How do you bleed the air out of a LT1 cooling system?
04-20-2009, 12:36 AM
#2
I never followed the recommended procedure, just filled the expansion tankr, ran the engine till hot, fed the reservoir till it was full, then overfilled the remote reservoir and ran it through some off-on cycles. In my experience, it fixes itself up fine. I tried all that air screw bleeding bunko and only got frustrated. They make it sound like rocket science but the system fixes itself if you give it time and enough coolant in the remote. Just watch the temp gauges - mine never went overboard. If the had, I would have shut off the motor.
04-20-2009, 08:00 AM
#3
Le Mans Master
I never followed the recommended procedure, just filled the expansion tankr, ran the engine till hot, fed the reservoir till it was full, then overfilled the remote reservoir and ran it through some off-on cycles. In my experience, it fixes itself up fine. I tried all that air screw bleeding bunko and only got frustrated. They make it sound like rocket science but the system fixes itself if you give it time and enough coolant in the remote. Just watch the temp gauges - mine never went overboard. If the had, I would have shut off the motor.
The above works for me. (for over five years) You have to be able to use both hands at the same time. (right hand keeping revs at1500 and left hand adding coolant to the top)
04-20-2009, 07:25 PM
#5
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04-20-2009, 09:39 PM
#6
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There are 4 tricks.
1. SLOWLY add the coolant to the black-pressure-tank and periodically squeeze and release the lower radiator hose to help move the fluid around the engine and radiator.
2. Don't overfill the black pressure tank (keep the fluid level 2+ inches below the 'radiator cap' recess).
3. Put the 'radiator cap' on within 2-3 minutes of starting the car.
4. fast idle (1500-2000 rpms) for 3-5 minutes or drive the car to help move any air to the black pressure tank (the black pressure tank's purpose is to provide an air pocket for pressure and to provide a high point to 'scavenge' air from the system).
If you wish, after some pressure has built within the system, with lots of paper towels underneath, slightly and quickly open the bleeder screws to let any air out (depending on year, there could be 2 -- one over thermostat housing, one under the throttle-body accessed from the driver side just above the radiator upper hose tee'd hose).
remember, do not drive the car hard for at least 3 complete heat-up/cool-down cycles and monitor the overflow tank (by the bumper) to keep it full.
1. SLOWLY add the coolant to the black-pressure-tank and periodically squeeze and release the lower radiator hose to help move the fluid around the engine and radiator.
2. Don't overfill the black pressure tank (keep the fluid level 2+ inches below the 'radiator cap' recess).
3. Put the 'radiator cap' on within 2-3 minutes of starting the car.
4. fast idle (1500-2000 rpms) for 3-5 minutes or drive the car to help move any air to the black pressure tank (the black pressure tank's purpose is to provide an air pocket for pressure and to provide a high point to 'scavenge' air from the system).
If you wish, after some pressure has built within the system, with lots of paper towels underneath, slightly and quickly open the bleeder screws to let any air out (depending on year, there could be 2 -- one over thermostat housing, one under the throttle-body accessed from the driver side just above the radiator upper hose tee'd hose).
remember, do not drive the car hard for at least 3 complete heat-up/cool-down cycles and monitor the overflow tank (by the bumper) to keep it full.
