# Bleeding the air out of a cooling system

**URL:** <https://community.cartalk.com/t/bleeding-the-air-out-of-a-cooling-system/88571>\
**Category:** General Discussion\
**Created:** [January 5, 2015, 6:18am UTC](https://community.cartalk.com/t/bleeding-the-air-out-of-a-cooling-system/88571 "2015-01-05T06:18:11Z")\
**Posts on this page:** 11\
**Page:** 1

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**Author:** ![dodge330](https://avatars.discourse-cdn.com/v4/letter/d/ec9cab/32.png) [@dodge330](https://community.cartalk.com/u/dodge330)\
**Post date:** [January 5, 2015, 6:18am UTC](https://community.cartalk.com/t/bleeding-the-air-out-of-a-cooling-system/88571/1 "2015-01-05T06:18:11Z")

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I heard that you could place a flat screwdriver between the upper radiator hose and the end of radiator. Is this procedure really work?

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**Author:** ![SteveCBT](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/stevecbt/32/3192_2.png) [@SteveCBT](https://community.cartalk.com/u/SteveCBT)\
**Post date:** [January 5, 2015, 6:24am UTC](https://community.cartalk.com/t/bleeding-the-air-out-of-a-cooling-system/88571/2 "2015-01-05T06:24:43Z")

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Let us know what vehicle this is, mileage , history etc. Some have a bleed screw some do not. If you have a bleed screw it is straightforward. If not, Instead of using a screwdriver under the hose, with the engine cool, take the radiator cap off, park the car nose up, on a steep driveway or on ramps. Run it till it is warm and the bubbles should work their way out. Take a trip to the library and look through a Chiltons or Haynes manual to get a better description.

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**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\
**Post date:** [January 5, 2015, 6:27am UTC](https://community.cartalk.com/t/bleeding-the-air-out-of-a-cooling-system/88571/3 "2015-01-05T06:27:00Z")

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The upper radiator hose may be a little higher up than the radiator cap is all. Or on some vehicles there is no radiator cap by design. Suggest to follow SteveCBT’s ideas above, on most vehicles that should work.

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**Author:** ![SteveC76](https://avatars.discourse-cdn.com/v4/letter/s/958977/32.png) [@SteveC76](https://community.cartalk.com/u/SteveC76)\
**Post date:** [January 5, 2015, 6:31am UTC](https://community.cartalk.com/t/bleeding-the-air-out-of-a-cooling-system/88571/4 "2015-01-05T06:31:31Z")

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Some cars are difficult to bleed, I have had good results with vacuum bleeder. This might be costly for a home garage but a great time saver for a tech.

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**Author:** ![Rod-Knox](https://avatars.discourse-cdn.com/v4/letter/r/a183cd/32.png) [@Rod-Knox](https://community.cartalk.com/u/Rod-Knox)\
**Post date:** [January 5, 2015, 7:15am UTC](https://community.cartalk.com/t/bleeding-the-air-out-of-a-cooling-system/88571/5 "2015-01-05T07:15:38Z")

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If the radiator has a cap there’s no need to bleed it.

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**Author:** ![dodge330](https://avatars.discourse-cdn.com/v4/letter/d/ec9cab/32.png) [@dodge330](https://community.cartalk.com/u/dodge330)\
**Post date:** [January 5, 2015, 7:21am UTC](https://community.cartalk.com/t/bleeding-the-air-out-of-a-cooling-system/88571/6 "2015-01-05T07:21:38Z")

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no bleeder in system. Will try stevecbt’s advice. Thank’s

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**Author:** ![the\_same\_mountainbike](https://avatars.discourse-cdn.com/v4/letter/t/c89c15/32.png) [@the\_same\_mountainbike](https://community.cartalk.com/u/the_same_mountainbike)\
**Post date:** [January 5, 2015, 7:34am UTC](https://community.cartalk.com/t/bleeding-the-air-out-of-a-cooling-system/88571/7 "2015-01-05T07:34:17Z")

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The whole trick to bleeding a cooling system is to be sure that the vent for the air is higher than the highest point in the system, to ensure that there are no highpoints in the system that will entrap air, and to ensure that all cooling channels are opened (turn the heat ON). Systems in which a path exists that’s higher than the fill hole are designed with bleeders, because the air in that area will not go downhill, but will create a system block.

The trick of putting a screwdriver between the radiator port and the hose is simply to create a vent hole for the coolant for systems without pressure caps on the radiators. Some cars pressurize the reservoir. On systems with the pressure cap on the radiator, simply raise the front end (I use ramps) and remove the cap to purge the system. The air’s tendency to migrate to the highest point in the system will bring it to the fill hole.

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**Author:** ![dodge330](https://avatars.discourse-cdn.com/v4/letter/d/ec9cab/32.png) [@dodge330](https://community.cartalk.com/u/dodge330)\
**Post date:** [January 5, 2015, 8:44am UTC](https://community.cartalk.com/t/bleeding-the-air-out-of-a-cooling-system/88571/8 "2015-01-05T08:44:28Z")

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thank you all for your valuable advice. you guys are great

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**Author:** ![the\_same\_mountainbike](https://avatars.discourse-cdn.com/v4/letter/t/c89c15/32.png) [@the\_same\_mountainbike](https://community.cartalk.com/u/the_same_mountainbike)\
**Post date:** [January 5, 2015, 8:50am UTC](https://community.cartalk.com/t/bleeding-the-air-out-of-a-cooling-system/88571/9 "2015-01-05T08:50:15Z")

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Let us know how you make out. We do care.

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**Author:** ![dodge330](https://avatars.discourse-cdn.com/v4/letter/d/ec9cab/32.png) [@dodge330](https://community.cartalk.com/u/dodge330)\
**Post date:** [January 6, 2015, 7:47am UTC](https://community.cartalk.com/t/bleeding-the-air-out-of-a-cooling-system/88571/10 "2015-01-06T07:47:38Z")

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thank’s. Because we are scheduled for some bad weather this week, I will try to fix it this coming weekend. I will keep you guys updated.

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**Author:** ![meanjoe75fan](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/meanjoe75fan/32/552_2.png) [@meanjoe75fan](https://community.cartalk.com/u/meanjoe75fan)\
**Post date:** [January 6, 2015, 10:42am UTC](https://community.cartalk.com/t/bleeding-the-air-out-of-a-cooling-system/88571/11 "2015-01-06T10:42:09Z")

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It helps to park on the steepest hill possible to get the air to migrate to the front.
