I know engine temperature must go down to "C" mark before opening radiator cap.

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However I"m finding the the temp simply stays on typical for a lengthy time. I think I"ve read civilization say you need to offer an engine 30 minutes or so come cool down prior to you drain oil. But after an ext than 30 minute my engine temp is still on normal.

Is this normal? just how long have to I wait prior to I can expect an engine come cool down? When must I take into consideration that I could have a problem and also what type of problems might reason long cooling?

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edited Oct 10 "18 in ~ 13:03

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asked Oct 10 "18 in ~ 12:47

James WilsonJames Wilson
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The specific time taken counts upon assorted factors:

The ambient temperatureThe amount of heat insulation in the engine bayVolume of coolant in the engineHow hot the engine acquired while drivingmaterial provided in building of the engine block/head (aluminium blocks cool faster than steel for example)

and many much more besides.

Typically despite it should be left to cool because that 1-2 hours prior to it"s cooled sufficiently to open the rad cap safely. If you"re in reality trying to check the coolant level climate you more than likely need to wait an ext like 3-5 hrs (as if the coolant is still warm it will display a falsely high reading because of expansion).

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I realise the sounds prefer an awful lengthy time yet you need to remember that after you turn the engine off a fair chunk that the residual heat from the engine is actually still gift passed come the coolant (which is no surprised as the raison d"être that coolant is come remove heat from the engine!) and also since you room no longer running the water pump and rad fans (in most situations - part cars will have after-run systems for these. Mine still runs the fans for quite along time after ~ ignition turn off if the automobile has to be driven hard for example) and also there is no much longer any far-reaching airflow end the radiator (unless the wind happens to be blowing that method I guess) the cooling system"s capacity to remove heat from the coolant is a currently purely passive and also a fraction of what that is as soon as the automobile is running.

The factor you deserve to do engine oil alters after only 30 mins is because you aren"t wait for the to it is in "cold" - in reality oil is much less complicated to readjust while still warm as viscosity drops and also it will drain much easier and faster.