Radiator Flush: How To??
05-13-2006, 09:13 PM
#1
Burning Brakes
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Radiator Flush: How To??
I have yet to have my radiator/anti-freeze flushed.
How would I go
about doing this myself? Or should this be left up to the local pros?
How would I goabout doing this myself? Or should this be left up to the local pros?
05-14-2006, 02:04 AM
#3
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St. Jude '03-'04-'05-'06-'07
Depends on what you want: Flush or Complete Power Flush: Right after i got my 87, replaced upper/lower rad hoses and took in in to have a complete Power Flush and radiator cleaning... Haven't had any issues... but since have replaced rad with DeWitts Alum...
05-14-2006, 10:26 AM
#4
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Drain as much of the old coolant out as you can, then refill with clean water. Add some dishwasher detergent (not soap) and run the car for about 1/2 hour. Flush all of the old stuff out (I usually open the petcock on the radiator and stick a hose in the upper tank with the inflow rate equal to the out flow) Run the car until clean water is coming out of the radiator, then turn off the engine, shut off the hose and let as much drain out as possible again. Then refill with fresh anti freeze. Remember to burp the system and also remember that the LT1 cooling system holds about 16 quarts.
05-14-2006, 12:05 PM
#5
Team Owner
The procedure in the service manual calls for removing the knock sensors at the bottom of the block to drain the old coolant from the block. The manual also states to not use any chemical cooling system cleaners unless there is evidence of corrosion. These caustic cleaners may ruin the bond between the plastic radiator tanks and the aluminum tubes.
Guess I have never heard of using diswasher detergent in cleaning out a cooling system
Typical detergents like this contain citric acid and I would be concerned about potential for damage to sensors, rubber hoses and the aluminum in the radiator.
The manual says to flush the system, remove the knock sensors and drain the radiator. Refill with clean water, run the engine for a few minutes, drain and refill again. The knock sensors hide behind a metal heat shield which is plainly visible in the center of the block above the oiul pan rail. You need a 22mm socket to remove the sensors. Expect lots of coolant to drain! Also remove the plastic overflow tank, drain and clean it out. No need to reinstall yet.
This would be a good time to change the upper and lower radiator hoses.
Open the bleed valve on the thermostat housing and on the driver's side of the throttle body. With all of the old water out, pour in 2 gallons of antifreeze. IIRC, your 94 used the green (ethlyene glycol) coolant.
Get 3 gallons of distilled water from the local grocery store (About a buck a gallon). Add the distilled water until coolant comes out the bleed valves steadily the close both valves. NOTE: keep the coolant away from the Opti!! Use old towels or fashion a drain tray from aluminum foil. Soak the Opti and many hundreds of dollars later, your car will run again!
Continuing filling with the water until it reaches the base of the filler neck in the expansion tank. Start the engine and let it idle; keep an eye on the digital temp dispaly. When the thermostat opens, refill the expansion tank back to the base of the neck. If the temps climb to 220-230, shut the motor down and let it cool and re-start.
Once the level stays constant, shut the motor off, re-install the overflow tank and replace the radiator cap. Make up a 50-50 mix of antifreeze and the distilled watrer and fill the overflow tank to the cold level.
The service manual also states to not perform any full-throttle acceleration until the engine has gone thru 3 complete cycles of cold to operating temp and back to cold. If there are any air pockets left, full-throttle operation may cause excess pressure in the system. Cycling the coolant temp allows air to eventually work it's way out.
Guess I have never heard of using diswasher detergent in cleaning out a cooling system
Typical detergents like this contain citric acid and I would be concerned about potential for damage to sensors, rubber hoses and the aluminum in the radiator.The manual says to flush the system, remove the knock sensors and drain the radiator. Refill with clean water, run the engine for a few minutes, drain and refill again. The knock sensors hide behind a metal heat shield which is plainly visible in the center of the block above the oiul pan rail. You need a 22mm socket to remove the sensors. Expect lots of coolant to drain! Also remove the plastic overflow tank, drain and clean it out. No need to reinstall yet.
This would be a good time to change the upper and lower radiator hoses.
Open the bleed valve on the thermostat housing and on the driver's side of the throttle body. With all of the old water out, pour in 2 gallons of antifreeze. IIRC, your 94 used the green (ethlyene glycol) coolant.
Get 3 gallons of distilled water from the local grocery store (About a buck a gallon). Add the distilled water until coolant comes out the bleed valves steadily the close both valves. NOTE: keep the coolant away from the Opti!! Use old towels or fashion a drain tray from aluminum foil. Soak the Opti and many hundreds of dollars later, your car will run again!
Continuing filling with the water until it reaches the base of the filler neck in the expansion tank. Start the engine and let it idle; keep an eye on the digital temp dispaly. When the thermostat opens, refill the expansion tank back to the base of the neck. If the temps climb to 220-230, shut the motor down and let it cool and re-start.
Once the level stays constant, shut the motor off, re-install the overflow tank and replace the radiator cap. Make up a 50-50 mix of antifreeze and the distilled watrer and fill the overflow tank to the cold level.
The service manual also states to not perform any full-throttle acceleration until the engine has gone thru 3 complete cycles of cold to operating temp and back to cold. If there are any air pockets left, full-throttle operation may cause excess pressure in the system. Cycling the coolant temp allows air to eventually work it's way out.
05-14-2006, 12:42 PM
#6
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Originally Posted by jrzvette
Drain as much of the old coolant out as you can, then refill with clean water. Add some dishwasher detergent (not soap) and run the car for about 1/2 hour. Flush all of the old stuff out (I usually open the petcock on the radiator and stick a hose in the upper tank with the inflow rate equal to the out flow) Run the car until clean water is coming out of the radiator, then turn off the engine, shut off the hose and let as much drain out as possible again. Then refill with fresh anti freeze. Remember to burp the system and also remember that the LT1 cooling system holds about 16 quarts.
anti-freeze fill up? Thanks
