Diesel engine help advice needed

[nhironworks]

I just bought a Kubota L3600. Has a 4 cyl. diesel engine. about 1100 hours. I bought it knowing it had issues, smokes, ALOT. I have had lots of diesels, this one SMOKES. Prior owner "said" it ran fine and did not smoke like it does now prior to it being stored for about 3 years. The blow by out the vent tube is more of a vapor with oil. If it sits a few minutes it will leave a back spot on the ground about 8" in diameter from the vapor/oil blowing down so much, even at idle. Exhaust smoke is fairly blue. Vapor smoke is sort of clear with lots of black carbon looking oil in it. Runs great. lots of power. Starts easily cold or hot. Just smokes. I know it is most likely rings or valve guides, but wondering if there are any other possibilities. Thanks for the help! Eric

 

[mobilus]

Did you check the air intake system for blockage?

 

[Phillip w]

My guess is they if was sitting for 3 years, the rings are the problem. I may have scared the cylinder wall. I had an engine one time that say about three years and was stuck. I pulled the plug and shot penetrating oil in each hole. I got it freed up and it had problems with smoking and using oil. Blue colored smoke tends to indicate that you have oil getting by the rings.

 

[Egon]

Valve seals???

 

[Jerry/MT]

I just bought a Kubota L3600. Has a 4 cyl. diesel engine. about 1100 hours. I bought it knowing it had issues, smokes, ALOT. I have had lots of diesels, this one SMOKES. Prior owner "said" it ran fine and did not smoke like it does now prior to it being stored for about 3 years. The blow by out the vent tube is more of a vapor with oil. If it sits a few minutes it will leave a back spot on the ground about 8" in diameter from the vapor/oil blowing down so much, even at idle. Exhaust smoke is fairly blue. Vapor smoke is sort of clear with lots of black carbon looking oil in it. Runs great. lots of power. Starts easily cold or hot. Just smokes. I know it is most likely rings or valve guides, but wondering if there are any other possibilities. Thanks for the help! Eric

I think your compression rings as well as the oil control rings are stuck especially because of the blow by you are describing. Diesels run with an "open manifold". There is no way to throttle the air like in an SI engine. A clogged air filter can cause some manifold vacuum but that won't cause the problems you are seeing.

You can try putting a few ounces of ATF or marvel Mystery Oil, or even engine oil in each cylinder and let it sit for a few days. Add some more, and after a week try to start it and see if that helps.

 

[sd455dan]

I just bought a Kubota L3600. Has a 4 cyl. diesel engine. about 1100 hours. I bought it knowing it had issues, smokes, ALOT. I have had lots of diesels, this one SMOKES. Prior owner "said" it ran fine and did not smoke like it does now prior to it being stored for about 3 years. The blow by out the vent tube is more of a vapor with oil. If it sits a few minutes it will leave a back spot on the ground about 8" in diameter from the vapor/oil blowing down so much, even at idle. Exhaust smoke is fairly blue. Vapor smoke is sort of clear with lots of black carbon looking oil in it. Runs great. lots of power. Starts easily cold or hot. Just smokes. I know it is most likely rings or valve guides, but wondering if there are any other possibilities. Thanks for the help! Eric

As a Test
i would pull the exhaust manifold (assuming not turboed) and fire it up... If it is just 1 cylinder with a problem you will know which 1 to concentrate on re working. If all 4 smoke out each port equally then may need a set of rings and / or head rework, might want to verify injection pump timing to
Does the tractor have a miss at idle? I know you said it starts great with lots of power.

 

[laurencen]

had a similar issue on a Bobcat 843, turned out the rings were stuck solid in the grooves of the piston

 

[nhironworks]

I removed the air cleaner, it was about the worst I have seen. Seems to be open. I am going to try putting some penetrating oil of sorts in the cylinders and let it sit a bit. Thanks!

Did you check the air intake system for blockage?

 

[nhironworks]

The oil is very thick, "sludgy". I am changing it today and will let it run a while. Going to try letting some mystery oil sit in the cylinders a week or so and see what happens. Thanks fr the help.

 

[ericm979]

Excess air and fumes coming out of the crank breather is a sign of too much blowby past the rings. Hopefully clean oil and filters and soaking the rings will help unstick the rings.