How to rmove and replace radiator drain petcock that is leaking?

Yes it will. There is a fibre washer or O-ring seal on the end of it. Yours has an O-ring. They are in a pretty hostile environment with near boiling water and pressure. It is a good opportunity to flush the system, and add new antifreeze. Clean the inside of the petcock hole with cloth on a wooden dowel to ensure they are no bit in there. They are only about $5 if you can find one for your vehicle.

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locate the radiator drain plug (normally bottom right or left of the radiator) unscrew and drain coolant (beware of hot coolant) once unscrewed fully, gently pull and turn the drain screw/petcock until removed.

the refit and refill coolant. its also a good time to flush and change coolant,

They Screw Out Like a Bolt And In The Same Way

disconnect , battery neg, term , so aunt Lulu dont try to drive dry car.
drain all coolant, (petcock valve , open)
remove fan wires, and all hoses. and attachments to rad.
unbolt rad, some have 4 bolts on sides, and some have only top
hold down screws. (looking works)
and if A/T tranny car , rmove the tranny cooler lines.
once its free of intanglements, you un clamp it from the body and
it comes out. (up)
why not log in to alldata.com and read the 25 steps.
log in and read.
its all there.

You don't. You never open the petcock on radiators with plastic tanks because the petcock always breaks. If it doesn't break, it'll leak when you close it. No pro ever uses the petcock. You loosen the lower radiator hose clamp and yank the lower radiator hose. You'll take a bath, but it'll all be drained in about 1.5 mins. Then reconnect. You'll actually drain far more coolant that way too.

you can try removing the plug and seeing if it is a gasket or an o-ring that seals it to the radiator. You should be able to find an o-ring or a gasket that will work at your local parts store. If replacing the o-ring or gasket does not work than the radiator will need to be replaced. We no longer drain radiators with the petcock for this reason.

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

if it has one that can be replaced than twist it counter clockwise untill it spins without coming out any more than just pull straight out.

There common to break off, you can pick up the replacement drain plug at NAPA and buy a stud retracter to remove the drain plug. if the plug is not leaking, Leave it alone and to drain the radiator, just disconnect the lower radiator hose on the opposite side of the radiator.

Good luck and hope this helps you on your project.

If you can remove it, you can replace it either with the correct size NPT pipe plug or another petcock. I generally use a plug with teflon tape on the threads and drain by removing the lower hose...It's faster and easier than using the drain!

Cooling System
Ensure that the engine is completely cool prior to starting this service.
1. Remove the recovery tank or radiator cap.
2. Raise and support the vehicle.
3. Place a drain pan of sufficient capacity under the radiator and open the petcock (drain) on the radiator.
è Plastic petcocks easily bind. Before opening a plastic radiator petcock, spray it with some penetrating lubricant.
4. Drain the cooling system completely.
5. Close the petcock.
6. Remove the drain pan.
7. Lower the vehicle.
8. Determine the capacity of the cooling system, then property refill the system with a 50/50 mixture of fresh coolant and distilled water.
9. Leave the recovery tank or radiator cap off to aid in bleeding the system.
10. Start the engine and allow it to idle until the thermostat opens (the upper radiator hose will become hot). The coolant level should go down, this is normal as the system bleeds the air pockets out of the system.
11. Refill the system with coolant to the proper level.
12. Turn the engine OFF and check for leaks.