Originally Posted By: TmanP
I posted a couple days ago about flushing my coolant. One follow up question- when watching Youtube videos, people flush with distilled water (like I'm going to do) several times, then add 50/50. I'm confused, as even ChrisFix did it this way. It seems that you would have very weak coolant, with about 75% water. Am I missing something? Should I flush till it's clean then count the distilled water in the engine as half of my mix and add straight coolant? (My radiator holds ~6 quarts, total capacity is 12)
Thanks.
Don't pay any attention to that video he flubbed the job, as you say he ended up with a weak mixture.
With these 3800 engines flushing them properly is an easy job, I do them all the time, this is how I do them.
1) Loosen the bleeder valve on the thermostat housing to insure it isn't seized in place.
2) Drain the radiator.
3) remove the overflow tank to empty it and clean it.
4) Remove the following. The lower radiator hose from the water pump, the upper radiator hose from the thermostat housing, the thermostat housing and thermostat, the 2 heater hoses from behind the alternator on top.
5) With a garden hose (no pressure) flush the block from the intake manifolds thermostat hole until the water runs crystal clear out of the water pump, do the same for the radiator from the upper hose and heater hoses. Now the system has only clean water in it, close the radiator drain for now when empty.
6) Fill the radiator through the upper hose with a gallon of distilled water and open the drain, allow it to empty and close it. Fill 2 gallons fo distilled water through the thermostat hole until it flows out f the water pump connection, reconnect the hose.
Using a funnel fill a gallon of distilled water through the heater core and reconnect the hoses.
7) Now the heater and lower hose are connected and the radiator drain closes with the thermostat still removed fill one gallon of straight dexcool into the upper hose, water will flow out of the thermostat hole, the straight coolant will initially displace the water not mix with it.
8) Replace the overflow tank empty.
9) Replace the thermostat and housing and connect the hose, it might be a good time to replace the thermostat, use only OE from the dealer, make sure it has a jiggle valve if the old one did. Leave the previously loosened bleeder loose and slowly fill the radiator very slowly with a 50/50 dexcool mix until it flows freely from the bleeder then close the bleeder and fill to about 3 inches from the top of the radiator or the transmission cooler lines in the radiator,leave the cap off.
10) Fill the overflow with a 50/50 mix to the full mark and start the engine, turn the heat to full and let it idle. When you feel the top radiator hose getting hot and the heater blowing warm air turn off the engine.
Let it settle a few minutes then fill the radiator to the top and replace the cap, restart the engine and let it get to operating temperature then shut it off and let it cool down then check the level in the radiator and overflow.
