Answer Guide

Raj

Knowing the exact procedure and proper details is always necessary while doing this task.

The details are as follows :-------

The recovery tank, and it's cap, is pressurized only if the coolant is hot, just like if the cap was on the radiator. (Or it should be unless you've got a blown headgasket.)

There should be a drain on the radiator but it's probably a plug and not a petcock. There should be drains on the block somewhere but they're probably hard to get to (so personally, I won't bother with them when my time comes this summer). Many people pull the lower radiator hose for a very quick drain, with coolant soaking pretty much everything in the area, including themselves.

Refilling is through the recovery tank.

Regardless of how you drain, when refilling it is very important to open the bleeder on top of the front thermostat housing to initially get as much air out of the system as possible. Even so, it may take a few warmup cycles to get all the air out (burping), while keeping the coolant level set in the recovery tank (but don't overfill, either). It might help burp itself just sitting over night. (A few have claimed success not using the bleeder; others had big problems possibly caused by air pockets left in the system.).

Just start refilling through the recovery tank. The coolant will flow right into the radiator. On mine, we loosened the burp screw on the T-stat housing, and we filled until fluid came out at the screw. Tightened the screw up, and filled the tank to proper height.

Come back the next day and check fluid level, refill to proper height if necessary.

Here is the detail with steps:----------

: 25qt capacity=3 gal of coolant and 3 gal of distilled H20

Remove radiator drain plug located on p.s. lower corner.

Remove de-gas tank cap...watch your feet.

Remove thermostat housing and remove thermostats. Replace thermostat housing.

Disconnect the upper radiator hose and replace the radiator drain plug.

Back-flush system by placing garden hose into the upper radiator hose.

Remove the radiator drain plug, drain, and replace.

Remove thermostat housing.

Fill system with 3 gal of Dex-cool/comparable coolant through the de-gas tank. Continue to fill system with distilled water until it is visible at thermostat housing.

Replace thermostats, but remove bleeder screw at front of housing.

Connect the upper radiator hose.

Continue to fill system until COOLANT is visible from bleeder hole (this would purge most of the tap water used in the flush).

Replace bleeder screw and top off tank. Replace cap.

Drive truck until thermostats open, and top off tank again.

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I buy a Prestone Flush kit that has the tee that goes into a heater hose. I'm assuming (1) that they still makes the tee kits, and (2) there's an appropriate place to T it into a heater hose.

1. Take off the recovery tank cap and open the radiator drain and capture as much of the coolant as possible for proper disposal.

2. Install the T and hook up a garden hose with threaded sprayer control to the tee. Start gently injecting water (not sure about the flow rate because of the small drain routes from the radiator) until everything runs clear.

3. I'm assuming the system is clean. If not, then close the drain and run a chemical quick flush in it, then drain/fill several times to get all of that out.

4. When done flushing, the only problem is there's probably about 3 gallons of tap water in it, and Southern California has very hard water. I'm thinking of topping with 3 gallons distilled, run that, drain, and repeat again. That leaves dilluted tap water (25%?) but at least it hasn't got so much "hardness".

5. Final fill is with pure Dexcool, including the reserve tank, assuming it's still got that 3 gallons of water. All fills are done with the bleeder open. On the final fill, both the bleeder and the T are left open (remove hose nossle and Prestone check valve adapter). Capped the T and close the bleeder when coolant starts coming out (i.e., let any water that comes out those exits drain out).

A side benefit of using the T kit is that while flushing, it's pretty quick to fill up the system with water (as opposed to using the reserve tank).

For more details read this

Pour the cooling system flush in the radiator. If there is not enough room then the radiator has to be drained of some coolant to make room. Start the Silverado and allow it to reach operating temperature. Shut the engine off and give it about 15 minutes to cool down.Place the catch pan under the lower radiator hose and remove the spring clamp with the hose removal tool or the pliers. Slowly remove the hose so that it does not dump all the coolant at once and make a mess. Let it drain for a few moments after the large part of it has come out. Replace the hose and the clamp. Remove the top clamp and hose at the radiator.Fill the radiator with water and start the engine, leaving the top radiator hose off. Flush the system out to get rid of all the contaminants left after the engine was flushed. It will take a few minutes for the thermostat to open. Once water starts coming out of the top hose, it has opened. Just keep adding water for about five minutes and then shut the engine off.Remove the bottom radiator hose once again and allow the water to drain out. Hook up both radiator hoses. Pour two gallons of coolant into the radiator. Top it off with water.

This should help.

Thanks.

CAR PROBLEMS