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Questions: coolant system flush

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Old Apr 5, 2009 | 11:35 PM
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Default Questions: coolant system flush

I am planning to flush the system and I want to drain the block as well as the radiator; will I experience leakage once I remove the drain plugs from the block? Any recommendations if leakage is a common occurrance? What problems can I expect from this coolant flush, other than a wet garage floor.
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Old Apr 6, 2009 | 08:38 AM
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I was going to do the same thing (drain the block) but other said it was a WITA and to flush the system 2 or 3 times with distilled water. So thats what I did. Only problem I had was the drain peacock had to be pulled back with needle nose after loosening before coolant would drain out.
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Old Apr 6, 2009 | 11:57 AM
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If you have not pushed the coolant to the 5 year limit and the coolant still looks clean, I would just drain the 8 quarts you can get out by just draining the radiator, and refill with 50/50 mix.
I never let Dexcool go over 2-3 years, so I just refresh what I can without flushing the whole system.
If you flush the system and leave 4 quarts of water in the block, you will need to add at least 6 quarts of pure Dexcool to get back to a 50/50 mix.

I would avoid removing the drain plugs on the block.
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Old Apr 6, 2009 | 07:08 PM
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The flush procedure in the service manual works very well as I just did this a couple weeks ago. I would certainly avoid removing the drain plugs.
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Old Apr 7, 2009 | 11:45 AM
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If you have the car level and heater on when draining, you can drain out all but about 2 quarts. If it is clean (nice pink) and not muddy brown, you do not have to flush, according to shop manual.

I have just drained my 1998 twice for time (only 119,000 miles total), never flushed.
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Old Apr 7, 2009 | 02:29 PM
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I just hook up the garden hose and drain and refill a couple of times until the drained fluid is clear water. Then I refill with the proper amount of DexCool and top off with water. You don't need distilled water just clear drinking water.

Bill
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