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Cub Cadet riding lawn mower is 2-3 years old. It has white billowing smoke when the blade drops down to cut. What things should I be checking. Is this something I can fix at home perhaps? the small engine shop says they are behind 2-3 weeks.

Where is the smoke coming from? Is it coming out the exhaust or from the the mower deck? If it is coming from the exhaust you may have put too much oil in the crankcase. If it is from the deck it must be the belts. Something is not turning or the belts are not on correctly. I know this isn't much help but more information is needed for this one.

2008-04-28 15:36:36 by smpmsu1980

I show how to replace the bearings in the LT1045 and how to put on the new gator mulching blades. Hope this helps some people out there.

My Cub Cadet lawn mower during the last couple mowings has let out a huge white cloud of white smoke through the exhaust and the engine misses for about 10 seconds and then it's fine again. It only seems to happen when I'm on an incline. The mower is only 2 years old and I'm afraid the engine is going to blow. I had changed the oil this spring, sharpened the blades, and lubed everything. WHAT'S GOING ON??? It has a Briggs engine and still has full power. All I can think of is that the oil rings on the piston are failing, but I'm no expert. I am mechanically enclined, but don't know where to start. HELP!

The Incline is the "clue".
But not necessarily anything about the rings.

If the rings were bad it would smoke all the time.

The crankcase vent system on those type engines is
deliberately very primitive for certain reasons.

It's about a 3/8" or 1/2 " hole drilled from the Valve Spring Chamber into the crankcase.

That Chamber has a hose connected from it to the carburettor.
Purpose is to inhale and burn the crankcase oil vapours.

If you turn the engine on it's side,,,the oil will literally flow out of that hole,,fill the chamber,,and pour out of the vent tube.

You can actually Drain the engine oil thru the Carb on a Briggs if you position the engine in a certain way.

As fine & capable a machine as a Cub Cadet is,,,
I Doubt you were moving an incline steep enough to have the engine Upside Down or literally on it's side...LOL:)

Nevertheless,,,in Certain DIRECTIONS the Engine does NOT have to be very Much off of a Horizontal plane to Throw a BUNCH of oil towards the Vent Hole.
It overwhelms the Drain Back capacity,,,,and the excess oil gets sucked into Engine thru the Carb.

Which makes a BUNCH of smoke,,,and runs VERY bad.
That's If it doesnt kill the spark plug outright,,from Oil Fouling.

The Actual AMOUNT of oil is usually VERY small.
Even a few drops,,, makes a BUNCH of smoke,,
1/4 teaspoon would smoke for MANY,Many minutes.

What you can do to Minimize the Occurence,,is simply to mow that Incline in Opposite Direction.
No kiddin'.

Reason why that works is this,,, There is a BAFFLE inside the crankcase to prevent the oil which is being slung around from being thrown Directly towards the Vent Hole.

When machine is on Level Surface...
The Baffle's Opening is HIGH in the engine,,,well above Oil Level.
And it is OFFSET towards the Output Shaft side.
Any Oil which gets past the Baffle,,,simply drains back into Engine.

Here's a Picture>>>>
http://www.mdcmotorsports.com/Mvc-013s.j pg

Notice the Semi-Circular cavity towards the Left/Upper corner of the Inside of the cranckcase.

That is the "Baffle",,,
"nothing but fumes and windage/crankcase pressure" is supposed to be in that area.

Notice 2 things,,,the inner edge does NOT come out to the gasket surface.
That creates the GAP thru which the engine BREATHES when the Cover is in-place on the assembled engine.,,,
and it drains back any accumulated oil.
2nd,,notice the Hole up in the top of the cavity,,a light spot in the shadow.

Heres a REAR View ,,different Block,,but "same type setup"
http://www.peaknet.net/~tompav/pics/DSC0 3586.jpg

The Shiny Rectangular Cavity is where Valves/Springs are.
You can see the "Rounded Hump" directly below the cavity.

The Vent hole connects those 2 cavities.

The External,Rectangular cavity gets a COVER over it
with a One-Way Check Valve Fitting for the Vent Hose which goes to Carb/AirFilter.
The "PCV" valve,,such that it is.

Going back to the pic of the Inside of the crankcase.....
And the Semi-Circle Vent Cavity.

OK,,That's a Horizontal Shaft Engine....as used on Most Edgers,,,MiniBikes etc.
Spark plug straight up in the air.

You can see how Gravity would Drain any oil from the the Vent Cavity.
Imagine laying that engine down as it's setting in that box,,,on a Table Top.
Which is on it's SIDE,,,Versus standing straight up as it normally would be in actual operation,

If you put oil in that Vent Cavity,,in that exagerated position,,,
Would Gravity Drain it??
Noooo,,,in THAT "laying on it's Side" position,,,,,
The Gravity-Drained Cavity becomes nothing more than a CUP which Holds Oil.

So while that is Filled with Oil,,,Recall the VENT HOLE supposed to be at TOP of the cavity.
Then it would be Then be oriented in " LOWER SIDE",,,below the level of the accumulated oil.

Like a Teapot with a spout,,,lay it on its side and the stuff runs out the spout,,,right?

A Briggs' "spout" goes directly to Intake Tract.
Any excess oil in Breather system gets sucked into engine.

All that is Grossly Exagerated to illustrate what's happening when operating the engine on an incline.

It does NOT actually FILL with oil.

But rather than Draining Totally and Staying EMPTY,,
When Engine tilts in that One Direction SOME OIL DOES Puddle & accumulate in there.

All while the Engine is Pumping a LOT of Air Volume thru that Vent Hole each time Piston Goes Down and compresses the air in the crankcase.

AND while the Rectangle Breather Cavity is under VACUM from Intake System/Carb's airflow.

A Short Time on an Incline doesnt raise level of oil caught in the breather system to any significant degree.

It usually only gets a Misty Splash of oil.

But at some point on Incline,,,and after some length of time...
Enough oil DOES get captured in the area where it's NOT supposed to.
And it DOES get Pumped from one end while being Vaccumed from the Other.

So,,,the engine smokes like hell is b-b-q'n.

The condition also explains why it "Comes and Goes".

Also explains why I wasn't just being a wise-guy by saying,,"Mow in Opposite Direction.

In One Direction,,,You're effectively holding the "cup" Upright allowing it to accumulate oil.
In the OPPOSITE direction,,it's literally Bottoms Up.
..........................................................
OK,,,on a VERTICAL SHAFT engine,,,the Baffle/Breather Layout is Different.

The Inlet is well above Oil Level,as always.
But again,,,,
Tilt engine in One Direction and the Oil Level moves AWAY from Breather Opening--- so,No Probs sucking Oil.

But when tilted in Opposite Direction,,,,
Oil Level RISES towards the Breather system.

As the Engine's windage and it's oil-slinging begin to blow oil Across the HIGHER LEVEL/Narrower Distance to the Breather,,,
and while Carb Intake Vaccum is Sucking on it from the downstream end of the Breather Tract..
Some Oil WILL get aspirated into Engine.
.....................................................................................................
I seriously doubt it's a problem with the rings.

It probably just slung an accumulation of oil into the breather system and flooded the Baffle Cavity.

Often you can see the excess oil on the Inside side of the Air Filter.
You may want to check that Air Filter is not oil saturated,,,especially if it's newer type Pleated Paper Filter

.............................................
If you are concerned about engine life,,,
try 30 weight Valvoline VRI Racing Oil,,
or 40 if you live in 100*+ Summer climate.
Yes it's Detergent Oil which is NOT recommended in Splash Lubed motors.

The Reason NON-detergent is specified is due to Foaming.
Valvoline VRI is more than sufficiently NON-Foaming

Get some PTFE/Teflon based oil additive (Slick-50 type snake oil).
WalMart usually has cheaper ,comparable products.

Shake it Thoroughly>
Pour it in a 2 Liter Soda Bottle so you can "watch it">
Let it sit several days till it settles.
Sounds goofy,,,but vibration will help precipitate the desirables---carry the bottle around in your car secured so it cant fall over and "re-mix",,,
or even on the Cub next time you mow.

You want it Shaken,,,Not Stirred.

Anyhow,,,once it separates well,,
You'll see a Clear ,Thin Upper layer,,,and a milky,thick-ish looking sludge on the bottom.

Pour off the upper part.
You wont have Much left to keep & use,,,
Maybe 1/4 of the original quart???MAYBE.

Pour all of the teflon "sludge" into the Cub's motor at next oil change.
Then top up with Good Motor Oil.

Or Not,,
,just a suggestion on the oil/additive.


In any case,,,if you had Ring Probs of any sort,,the symptoms would be Consistant and manifest themselves ANY time the engine was running.

I beleive you are most probably just experiencing a quirk of how those engines are built & react in certains conditions.

Good Luck with it

2007-05-08 16:42:34 by Crox Trader

international cub cadet 104 ,Kolher,10 horse motor ,model#K241A, ser#E0072693, spec#46407D . need front clutch pully off motor to run blades

I would think that any small engine repair shop could get you the parts you need.

2007-07-04 08:39:05 by connerelva