Need help draining coolant
Thread Starter
Cruising
Joined: Nov 2009
Posts: 11
Likes: 0
From: Southampton Pa
Need help draining coolant
03 Z06 pulled the radiator plug today and only got 3 quarts of coolant out. What's going on? Everything I read says it's easy to get 2 gallons out. Any ideas out there what I'm doing wrong? Does the engine have to be hot for the thermostat to be open or something I'm missing? Only have 15K miles on it. Coolant is very clean.
Thread Starter
Cruising
Joined: Nov 2009
Posts: 11
Likes: 0
From: Southampton Pa
Thanks for the info. My thinking now is that the drain process involves siphoning and I may have interupted the process by starting and stopping the flow, thereby only draining the radiator. I'll try again next weekend, thanks. How much more did you get by pulling the bottom hose?
Safety Car
Joined: Jan 2001
Posts: 4,953
Likes: 490
From: Hilton NY
I took off the thermostat/ housing which is held on with two bolts then used a garden hose to flush out all the passages, this will clear out the block and heater core. When the water ran out clear from all passages the thermostat/ housing was replaced then the system was filled with tap water and antifreeze. My experience with deionized water is that it corrodes metal since it is hungry for ions.
Team Owner
Joined: May 2001
Posts: 36,836
Likes: 241
From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
I took off the thermostat/ housing which is held on with two bolts then used a garden hose to flush out all the passages, this will clear out the block and heater core. When the water ran out clear from all passages the thermostat/ housing was replaced then the system was filled with tap water and antifreeze. My experience with deionized water is that it corrodes metal since it is hungry for ions.
Personally I like prefer to use distilled water.
Melting Slicks
Joined: Jul 2006
Posts: 2,332
Likes: 31
From: Silver Spring MD
I drain and pull the overflow tank and add water with a hose
First drain the radiaror. Remove expension tank and use one of the hose connections to flush with water from garden hose while running engine. Let drain and repeat. Let thermostat open to ensure flushing whole system. After about 3 cycles and when coolant runs clear let it drain one last time. Then add full strength Dexcool till the radiator is full. Run engine and heater on full heat to get the air out of the system. Add more full strength Dexcool to tank and check level for the next 2 weeks.
Tech Contributor
Joined: Jan 2007
Posts: 19,115
Likes: 1,038
From: Dyer, IN
First drain the radiaror. Remove expension tank and use one of the hose connections to flush with water from garden hose while running engine. Let drain and repeat. Let thermostat open to ensure flushing whole system. After about 3 cycles and when coolant runs clear let it drain one last time. Then add full strength Dexcool till the radiator is full. Run engine and heater on full heat to get the air out of the system. Add more full strength Dexcool to tank and check level for the next 2 weeks.
Team Owner
Joined: May 2001
Posts: 36,836
Likes: 241
From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
First drain the radiaror. Remove expension tank and use one of the hose connections to flush with water from garden hose while running engine. Let drain and repeat. Let thermostat open to ensure flushing whole system. After about 3 cycles and when coolant runs clear let it drain one last time. Then add full strength Dexcool till the radiator is full. Run engine and heater on full heat to get the air out of the system. Add more full strength Dexcool to tank and check level for the next 2 weeks.
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Tech Contributor
Joined: Jan 2007
Posts: 19,115
Likes: 1,038
From: Dyer, IN
....and if you look in the 97-01 service manual, is states "clean drinkable water"......and changes to "deionized water" in the 02-04 service manual.
