeze the upper rad hose to see if the coolant system was pressurized. When we did the first 1000whp example we ended up O-ringing the block.

[Garcia]

This episode is top tier, you guys did good work and the camera work and edit is 10/10

[ElShotte]

This is the type of video that made me fall in love with Donut. Educational, entertaining, and awesome cast.

[dieselgaint]

Great tear down and explanation! I'll add something from my experiences. When removing the head bolts its a good idea to keep track of how tight, or hard, they are to loosen. Recently had a 2.4L toyota engine that was overheating. Went to remove the cylinder head and 3 bolts took almost no torque to loosen. Instantly new something was way wrong. Turns out the threads in the block pulled out due to the overheat. Ended up installing steel inserts in the bolt for all 10 bolts, and getting the cylinder head rebuilt. Car is running perfect.

[slyder]

Ik I'm a bit late to this, but I would genuinely love it if you could throw up more direct video comparison of the same tests but on a "good" engine. Like what does that water leak test look like on an engine with totally acceptable amounts of leakage so I can physically see how bad this one is, for example. Would greatly improve my ability as a viewer to relate with the content.

LOVE what you guys do!

[radsbosscraft]

This video hurt as a E46 owner as i feel like i lost a brother but at the same time it gave me more faith in my car to see that thing abused and honestly be "okay" and i learned a good bit about the engine so it was a worthy sacrifice

[JC_]

Donut is the only channel that can turn a mishap into an entertaining video ❤️