Proper way to flush
wipeout
03-07-2005, 09:46 AM
I was wondering if anyone could tell me the best way to flush Dex-cool out of my cooling system. I have 3 to do, an /03 Impala, a 2000 Montana and a /98 chev 1/2 ton 4.3.
Thanks.
Thanks.
curtis73
03-07-2005, 01:19 PM
Here's the technique I used.
Pull all the plugs in the block, (should be just one per side) drain the radiator, maybe pull the heater hoses. I bought a big black utility pan at Home Depot. Its a plastic disposable cement tray over in the cement aisle. Its about 2' x 3' x 8" deep. Great for catching the coolant. Sure beats using a bucket :). Pull the thermostat out and replace the neck. Now, with everything re-attached and plugged except the heater supply hose (the one that sends coolant to the heater) you can start to flush with a gardent hose. Hook up a spare piece of heater hose to wherever you just left empty; the supply nipple for the heater. For some that's on the water pump, some on the manifold, and some its on the head. Set your garden hose to a low flow and hold it up to that spare piece of hose and put the heater hose in a bucket or the tray. This will completely backflush the system and you'll know that water is flushing everywhere since you're using the highest point on the car as the drain. Water won't come out the heater until the engine, radiator, and heater core have filled up. You can ensure that by leaving some hoses and mabye the radiator cap loose. Yours probably have the pressure cap located on the expansion tank, right? This process should flush that tank, but you may have to pull the hose off the bottom to speed that up.
Most drivers will then drain and refill with the coolant of their choice after the water runs clear. That is a fine idea, but I used the opportunity to run a can of radiator flush through it. I put the heater hose back on so its all sealed up and put Prestone radiator flush in the expansion tank. I drove it for a day (follow the directions on your bottle) and then drained and refilled. That not only cleaned junk out, but also really gave it a chance to work the Dex out of the corners.
Pull all the plugs in the block, (should be just one per side) drain the radiator, maybe pull the heater hoses. I bought a big black utility pan at Home Depot. Its a plastic disposable cement tray over in the cement aisle. Its about 2' x 3' x 8" deep. Great for catching the coolant. Sure beats using a bucket :). Pull the thermostat out and replace the neck. Now, with everything re-attached and plugged except the heater supply hose (the one that sends coolant to the heater) you can start to flush with a gardent hose. Hook up a spare piece of heater hose to wherever you just left empty; the supply nipple for the heater. For some that's on the water pump, some on the manifold, and some its on the head. Set your garden hose to a low flow and hold it up to that spare piece of hose and put the heater hose in a bucket or the tray. This will completely backflush the system and you'll know that water is flushing everywhere since you're using the highest point on the car as the drain. Water won't come out the heater until the engine, radiator, and heater core have filled up. You can ensure that by leaving some hoses and mabye the radiator cap loose. Yours probably have the pressure cap located on the expansion tank, right? This process should flush that tank, but you may have to pull the hose off the bottom to speed that up.
Most drivers will then drain and refill with the coolant of their choice after the water runs clear. That is a fine idea, but I used the opportunity to run a can of radiator flush through it. I put the heater hose back on so its all sealed up and put Prestone radiator flush in the expansion tank. I drove it for a day (follow the directions on your bottle) and then drained and refilled. That not only cleaned junk out, but also really gave it a chance to work the Dex out of the corners.
wipeout
03-07-2005, 04:32 PM
Thanks Curtis.
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