B7300, D722 Cylinder Head Plug

[Keystone B7300]

Hey everyone,
So i'm in process of replacing the head on my B7300 (D722 engine). the old head cracked in the rear (towards driver) behind a set screw/plug. I was looking at welding it, but decided to just replace the head.

I looked at my local ACE for a replacement plug and couldn't find a match. the plug is 15841-96020. Its #90 on the attached diagram (also included what it looks like). I can't use the old one, had to remove it with an easy out.

Does anyone know the thread pitch & size of that bolt? or a common alternate? I can't find anything on this screw/bolt anywhere. I know its sounds simple, I had 2 guys try to help me at ACE and couldn't find it.

Also, the tractor seems to have potentially over heated (it actually cracked when i throttled down and turned off the machine). Is it common to replace the waterpump? Wanting to do a full service while I have it broken down.

Finally, I seem to have accidentally unscrewed the top half from the bottom half of an injector (if that makes sense). Can I just torque the injector back together? Couldn't find anything on that either.

 

[Keystone B7300]

Also, Thanks for the help!

 

[Tire Biter]

Probably gonna have to get one at the dealer. Or:
https://parts.mbtractor.com/item/15841-96020/

 

[jack1091]

Hey everyone,
So i'm in process of replacing the head on my B7300 (D722 engine). the old head cracked in the rear (towards driver) behind a set screw/plug. I was looking at welding it, but decided to just replace the head.

I looked at my local ACE for a replacement plug and couldn't find a match. the plug is 15841-96020. Its #90 on the attached diagram (also included what it looks like). I can't use the old one, had to remove it with an easy out.

Does anyone know the thread pitch & size of that bolt? or a common alternate? I can't find anything on this screw/bolt anywhere. I know its sounds simple, I had 2 guys try to help me at ACE and couldn't find it.

Also, the tractor seems to have potentially over heated (it actually cracked when i throttled down and turned off the machine). Is it common to replace the waterpump? Wanting to do a full service while I have it broken down.

Finally, I seem to have accidentally unscrewed the top half from the bottom half of an injector (if that makes sense). Can I just torque the injector back together? Couldn't find anything on that either.

Did you ever find out what size that plug was I'm curious as well thank you

 

[Russell King]

Did you ever find out what size that plug was I'm curious as well thank you

That person hasn’t been back to the forum since late 2020 so I doubt they will be giving you any answers!

I would guess that it is a BSPT plug and you could try to see if there is an adapter that fits it from a engine temperature sensor adapter kit for Japanese cars. Those are available at auto parts stores and are used to adjust the engine port to the temperature sensor thread.

Messicks has one PLUG in stock so your local dealer or Messicks should be able to get you the plug if that is what you really want. See this link for some rough measurements of the plug.

Kubota #15841-96020 PLUG***

PLUG***

www.messicks.com

Here is some information on that thread type. I would GUESS 1/8 size and tapered.

British Standard Pipe - Wikipedia

en.wikipedia.org

 

[jack1091]

That person hasn’t been back to the forum since late 2020 so I doubt they will be giving you any answers!

I would guess that it is a BSPT plug and you could try to see if there is an adapter that fits it from a engine temperature sensor adapter kit for Japanese cars. Those are available at auto parts stores and are used to adjust the engine port to the temperature sensor thread.

Messicks has one PLUG in stock so your local dealer or Messicks should be able to get you the plug if that is what you really want. See this link for some rough measurements of the plug.

Kubota #15841-96020 PLUG***

PLUG***

www.messicks.com

Here is some information on that thread type. I would GUESS 1/8 size and tapered.

British Standard Pipe - Wikipedia

en.wikipedia.org

Okay thank you I'm hoping it's a 1/8 thread size because that stuck size of the threads of the water temperature sensor that I ordered thank you for replying back

 

[Russell King]

Okay thank you I'm hoping it's a 1/8 thread size because that stuck size of the threads of the water temperature sensor that I ordered thank you for replying back

Please note that the American pipe thread is different than the British pipe thread. They can probably be put together but they won’t seal the pressure in the water jacket. You will need an adapter like this if the sensor is NPT thread.

https://www.autometer.com/1-8-npt-to-1-8-bspt-pressure.html

If you mean that you found a sensor with 1/8 BSPT then you are hopefully good without the adapter.

 

[jack1091]

Please note that the American pipe thread is different than the British pipe thread. They can probably be put together but they won’t seal the pressure in the water jacket. You will need an adapter like this if the sensor is NPT thread.

https://www.autometer.com/1-8-npt-to-1-8-bspt-pressure.html

If you mean that you found a sensor with 1/8 BSPT then you are hopefully good without the adapter.

It's a Kubota sensor I'll double check that information though thank you I had no idea again thanks a lot for your help