Sticking radiator drain cock 2002 Chevy malibu

I would like to drain the radiator on my 2002 Chevy malibu LS. I used a mm allen wrench and cracked open a white plastic plug about an eighth of an inch and it would not move any further and all I got was a dribble from the radiator.

Is it possible that I can force the plug open more with out damaging it and is this common for this type of drain plug to be quite hard to turn?

hotpipes

Use caution with the drain valve on the radiator. If you've moved it a bit gently tighten it up and leave it. These valves often become stuck in older rads, yet are fragile and easy to break. Forcing it will break it. So, if it does not loosen easily, use an alternative to drain a radiator.

To drain a side-tank rad, usually I can siphon the old coolant out by removing the upper radiator hose and insert a thin, plastic tube down the tank, then siphon out into a container. Once that's done, I remove the lower radiator hose, and, using a big splash pan or bucket, catch whatevers left coming out.

The drain valve not only has to be turned, it has to be pulled outward....there is a pin on the valve that slides in a groove.....as it slides in the groove, it moves outward......sometimes it gets stuck.....uses the allen in a pivoting rotational manner so that you rotate and pull at the same time, and then the valve will open completely,,,,

Thank you Tech ll

This sound like what I need to do. Like you say the plug dose come out when I turn it about an eighth of a turn. Do I need to help it come out more with a common screw driver as I turn it with the allen wrench?

hotpipes

When I stick my allen socket in, as I rotate it, I pivot it downward.....then as I rotate, I pull outward at the same time......have to be careful prying with a screwdriver, because the housing that the valve goes into is plastic, can break....if it rotates and stops, maybe a pair of mini vice grips can grab the outer edge, and you can rotate/pull with the vice grips....when that opens up, it will gush out....be prepared....

When I stick my allen socket in, as I rotate it, I pivot it downward.....then as I rotate, I pull outward at the same time......have to be careful prying with a screwdriver, because the housing that the valve goes into is plastic, can break....if it rotates and stops, maybe a pair of mini vice grips can grab the outer edge, and you can rotate/pull with the vice grips....when that opens up, it will gush out....be prepared....

Thank's again I didn't need the screw driver or the vice grips. It opened and drained with out any more coaxing.
hotpipes

I always spray with penetrating oil , PB or WD, spray again when tightened.