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How do you bleed air out of the coolant system after draining

47K views 12 replies 9 participants last post by  RJR88 
#1 ·
and refilling the radiator?
Thanks!
 
#2 ·
You buy a new autozone cap :D

actually there is a bleed plug on the t-stat housing. See your owners manual.

Jim
 
#5 · (Edited)
I filled mine until coolant came out of the bleed port on top of the front thermostat housing. After I replaced the plug, I added fluid until the tank was about 3/4's full. I started the engine and the book says to cycle the rpm's up and down several times to purge the air out and draw fluid in. The cap should be loose during cycling. After cycling for a couple of minutes, I added more coolant back to the full mark and drove around. Next morning I added more coolant back to the full mark.

In the LLY section there is a lot of info on the caps / cooling system etc. Many of the LLY guys are having heating problem and have done abunch of research - good reading. There are a number of threads going on the issue

you can search the LLY forum for JJ + flush and see threads like

"JJ's patented flush method" or "Degas De-mistified" plus several more


On Edit: The book says to Idle the engine for 1 minute then cycle the RPMs from idle to 3000 in 30 sec intervals until you reach 210* F - This is with the cap loose so you don't build pressure. Remove the Cap ( CAREFULLY ) refill and repeat.....FWIW
 
#6 · (Edited)
I have found that correctly purging air, is a laborious headache!

You can use the bleed screw, that will fill the motor, in bypass. The radiator is more difficult, since the second a T-stat cracks, it closes when cold coolant comes into the block, then takes forever to heat up. So the driveway method is not effective. Will fill over a few thermal cycles, topping the coolant each morning, if the cap is working correctly.
 
#7 ·
Not a whole lot of anything special required. What mightyvh said about sums it up. The air will purge to the bleeder when filling and from there, do the cycle thing, and drive it to operating temp to open stats and enhance flow through the surge tank.

No drilling required OR recommended...
 
#8 ·
Not a whole lot of anything special required. What mightyvh said about sums it up. The air will purge to the bleeder when filling and from there, do the cycle thing, and drive it to operating temp to open stats and enhance flow through the surge tank.

No drilling required OR recommended...
That's the way I did it. I have'nt had a problem so far.
 
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