Kubota L3400 Blue Smoke

[Robert walker]

I have a 2004 Kubota L3400DT that started smoking when I start it and when I accelerate. If I push the throttle it will puff out blue smoke, I know it’s burning oil, I can smell it. i bought this tractor new, it has about 900 hours. Have always changed the oil at 200 hours. Could I have valve stem seals leaking or do y’all think I need to put new rings in it? Another issue that started not too long ago is that it will start right up cold, big puff of blue smoke, but once it warms up if I turn it off it’s hard to get it to turn over and fire back up. I know it’s a lot but I have to tear it down and get it fixed.

 

[dodge man]

I’m not a lot of help but I’d figure out what’s wrong before tearing it down, it might be something minor. Do these have a PCV valve on them? I’d start there and check that. 900 hours is nothing on a diesel engine unless it was overheated or neglected.

 

[Tomtint]

Start with the easy stuff...Like checking the air filter.

 

[Thomas]

Are you using fresh diesel?
What RPM's do you run?

 

[Jerry/MT]

I have a 2004 Kubota L3400DT that started smoking when I start it and when I accelerate. If I push the throttle it will puff out blue smoke, I know it’s burning oil, I can smell it. i bought this tractor new, it has about 900 hours. Have always changed the oil at 200 hours. Could I have valve stem seals leaking or do y’all think I need to put new rings in it? Another issue that started not too long ago is that it will start right up cold, big puff of blue smoke, but once it warms up if I turn it off it’s hard to get it to turn over and fire back up. I know it’s a lot but I have to tear it down and get it fixed.

How hard do you work it? Your oil control rings might be loaded up with carbon from not getting the engine up to temperature long enough. Are you using a Diesel rated lube oil in the engine?

At 900 hrs, I doubt it's a compression problem but since it's 19 years old and only has 900 hours on it, me thinks it hasn't been worked hard. Before you start tearing it a part, work the snot out of it for about 10-20 hours and see if you get some improvement.
As far as hard starting when hot, make sure that the battery and the chasis ground connection terminals are "bright and tight". How old is your battery? Have it tested.

 

[Robert walker]

How hard do you work it? Your oil control rings might be loaded up with carbon from not getting the engine up to temperature long enough. Are you using a Diesel rated lube oil in the engine?

At 900 hrs, I doubt it's a compression problem but since it's 19 years old and only has 900 hours on it, me thinks it hasn't been worked hard. Before you start tearing it a part, work the snot out of it for about 10-20 hours and see if you get some improvement.
As far as hard starting when hot, make sure that the battery and the chasis ground connection terminals are "bright and tight". How old is your battery? Have it tested.

I mow pastures with it in the fall, gonna start early this year probably. I don’t go fast but I pull a 6’ mower with it. i have a couple spots that I’m going to mow in 3 weeks, I sprayed them today, trying to kill cockaburs. While I have abused it, I do feel like I have worked it hard since I bought it. I will give it a try. I do plan on changing all fluids before I start mowing.
Seems like the battery isn’t but 3 years old but I have a new one I bought for something else and ended up not using it. I’m gonna charge it, and swap it out to see if that will take care of that problem. Thanks

 

[Jerry/MT]

I mow pastures with it in the fall, gonna start early this year probably. I don’t go fast but I pull a 6’ mower with it. i have a couple spots that I’m going to mow in 3 weeks, I sprayed them today, trying to kill cockaburs. While I have abused it, I do feel like I have worked it hard since I bought it. I will give it a try. I do plan on changing all fluids before I start mowing.
Seems like the battery isn’t but 3 years old but I have a new one I bought for something else and ended up not using it. I’m gonna charge it, and swap it out to see if that will take care of that problem. Thanks

How tall is the grass and how long of time are you operating the tractor when you mow? Does your coolant temperature indication move up a bit when you are mowing due to increased load? ( not because the radiator is clogged with chaff).

 

[Robert walker]

How tall is the grass and how long of time are you operating the tractor when you mow? Does your coolant temperature indication move up a bit when you are mowing due to increased load? ( not because the radiator is clogged with chaff).

Yes, it will go up some. Right not it’s mostly weeds and about 2’

 

[Robert walker]

Start with the easy stuff...Like checking the air filter.

I replaced the air filter and that helped a lot. It had about 200 hours on It give or take 50. i Took the negative battery cable off and cleaned both ends, went to start it and it went to turn over and quit. I think the hard starting part of my original post may have made the starter relay eat the dirt. Gonna trouble shoot it this morning. It’s been too hot in east Texas to do much during the day.

 

[workinonit]

Personally I don't think running a bush hog is going to load it to the point that Jerry is referring to. I can pull a 21 foot finish mower and don't see much increase in load at all. probably 10%. Once you spin up a bush hog it doesn't require much to turn it unless you get it in some really thick stuff.