ZD331 - radiator drain plug - how to open

[GroundLoop]

Manual just says to open it. I tried to open the petcock gently with pliers and it was not moving. Noticed the nut on the end of the opening for the petcock. Tried taking that off with a fair amount of force and it would not move. Afraid to apply any more force. Can someone tell me how to open this.

 

[lugbolt]

I ain't never had to use pliers normally just grab it by hand and loosen (to the left) the valve. IF it's stuck, prepare to break it off. Then you just remove the remnant from the block and plug the hole with a NPT plug.

 

[imnukensc]

Try to turning it to the right.

 

[whitetiger]

Try to turning it to the right.

It turns to the LEFT (Counterclockwise) to open the valve and drain the coolant.

 

[skeets]

If you can get to the lower hose just pull that off,, makes a mess but you aint gona twist the petcock off and have to get a new radiator

 

[GroundLoop]

Welp....... Put PB Blaster on it a few times. Let it sit for 30 min. Went back and forth slowly with the pliers. Appeared to be making a little bit of progress and then snap. Put some PB Blaster on the nut. Used a 6 point socket and tried to get the nut off but it is not budging. Is that nut supposed to come off? Pretty sure it is.

Needed to change the coolant so I just took off the lower radiator hose and added Fleet Charge concentrate and distilled water.

What I do not understand is the previous owner bought it from a local dealer and had service done there too. I got the service records. Looks like they changed the coolant about four years ago. I guess maybe they just pulled off the lower radiator hose too.

I would like to get all the fluid out so I want to replace that drain. Maybe a call to Kubota is in order.

 

[woodman55]

I would replace it. If Kubota don't have one, I am sure a Napa type place will.

 

[lugbolt]

replace the drain valve assembly.

There are two different ones depending on the serial number of the ENGINE (not the tractor).

15841-73020 or 16871-73020

engine serial number is near the injection pump stamped into the block-usually directly below the pump. It will be something like D1005-8J045 or something like that, you're looking for the last of the characters post hyphen, in that example 8J045.

while you have the drain valve assembly out have a look-see at what the inside of the block looks like. Hopefully it's not rusty.

 

[lugbolt]

If you can get to the lower hose just pull that off,, makes a mess but you aint gona twist the petcock off and have to get a new radiator

drain valve is in the block on these.

 

[Dbozeman]

drain valve is in the block on these.

The drain Cock is broken off clean with block. Any ideas how to remove the rest of it 🥲

 

[Dbozeman]

The drain Cock is broken off clean with block. Any ideas how to remove the rest of it 🥲

 

[North Idaho Wolfman]

The drain Cock is broken off clean with block. Any ideas how to remove the rest of it 🥲

EZ out

 

[sitric]

Or drill and tap.

 

[woodman55]

If you have them, I would use a left hand drill bit.