View Full Version : Neat trick for getting the air out

04-23-2006, 11:41 AM
Since it was raining all weekend, I decided to flush the cooling system out in my 04 Cobra (been 2 years now and why not?).

First after the complete cooling system was drained, start by filling up the expansion tank with the bleed port open. I found that an old "water wetter" bottle worked great as a funel and it almost screws right into the bleed port. Once the fluid was full in the expansion tank, begin feeding water/coolant into the bleed port. when the expansion tank overflows, cap it off. Continue to add water/coolant into the bleed port until the funel fills up. Now comes the trick: squeeze all the hoses slowly and you will see bubbles flow out into the funel (water wetter - red line oil products, worked great since it is clear and made a good seal when screwed into the bleed port, do not screw it in too far just a little bit so the bottle will not break off in the bleed port). Continue to squeeze the coolant lines to work out any air (use variations of pressure on the hoses). Add more fluids if the level drops in the funel. Once there is no more bubbles comming out of the cooling system, loosen the cap on the expansion tank (expect fluids to flow out from the expansion tank) to drop the level of the fluid in the funel down to the top of the bleed port. tighten the cap to stop the overflow, remove the funel and then cap of the bleed port. Begin the heat/cool cycle as you normally would. The benefit is lack of coolant all over the motor as well as it made getting the air out much less of a pain. :thumbsup:

What makes it easier, if you have an aftermarket expansion tank like the Canton racing tank and a stant radiator cap with the pressure release lever on top of it. Loosening up the cap on the stock tank should do the same task.

04-24-2006, 10:39 AM
Good find, thanks for sharing I'll have to try that when I do mine.

04-24-2006, 01:34 PM
Thank You for the tip.