What could happen if someone doesn’t let an engine warm up?
In: Engineering
I didn’t let my motorcycle warm up enough one morning. It stalled as I was in the middle of making a right turn on to the main street off of my block. Almost dumped the bike right there.
Honestly it’s to get the heat started in the car cuz it takes a while for the heater to turn on from a cold start
I have been told by many mechanics that about 10-20 seconds before putting it into gear.
Reasoning is to let the oil/tans fluid to cover the parts.
Less guessing and more facts people.
Warm up is crucial for engine longevity. Pistons made of aluminum absorb heat and change size faster than your iron block. Cold start and quick high load makes the piston contact the cylinder wall causing wear.
Two stroke Detroit diesel engines used cast iron pistons and blocks so they would expand at the same rate. Thus making them superb for emergency vehicles (fire trucks) that need to go balls out as soon as they are started without compromising longevity.
And this isn’t just a winter thing. A 105° August day is not up to operating temperature for the internals for engines.
I don’t even own a sweater where I live. I still let my car warm up though.
Glad to know this is completely unnecessary.
There are a few reasons.
When metal heats up, it expands. The pistons in an engine can heat up rapidly under heavy load, so much so that they may heat faster than the cylinder walls.
If that happens, the piston will expand faster than the cylinder and damage/scoring can occur.
If the engine is warmed up gradually to operating temperature, then the components will expand more uniformly.
Another reason is oil being much thicker when it’s cold. Cold oil is harder to pump into all of the small passages throughout an engine, so if you put an engine under high load with cold/thick oil, you risk damaging the bearings and other parts that need oil to survive.
A lot of people are mentioning fluids and air-fuel ratios, but I think the other issue is also the metal that makes up a lot of the engine parts that need to warm up.
Taking cold metal and applying a sudden increase in temperature and pressure to it could potentially lead to catastrophic (and premature) failure of those parts.
I warm mine up unattended for 3-5 mins, mostly so I am less cold when driving. I live in Minnesota so you can imagine the cold.
Most people actually do this not to warm up the engine to prevent engine damage, but to warm up the engine so your heater is working. Nothing worse than driving in an ice cold car waiting for the heater to actually send warm air through the vents, and meanwhile your windshield is frosted over because the air trying to defrost the windshield is fricken cold. This is why Canadian cars still have block heaters. Your engine is fine, but your butt is icy.
OK but which of these answers are relevant to me, a resident of the Canadian prairie winter hellscape, which gets down to -40° ?
Are the answers still generally relevant or are there additional considerations at that temperature?
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