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Coolant Flush procedure

I did a DIY coolant flush this weekend. I pulled the front bumper and bellypan, took off the cap on the expansion bottle, and opened the petcock on the bottom passenger side of the radiator. I let all the coolant drain, refilled with distilled water and let the car idle. I flushed about 4.5 gallons out of it. Replaced with the new yellow motorcraft coolant, distilled water, and a bottle of water wetter. Is there an easier way? On my 05 F150 I would always just pop the lower radiator hose off because it doesn't have a drain valve on the radiator.
That's the only way without special flush machines that many shops have. You never get all the coolant out as well because some always stays in the block so if your doing it as maintenance it's all good but if you had a failure and need to get all the coolant out I suggest getting it power flushed.
Exp. Type
Exp. Level
5-10 Years
Philly Metro Area
This is what I was told:

There is a plug just to the rear of the oil filter adapter. It is a 3/4" NPT plug that needs a 9/16" long shaft hex driver to remove. It will drain most of the block but a wet dry shop vac will pull it all out. Use an air lift to put the completed engine under vacuum to draw in the new coolant. It will prevent any air pockets left behind in the top of the heads.


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