D722 please help I am an idiot

Joemoy29

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Oct 1, 2016
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Freehold nj
I have a bobcat mt50 has a kubota d722 non turbo. I have owned the machine for a couple years and it is a beast. The gauge panel is rough and there is a idiot light for fluid. I had a bad hydro leak on a drive seal. Finally get the parts (bobcat sucks and sent me only half the parts first time). Get the seal fixed put some hydro fluid in it.

Start the machine and no leak. Yah I am awesome....the idiot light is still on so I put some more hydro fluid and then it starts overflowing resivour?????? Guess what there is two idiot lights this on is for oil. Before I realized this it started tapping a little and shut it right off.

Check the dip stick no oil. Yeah I am an idiot. I run out and grab some oil and fill it up and fire it up runs fine but blows white smoke out of exhaust. And leaking oil bad from filter area. I go to change the filter and it is on by two threads. Pull it off put new on. Fresh oil and still smokes white getting worse with higher rpms.

Dealership tells me head gasket so I order and switch. (Cylinders look fine no scoring) Fresh oil again and I fires right up, makes power but same issue with white smoke.

I am at a loss any help or suggestions are greatly appreciated.
 

Tooljunkie

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D722 usually blows coolant when head gasket fails.
White smoke even at operating temperature?
Check air filter,and replace fuel filters while you are there.
 

North Idaho Wolfman

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I'll bet it's actually blue smoke (oil) and it because it fried the rings when it ran dry.
Or it's flooding a cylinder from either a bad injector or low compression.
Do a compression test on it. ;)
 

Joemoy29

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Freehold nj
Thanks for the reply. It's making normal power so that's why I didn't think low compression. This is a dumb question but I am not a diesel guy. But how do I do a compression check if there are no plugs?
 

Wild and Free

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There are plugs.............glow plugs that is lol. You can do a compression test through those ports.
 

torch

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You will need a diesel compression tester kit with the appropriate size glow plug adapters and appropriate range pressure gauge.
 

Delmar

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Sep 24, 2015
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I recently went needed to test compression on a D722 engine also. I found that the properly sized glow plug adapter had a quick connect end that is smaller than a normal air quick coupler. I searched everywhere and it seems that it might be a proprietary fitting that only fits the Kubota compression gauge. None of the compression tester kits I checked had an adapter that would work. Frustrating!

I found, however, that paint ball guns use the same connecter. Ordered one of these and it worked great! https://www.amazon.com/gp/product/B0094TZVKC/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

Good luck.
 

coachgeo

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My Harbor Freight Diesel Compression tester had a Kubota fitting.
 

Delmar

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I think the D722 requires a smaller fitting than the one in HF kits. True, at least, for the kits in stock in my area. The D722 requires an 8mm - 1.0 fitting for the glow plug hole. Here's a link to the one I bought:
https://www.toolsource.com/engine-s...sion-test-adapter-8mm-100-kubota-p-97782.html

You'll notice the "quick connect" end. I didn't even think about it being a different size until I tried to attach to my gauge. I didn't even know there was a smaller quick connect fitting! However, the paint ball adapter worked fine.

I also tried to find a fitting in several kits for the injector port to no avail.
 

EzDuzIt

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I recently went needed to test compression on a D722 engine also. I found that the properly sized glow plug adapter had a quick connect end that is smaller than a normal air quick coupler. I searched everywhere and it seems that it might be a proprietary fitting that only fits the Kubota compression gauge. None of the compression tester kits I checked had an adapter that would work. Frustrating!

I found, however, that paint ball guns use the same connecter. Ordered one of these and it worked great! https://www.amazon.com/gp/product/B0094TZVKC/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

Good luck.
Holy cow! I know this post is over 2 years old but Delmar just saved me a butt load of frustration.

I too just purchased a Harbor freight for my D902 engine (same super mini series engine as the 722) and found that the couplers that came with it would not fit my M8x1 heat plugs. I also found the same link for the same M8-1 fitting which I am about to purchase.

Never in a million years would I have figured out the paint ball gun connector! Come on guys. This type of detail is in need of a sticky! Had I not accidentally stumbled across this thread, I would have run through all sorts of additional pain. Is there any moderators that collects this and post stickys for the different generation kubota's?

Anyways, big props to Delmar for the huge hint! I owe you a beer!
 
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coachgeo

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...This type of detail is in need of a sticky! .... Is there any moderators that collects this and post stickys ...!
Yes there is. Check the Ultimate sticky at the top of each forum. It is a menu to great threads on specific topics.. just like this one.
 

GeoHorn

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That paint ball adapter apparently uses common 1/8" NPT threads...and that is so common that it is laughable. Why wouldn't you simply use a common hardware store version of the adapter?
 

North Idaho Wolfman

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That paint ball adapter apparently uses common 1/8" NPT threads...and that is so common that it is laughable. Why wouldn't you simply use a common hardware store version of the adapter?
I don't think your understanding...The glow plug adapter is a special adapter that is 8MM on the glow plug side but a quick connector on the other, a 1/8" NPT thread would not help him in the least. ;)

EDIT: I get the confusion as there are 2 links posted, the second link is just a coupling, not what he needs, this is what he needs, first link:
https://www.toolsource.com/engine-s...sion-test-adapter-8mm-100-kubota-p-97782.html

 

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John1953

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I don't think your understanding...The glow plug adapter is a special adapter that is 8MM on the glow plug side but a quick connector on the other, a 1/8" NPT thread would not help him in the least. ;)

EDIT: I get the confusion as there are 2 links posted, the second link is just a coupling, not what he needs, this is what he needs, first link:
https://www.toolsource.com/engine-s...sion-test-adapter-8mm-100-kubota-p-97782.html

I ordered this item and tried to use it on my B7500 engine (D1005) ...the threads were not a perfect match and I did not want to screw up the threads on my tractor... ordered another one but it was shallow against the head....I could not get the gauge hose to properly fit to get a good read....any one else know a better adaptor?