HELP? Radiator fan has a delayed shut off

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Jun 27, 2007 | 07:57 AM

S4 in_lowplaces

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HELP? Radiator fan has a delayed shut off

Got home from a 45 minute drive last night, AC was on. I pulled up into my driveway and when i shut the car down the clutch fan, or the belt driven fan continued to run after the engine was off, It ran for about 5 seconds then it shut off. I turned the car back on let it idle for 30 seconds then shut the engine off, ran to the front and i noticed it was one of the two fans behind the radiator kept spinning for 5 seconds again then shut off. Came to work this morning with AC off turned the car offf and the problem was gone. Any Ideas

Jun 27, 2007 | 08:11 AM

2000SForce

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afterrun pump it's fine

Jun 27, 2007 | 08:39 AM

S4 in_lowplaces

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well i know about.....

the after run pump that turns on when engien temps are to high.This isnt the case, its just a delayed shut off for the fan nehind radiator.

Jun 27, 2007 | 09:58 AM

WECoyote-SuperGenius

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I'm guessing that the electric fan is activated by a thermal switch that is over-rided by the .....

use of the a/c.
When a pre-set temp. is reached, thermal switch turns on the electric fan, when the a/c is on the electric fan will engage regardless of thermal switch temperature. When you shut off the engine, coolant and oil temperatures usually spike (increase a bit) because the engine fan has stopped and the engine coolant and oil have stopped circulating.
The electric fan does not need the engine to be running to activate, hence the warning stickers about not sticking your hand in the fan and why when working on the fan you should disconnect the battery.
Nothing to worry about.