Cooling Fan Running After Turning Car Off?
Moderator
Joined: 01-23-2009
Posts: 26,448
From: Fredericksburg,VA
The 5 year shelf life of DexCool is pretty well established, may even be printed on the jug. That is life from the factory, not from installation.
My eyes don't lie (my wife does not agree) is the only proof of crystallization I need. When it over heats you will see lumps of stuff in the coolant. If it runs too hot and too long you will see a sandy sediment in the coolant recovery bottle and in the bottom of your pan that you drain it into.
My eyes don't lie (my wife does not agree) is the only proof of crystallization I need. When it over heats you will see lumps of stuff in the coolant. If it runs too hot and too long you will see a sandy sediment in the coolant recovery bottle and in the bottom of your pan that you drain it into.
Administrator
Joined: 10-13-2011
Posts: 39,900
From: Welland,Ont Canada
From this article
https://blazerforum.com/forum/engine...dexcool-88887/
and several members on this site.
https://blazerforum.com/forum/engine...dexcool-88887/
and several members on this site.
Senior Member
Joined: 08-03-2010
Posts: 3,564
From: Lake Ronkonkoma, N.Y.
I would like to know the scientific reason for it.
I have seen external slow leaks that do cause a crust of sorts that do look and feel like crystals.
I found a statement from an online auto mechanic forum where one person says it could happen in the engine, but he feels it's because the cooling system has air in it.
I have seen external slow leaks that do cause a crust of sorts that do look and feel like crystals.
I found a statement from an online auto mechanic forum where one person says it could happen in the engine, but he feels it's because the cooling system has air in it.
Moderator
Joined: 01-23-2009
Posts: 26,448
From: Fredericksburg,VA
DexCool is designed to do it. The assumption is: there is a leak in the system so it forms the snotty globs in an attempts to clog the leak temporarily, until the fool driving the car notices and fixes it. Unlike the old fashioned "green stuff" that tried to make a permanent fix and clogged the radiator.
Aged DexCool forms the sandy stuff, I guess that is just a chemical reaction. In my car it was enough to clog the overflow hose.
Aged DexCool forms the sandy stuff, I guess that is just a chemical reaction. In my car it was enough to clog the overflow hose.
Senior Member
Joined: 09-16-2013
Posts: 1,408
From: Tampa, Florida
There is no other reason for the fan staying on after shut down other than the car is TOO HOT
the engine should NEVER be able to reach temperatures above 217/219 under normal driving unless you are on a track day or something.
the engine should NEVER be able to reach temperatures above 217/219 under normal driving unless you are on a track day or something.
New Member
Joined: 01-12-2019
Posts: 23
From: Henderson, NV
113 Here monday, fan acts like it runs in lo gear after shut off, when I turn off the air before shutting down it doesn't run as long...
Running the Air will cause the fan to want to cool the head temp.
Running the Air will cause the fan to want to cool the head temp.
Thread Starter
Member
Joined: 05-23-2015
Posts: 70
From: Newton, NC
All I did was add some coolant and it has never done it again. I had a lot of top-end engine work done about 8k miles ago by my local Chevrolet store. That involved all new coolant, a new factory-temp thermostat and a new cap. I guess they just didn't fill it up all the way.
It was about a month ago when the fan came on but as I said it never has since.
It was about a month ago when the fan came on but as I said it never has since.
