# 2203M Missing/Smoking bad on Cold Start.... WHY ?



## labrat0116 (Dec 21, 2021)

On cold start, the engine fires right up but has a bad misfire and blows blue smoke like a freight train.

After 3-4 minutes, the engine stops misfiring and the smoking goes away and runs great.

Bad/Sticky fuel injector or bad valve seal/guide in one cylinder ?

How to determine the difference ??


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## unsquidly (Jul 13, 2021)

Blue smoke is oil smoke......I would say that it is not an injector based on the color of the smoke. Sounds to me like you have oil setting on the top of the head and seeping down into a cylinder once you shut the tractor off...Not sure about the Kubota diesels but I have had this in diesel and gas truck engines before and sometime it was as simple as pulling the valve covers and cleaning out the oil return channels. Other times it was a valve or a valve seat or an injector cup.

I am going to let someone smarter then me on Kubota diesel engines chime in here now.....LOL

One other thing to check is to make sure that you don't have diesel fuel in your engine oil.....

It could also be a glow plug.....I have seen diesels blow blue smoke with a bad glow plug until they get warmed up.....


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## LouNY (Dec 15, 2016)

Check your glow plugs likely one bad one, takes time for that cylinder to warm up and run with the others.


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## labrat0116 (Dec 21, 2021)

Glow plug.... yes. Good place to start.


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## unsquidly (Jul 13, 2021)

Before you do that, check your oil and make sure that you don't have any diesel fuel in the oil......If you do, It is not glow plugs.....


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## thepumpguysc (Jan 25, 2015)

Pull dip stick..1st.
Next, start the engine like u normally would.. get it smoking..
Now, loosen the injector line AT THE INJECTOR & watch the smoke..
If it clears up, THATS the problem cyl..
IF NOT, retighten the line and move to the next one.. until u narrow it down to a cyl..


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