Radiator replacement
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Radiator replacement
2008 f150 5.4l 3v. Bottom of radiator was leaking pretty bad so I have the new on ordered and waiting for it to arrive. The coolant was pretty nasty. Is there a way to flush the engine before the new radiator gets installed? I have the old one removed already. Just figured I'd get the old coolant out of the engine BEFORE installing the new radiator if possible. Thanks
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From: Ocean Springs MS
Read below even if you are going to use a flush additive
If I were you I would reinstall the old radiator, take out the thermostat, make sure the A/C controls are in Heat mode, flush (drain open to waste) with tap water for 20 minutes while occasionally reving engine. Wait at least 30 minutes between any heat up cycles. When tap water flush is complete, install new radiator, leave the thermostat out and fill with distilled water and flush (drain open to waste) with 4-6 gallons of distilled water, close drain. Top off radiator/overflow bottle with distilled water.
IMPORTANT - place a suitable container under drain, open drain and collect (Lowes concrete mixing pan works great) all of the water that will come out. Carefully measure the amount of distilled water that you drained out and verify it equals approximately 50% of your cooling systems capacity. The reason for this step will become clearer in the next few steps. Once you are satisfied that you have drained approximately 50% of your cooling systems capacity. Reinstall the thermostat while verifying the correct orientation and close the drain in preparation for filling. Make sure you do your best to get the air out and don't be surprised if you don't get all of your in antifreeze at first, the engine needs to get hot enough to open the thermostat before it can be filled completely. You now have cooling system that has about half of its capacity still in the block/radiator and this is distilled water. To get a 50/50 mix as your final concentration you need to add 100% concentrated antifreeze because the demineralized water portion is already in the block. I hope this makes sense, lets say your system capacity is 22 quarts and you were able to get 11 quarts out on the final drain leaving 11 quarts of distilled water in the block/radiator and this is all distilled water. 11 quarts of water in the block + 11 quarts of concentrated antifreeze = 22 quarts of 50/50 solution.
There is one more precaution in regards to weather. Its January and below freezing in most of the US so you can not leave pure water in your system, remember your block has about 11 quarts of the pure water which stays in the block and unless you heat the block it will freeze. Hopefully you have a heated garage.
If I were you I would reinstall the old radiator, take out the thermostat, make sure the A/C controls are in Heat mode, flush (drain open to waste) with tap water for 20 minutes while occasionally reving engine. Wait at least 30 minutes between any heat up cycles. When tap water flush is complete, install new radiator, leave the thermostat out and fill with distilled water and flush (drain open to waste) with 4-6 gallons of distilled water, close drain. Top off radiator/overflow bottle with distilled water.
IMPORTANT - place a suitable container under drain, open drain and collect (Lowes concrete mixing pan works great) all of the water that will come out. Carefully measure the amount of distilled water that you drained out and verify it equals approximately 50% of your cooling systems capacity. The reason for this step will become clearer in the next few steps. Once you are satisfied that you have drained approximately 50% of your cooling systems capacity. Reinstall the thermostat while verifying the correct orientation and close the drain in preparation for filling. Make sure you do your best to get the air out and don't be surprised if you don't get all of your in antifreeze at first, the engine needs to get hot enough to open the thermostat before it can be filled completely. You now have cooling system that has about half of its capacity still in the block/radiator and this is distilled water. To get a 50/50 mix as your final concentration you need to add 100% concentrated antifreeze because the demineralized water portion is already in the block. I hope this makes sense, lets say your system capacity is 22 quarts and you were able to get 11 quarts out on the final drain leaving 11 quarts of distilled water in the block/radiator and this is all distilled water. 11 quarts of water in the block + 11 quarts of concentrated antifreeze = 22 quarts of 50/50 solution.
There is one more precaution in regards to weather. Its January and below freezing in most of the US so you can not leave pure water in your system, remember your block has about 11 quarts of the pure water which stays in the block and unless you heat the block it will freeze. Hopefully you have a heated garage.
Last edited by Jimboy; Jan 18, 2025 at 08:10 PM.
