L225 Blows blue smoke ONLY when under heavy load

[jason.lucia]

Okay, just bought a L225. Starts great, runs great. Good throttle response and plenty of power. No smoke at start-up or when revving. When engaging a 5' tiller, and making the engine WORK HARD, it blows a profuse amount of BLUE smoke. Idle it down and disengage the tiller, then rev it up again without being under load, no smoke at all. Engage the tiller, drop it into the dirt and make the engine WORK, it blows blue smoke. Suggestions?

I hear blue smoke is rings, but it ONLY blows blue smoke when under load.

 

[eserv]

A plugged crankcase vent will make them smoke blue when under load. As there any sign of vapor or oil coming from it when you are running the engine?
Ed

 

[jason.lucia]

None at all. I will try the crank case vent after I find it. Thanks. I will let everyone know.

 

[jason.lucia]

Okay, I assume that crankcase is called another name. The parts diagram does not show where it is located at? I am a bit of a rookie (a big rookie) and can do most mechanical things if my nose is pointed int he right direction. Where is that booger located at. Parts list on Messicks does not show it by that name.

 

[gktilton]

Typically you will see a tube venting from your valve cover and hanging to the base of the engine.

 

[eserv]

Not sure on the L225 but most Kubota's have a hose from the valve cover on the top of the engine that goes down alongside the engine to just below the oil pan bolts. It is simply a vent that allows engine vapors to escape. if it gets kinked or plugged some way (often here in Alberta they get frozen, we've seen a lot of them this winter frozen up!) the crankcase will pressure up pushing oil past the rings and anywhere else it can get out.

 

[daniel.ray77]

The vent tube on the L225 comes out of the valve cover and runs down alongside the left side (exhaust side) of the engine and dumps out right next to the oil pan. On my L225DT it empties in between the front propeller shaft and engine oil pan. Can't miss it. Its rubber and about 1/2 inch in diameter.

 

[meanjean]

Great advise regarding cause of blue smoke.
I will be storing that nugget of info away.

 

[jason.lucia]

Okay, the crank case vent is open and not clogged. I put my finger over it and it is breathing good.

I also removed the oil fill cap and there is no pressure blowing there. It started fine this morning, cold (20 degrees) and no blue smoke. Took her out, dropped the tilled and when bogging down, blue smoke. I'm gonna try new oil, new fuel filter and new air filter and see what that does.

 

[gktilton]

When you say "Bogging Down", are you talking like close to a stall where you are seeing a significant reduction in RPM?

 

[jason.lucia]

I apologize, I mean RPM's going slightly lower due to it being under load. It does not necessarily "bog down" it is just under load.

 

[jason.lucia]

Changes all the filters and took her out again. Ran her hard. This is what I figured out because it smoked a LOT less. After running it full bore with the tiller digging deep clay, it cleared up. Let it sit for a day, took her out the next day and viola, not more blue smoke?

I figured it was just blowing the gunk out of it since it was not used very hard from the previous owner. Fuel filter, by the way, looked like it had seaweed in it. I drained the tank completely and replaced fuel filter too when I changed oil and filters.

Thanks for the info guys. Crank case vent was not plugged though. Just needed to blow the junk out of her lungs.