BX Series D722 Engine Cylinder Head O-ring?

[mak1976]

Did a search and didnt really see anything specific to help me.

Background - I have a 2006 BX1850 that has been overheating/puking coolant etc...Did the usual troubleshooting and ran a coolant test that indicated combustion gases we present in engine coolant. That made me think cylinder head gasket.

So that leads me to my question, my kubota WSM states there is an O-ring that goes around the alignment pin along with the cylinder head gasket, but I did not see one when I removed it but I guess it could have rolled away somewhere when I lift the top off but I was being careful.

See my pic from WSM with arrows pointing to the O-ring.



Now my issue is I also have the parts manual that doesn't seem to show any O-ring for me to order...Even called a big Kubota Parts dealer and they could not answer so hoping someone here might have some ideas.

Here is the parts manual pic as well...



Anyone know what the O-ring part number is?

Thanks

-Andy

 

[DeepandDirty]

You can try asking here GENUINE KUBOTA ENGINE HEAD GASKE O RING PART # 15221-337 | eBay

 

[Peter 315]

Maybe it comes with the new head gasket....:confused3:

 

[mak1976]

I have the new gasket package, no o-ring, but I think DeepandDirty might be right. I will research that part number.

 

[mak1976]

Update, I ordered the part DeepandDirty suggested after some educated assuming. I have a feeling my BX1850 work shop manual is more accurate that the bx1850 parts diagram I have.

I'm thinking the document writers from Kubota simply missed that part number from my BX1850 parts manual. When I compare the parts manual from the BX1830 (same engine as mine just one year older), there is exactly 1 part difference and that is this mysterious pipe pin O-ring.

I'm wondering now if my tractor never had one in it since I never saw when I pulled it apart. I guess the old o-ring could have also completely disintegrated perhaps? Not sure I bought it used and abused so not sure what life it had before me.

 

[mak1976]

O.k. latest has me second guessing myself. The WSM for the BX1860 specifically states NOT to use the o-ring now.



So here are the facts...

BX1830 (D722 motor) - WSM says use o-ring and parts manual has it listed. Latest supported cylinder head gasket is part# 16871-03313
BX1850 (D722 motor) - WSM says use o-ring but parts manual does not have it listed. Latest supported cylinder head gasket is part# 1J092-03310 whiched replaced 16871-03313
BX1860 (D722 motor) - WSM for the BX1860 specifically states not to use the o-ring now and parts manual does NOT have it listed. Parts look same as my 1850. Latest supported cylinder head gasket is part# 1J092-03310

I'm thinking some small revision was made by the engineers of the d722 in between the years. Notice the difference in the latest supported cyclinder head gasket for each machine. I'm thinking my bx1850 was caught in between having to use the o-ring and not having to use it based on the head gasket type. I can say the old gasket I pulled out of my bx1850 looks slightly different than the new replacement Kuboa says I should use.


So my question is o-ring or no o-ring....Might flip a coin tonight...Leaning towards no o-ring though...

Any thoughts?

 

[DeepandDirty]

Is there an indent in the mating part for the O-ring to sit into?

 

[mak1976]

Is there an indent in the mating part for the O-ring to sit into?

You had to ask, yes there is a slight indent around the "pipe pin" maybe fingernail thickness if that.

Here is a pic of the ident around the pipe pin where the o-ring "might" go, it's the dark area around pin...see red arrow....



Here is pic of the o-ring part I ordered.



I just noticed this o-ring part has a serial number "break" which usually means there is a replacement part, but there is no new serial number replacement. So now I'm getting more confident they just stopped using this part when they brought out the latest head gasket for my tractor...The o-ring looks much larger and maybe overkill for this small indent IMHO but might wait until I get the o-ring and see if it looks like it will work better when its on the pin?


Thanks for any ideas, experiences or encouragement... ;-)

 

[dpri8977]

Did a search and didnt really see anything specific to help me.

Background - I have a 2006 BX1850 that has been overheating/puking coolant etc...Did the usual troubleshooting and ran a coolant test that indicated combustion gases we present in engine coolant. That made me think cylinder head gasket.

So that leads me to my question, my kubota WSM states there is an O-ring that goes around the alignment pin along with the cylinder head gasket, but I did not see one when I removed it but I guess it could have rolled away somewhere when I lift the top off but I was being careful.

See my pic from WSM with arrows pointing to the O-ring.

View attachment 676705

Now my issue is I also have the parts manual that doesn't seem to show any O-ring for me to order...Even called a big Kubota Parts dealer and they could not answer so hoping someone here might have some ideas.

Here is the parts manual pic as well...

View attachment 676706

Anyone know what the O-ring part number is?

Thanks

-Andy

You had to ask, yes there is a slight indent around the "pipe pin" maybe fingernail thickness if that.

Here is a pic of the ident around the pipe pin where the o-ring "might" go, it's the dark area around pin...see red arrow....

View attachment 676890

Here is pic of the o-ring part I ordered.

View attachment 676891

I just noticed this o-ring part has a serial number "break" which usually means there is a replacement part, but there is no new serial number replacement. So now I'm getting more confident they just stopped using this part when they brought out the latest head gasket for my tractor...The o-ring looks much larger and maybe overkill for this small indent IMHO but might wait until I get the o-ring and see if it looks like it will work better when its on the pin?


Thanks for any ideas, experiences or encouragement... ;-)

Hello, here is a picture of the part number and the o ring. It is not necessary! I just built this kubota d722 turbo engine and didn't even use one. Flip the head over and the hole is bigger than the o ring and truthfully wouldn't even do anything. Hope this helps, God bless everyone!