Hey guy's can someone give me a sure fire way to purge all of the air out of my cooling system. I just replaced my thermostat, filled the block up at the thermostat housing, dropped in a new thermostat, and filled the radiator from the upper hose. I thought this method would keep the airbuild up in the system to a minimum. But low and behold when I start my truck up I can hear gurgling or what sounds like rushing water, like ther is air traped in the heater hoses or such.

Does anyone have any type of method they use to get out all of the air? Or should I take it in and have a proffesional do it?

Thanks,
Brad

 

I always fill it by the radiator cap but leave it a few inches low. Then start the engine, turn the heater on high and let it warm up fully. Once the thermostat opens fully and I get good flow into the radiator, I start adding coolant until full. Install the cap and then shut off the engine. Be sure that there is fluid in the reservoir so that it will not suck in air as the engine cools.

 

You can buy a kit that includes a tall funnel that attaches to and seals the radiator cap opening. Then you need to find an incline so the funnel is higher than any point in the engine where coolant flows, including the heater core. Next, you fill the funnel to about 2 inches from top and run the truck with the heater on high as TOY283 suggests. Once the thermostat opens, the coolant will start to circulate and you should be able to watch air bubbles 'burp' their way through the funnel.

I usually run this process for about 30 minutes or until you don't see any more air bubbles escaping. Then you need to extract the extra coolant from the funnel with a turkey baster or similar. Take the funnel off and make sure the radiator is topped off and replace the radiator cap. Then make sure your overflow container is filled to halfway between the minimum and maximum markings, and you should be set.

Good luck.