How to fix a leaking Cummins radiator drain plug.

This is a super simple fix.  Anyone with some needle nose pliers and a flat screwdriver can do it!

First thing you need to do is locate it, which, if you found this article, you likely have already done.  If not, it's on the bottom, drivers side of the radiator.

Now you'll want to drain the radiator of all the coolant, If your fancy automatic drain valve didn't already.

You can drain it into a couple jugs so you can reuse it (prepare for up to 5 gallons).  I would suggest getting used to using a syphon hose out of the fill cap.  The plastic drain valves are a joke. 

OK Now that you're ready to take it apart.  Take your needle nose pliers and open the drain valve just shy of 180*.  fully open is about 225*.  Now wiggle it about and pull it straight out, you may need to use your screwdriver to help pry it out a little while you wiggle.

OK, now it's out!  you'll see an O-Ring, it is likely nicked or cut.  Now you got a few options, you can buy a hole new valve (NAPA P#605-1372, AutoZone P#61134 ).  Or you can just pull an O-ring out of a kit that looks about right and hope it doesn't leak... you can guess which I did!  Fingers crossed!

Like with any O-Ring, it's a good idea to put a little lube on to help it go in.  I use petroleum jelly, but I'm sure soap would work aswell.

Not to sound like a haynes repair manual, but installation really is just opposite as removal.  Just make sure the "handle" on the plug is facing straight up and down.  Then press into place, refill the radiator, and you're good to go!

One leak free radiator drain valve coming right up!

If you have any further questions, please feel welcome to ask them on the Mopar1973Man Forum.