Coolant
Pro
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From: Portland Oregon
Burning Brakes
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From: Native Californian CALIFORNIA
Army
Race Director
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Specifically no, but it depends. If converting from an IAT to OAT the system should be completely drained and thoroughly flushed. It's okay to change from IAT to HOAT without flushing, but one should still drain all the old antifreeze, and the block holds at least 4 quarts. Not draining the block would be like draining out only 3/4 of the old oil for an oil change job.
A through water flush is always optional.
BTW over the years whatever coolant changed were done it's likely that the block drain plugs were never removed. In this case nothing may drain out when they are removed, so you have to dig out all the debris with a sharp tool. If this is the case I recommend a thorough system flush.
Duke
A through water flush is always optional.
BTW over the years whatever coolant changed were done it's likely that the block drain plugs were never removed. In this case nothing may drain out when they are removed, so you have to dig out all the debris with a sharp tool. If this is the case I recommend a thorough system flush.
Duke
