JD LX279 blowing a lot of smoke on start up

Smokeeater

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If you don’t find water in the fuel, you may have a head gasket that is leaking. You may not notice coolant being burned off while running, but it will enter the combustion chamber after shut down and burns off at startup. You’ll need to do a leak down test to verify the problem.ing over??
Rivets, I think you may be right..I let it sit and thought I noticed the coolant level in overflow had dropped...So I marked it to see what happens after I start it again and then let it sit
I also am thinking if there was coolant in there, couldn't I remove spark plugs to see if coolant comes out on crank
 

Smokeeater

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Like rivets said. You need to do a leak down test. When you pressurize the cylinder you remove the coolant pressure cap and check for bubbles. If leakdown test shows high loss probably has a blow head gasket.
Now I wish I bought a leak down tester
 

bertsmobile1

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Rivets, I think you may be right..I let it sit and thought I noticed the coolant level in overflow had dropped...So I marked it to see what happens after I start it again and then let it sit
I also am thinking if there was coolant in there, couldn't I remove spark plugs to see if coolant comes out on crank
YEs but it might be very hard to see.
White smoke is actually steam, well to be precise it is dry super steam.
To get an ida about volume increase, a milk carton ( about a US quart ) of water makes a 8 lane 50 yard olympic swimming pool of dry super seam by volume at atmospheric pressure.
So a 5 gallon drum of white smoke will be caused by a few drops of water.
However what does work is to pull the kill wire off & crank the cold engine for 20 seconds then pull the plugs
Usually you will see little drops of water in the plug.
If you have a bore-o-scope, whan you look down the bore you will see a bit of a water line down the side where the ring gap was but you have to know what you are looking for .
 
D

Deleted member 97405

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If you don't have a coolant leak, then all is well as long as the smoke clears up. Kawasaki V-Twins are known for allowing oil to pool up behind the lower cylinder. The longer they sit, depending on the angle the machine is parked, the more oil pools in the lower cylinder. On startup, the engine will blow the oil out the muffler. If you verified you do not have a coolant leak, then you're fine. I had a few air-cooled versions of your engine that the factory had the lower piston installed upside down and was allowing an excessive amount of oil to pool up behind the piston.
 

davelakeside1

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You can also try running the tractor with the radiator cap just a 1/4 turn loose so that pressure does not build up. Run it for a short while to warm it all up making sure it doesn't overheat. Shut it down and let it cool overnight. Start it up next AM or so, and see it the problem go away.
If it does, then it's a leak somewhere in the engine read head gasket most likely. Reason is with the cap on, the water pressure in the cooling system overcomes the cylinder compression pressure and allows coolant to enter the cylinder. When it starts up it blows out the water, white smoke, for a few seconds. You may also see a few bubbles in the radiator with the cap off, sometimes hard to see, and sometimes very obvious, That's why the cap off procedure works pretty well sa there is nothing forcing the coolant in. The coolant coming in might only be 1/4 teaspoon full so checking water level is a slow procedure. Outside engine cooling leaks are usually very obvious as there is a puddle somewhere, even if you have to put a piece of cardboard down to find it, and be careful water runs along anything in the way during the drip
and ends up on the cardboard a foot away!
 
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