Head gasket issues D 902 E3

[edigert]

I have a zd-323 mower that i am rebuilding due to accidentally opening the coolant drain on the side of the motor while changing fuel filters resulting in overheating. I have fixed that drain with a plug btw.

Block was honed and cylinders within spec. I had the head checked as well for flatness and it was with in spec.

I am having issues with leaking headgasket now. It is leaking a tad bit of oil out around the oil pipe going into the head. I suspect I put the o-ring in the wrong place, but have tried under and on top of the headgasket with no success. The wsm i have says to put gasket on then o-ring, when re assemblying. I tried that and it leaked. Called a kubota mechanic at a dealership and he said to put the oil oring on the pipe then headgasket and it leaked. Another said not to use the oring tried it and it leaked water out in the same area before i even started it......... anybody have some advice for me here?

I have a new headgasket and oring ordered as some say its a one and done deal....but I need to know where the oil o-ring goes. I know the procedure, specs and pattern on tightening the head bolts and have it committed to memory.

 

[D2Cat]

Not familiar with your specific engine, but generally you will find the oil port where the O-ring goes at the back of the engine, by the firewall, on the left side as you set on the tractor seat.

If that seal gets slid out of position (or not there at all), you have a problem!

 

[edigert]

Thanks for your reply. I know where the oil port is I just need to know where where to put the o-ring. On top of the gasket or under the gasket. I cant remember where it was when I tore the motor down.

 

[North Idaho Wolfman]

What is the P/N of the gasket you are getting or got?
Did you have the head leak tested? As most Kubota engines will crack the head when they overheat.

The parts list does not show that engine taking an O-ring.
If the gasket does not have a large enough hole for the O-ring to pass through it then it normally doesn't normally take an O-ring, as the seal will be in the gasket.
A picture of the Gasket and the Block with pin pipe and we should be able to give you a 100% answer what to do.

Just as a note:
You cannot reuse the gasket once it's been torqued down, the crush surfaces will not match up and it will leak water like you noted.
You will need to get a new gasket if you want to make use it's not going to just leak on reassembly.

 

[200mph]

1. Are you certain an o-ring is called for? Don't see it in the cylinder head drawing. (See 1st attachment)

2. Can the head bolts be reused multiple times or are they torque to yield?



Added in Edit:

Might want to double check the WSM. I couldn't find a WSM manual online, but found one for the ZD326, so I'm hoping it is at least along the same design. On this particular head gasket the o-ring is NOT used. It's even in bold font in the manual. See 2nd attachment.

Please note I'm only suggesting to verify with correct WSM for the ZD323.

 

[North Idaho Wolfman]

1. Are you certain an o-ring is called for? Don't see it in the cylinder head drawing. (See 1st attachment)

2. Can the head bolts be reused multiple times or are they torque to yield?



Added in Edit:

Might want to double check the WSM. I couldn't find a WSM manual online, but found one for the ZD326, so I'm hoping it is at least along the same design. On this particular head gasket the o-ring is NOT used. It's even in bold font in the manual. See 2nd attachment.

Please note I'm only suggesting to verify with correct WSM for the ZD323.

#1 No O-ring is used
#2 Kubota head bolts are not torque to yield, they can be reused.

 

[edigert]

Thank you for all the useful information.

The only reason I got a new o-ring is because there was one on it when I tore it apart. We bought the zd 323 mower new, so I am almost positive it had not been tore down before we bought it. The gasket I got is exactly like the one I took off.

I did have the head leak tested, and it checked out good.

I also ordered and installed new head bolts when I rebuilt it but sounds like I didn't need them. I guess I have a good used set if anyone needs them.

I have a new gasket and will be installing that soon without o-ring. The gasket does not have a cut out for the o-ring, and neither did old head gasket which is what is puzzling to me since there was a blue o-ring there upon tear down.

Thanks again for all the valuable info. I will let you know results when I get it finished. Its about time to start using it around here.