Engine smokes

[Fenton]

hey! every one

can any one tell me how can check the engine here it is smokes or not.. I am waiting yours reply's.. I know Engine smoke means trouble An engine in good running condition should not produce any smoke in its exhaust. Steam is normal, and may appear to be white smoke on a cold morning. But any other type of smoke in the exhaust means something is wrong.

 

[robwkamm]

??? Start it and post a video of it for us to see. what engine?

 

[mikewint]

going to be picky here. Steam or water vapor is as invisible as oxygen. When the water rich exhaust hits the cold atmosphere water condenses into small droplets which appear white
Black smoke is caused by black particulate matter in the exhaust gasses. those black particles are soot of carbon particles. thus you have incomplete combustion i.e. too much fuel too little oxygen or you are running rich
Blue smoke indicates the presence of oil thus you are burning oil along with the gasoline. your engine cylinders/piston rings are worn. oil is being left on the cylinder walls.
that's about as far as visual detection will take you.
a gas analyzer can give you much more information: CO2, CO, Nitrogen oxides, etc.

 

[evangilder]

Are you talking about an aircraft engine, or a car engine? If aircraft, radial, flat vee, etc? What type of engine?

 

[mikewint]

evan, would it matter? if it is internal combustion we're still talking about the same mechanical components. rich mixtures are incomplete combustion which produce CO and unburned carbon, black smoke
besides seeing unburnt oil on the aircraft the burnt/partially burnt hydrocarbons should still give the exhaust a blueish cast.
I'm not an aircraft guy but I think the same principles should apply

 

[evangilder]

The kind of smoke that comes out of a radial can point to symptoms that might differ in a non-radial engine. Besides, if a car smokes, it's one thing, but when an aircraft smokes, and the hazard of complete failure makes things much more dangerous in an aircraft.

 

[mikewint]

Evan, can you be more specific about radial vs non-radial. I don't understand how the cylinder arrangement can alter the exhaust color. I can see that in some radials (like on my B-29) the rear bank runs hotter than the front bank which changes combustion conditions and in some cases (like the B-29) could lead to unseating a valve and even an engine cylinder burn through.
and a big YES on the danger element. a stalled car pulls over to the side of the road a stalled engine on a plane leads to thing falling out of the sky, not a good thing

 

[icepac]

White smoke means there is a new pope.

 

[robwkamm]

thats the best reply yet. I love it . thanks Icepac

 

[mikewint]

And he is blessing your engine, so white smoke is good

 

[Vintageaeroengines]

oil smoke is black above 1 atu of supercharger boost. Usually, oil comes from rings, valve guides and supercharger seals. Oil smoke can be white, blue or black. coolant smoke is usually white.

 

[mikewint]

Vintage, Aren't all radials air cooled? Didn't know that a supecharger could change the color. I'm guessing that the increased temp burns the oil as well?

 

[robwkamm]

got to love posts like this. original poster never chimes in after posting. whats the point.

 

[mikewint]

well if he isn't learning anything I am. Always wanted to know more about planes

 

[javlin]

well if he isn't learning anything I am. Always wanted to know more about planes

I always wanted to learn more about the pope.

 

[mikewint]

well you get to wear little red shoes and ride in the popemobile

 

[bobbysocks]

in the automotive world excessive ( billowing ) white smoke coming from the exhaust pipe is usually coolant. it should have that sweet antifreeze glycol smell with it. this comes from a blown head gasket or worse a cracked water jacket in the head or block. dark smoke from the exhaust should have that burnt carbon smell to it and usually comes from oil. a badly broken piston ring, head gasket blown around the oil return channel, or a blocked oil return holding excessive oil in the rocker covers that leak down the valve guides will do that. white oil from under the hood could be either of those or tranny and power steering fluid.

 

[vintage aero engines]

the supercharger raises the effective compression ratio of the cylinders and the oil from the induction system is fully burned like a dessel. in a liquid engine, coolant burns white. running an engine at night with short stacks really shows what is going on.
mike nixon

 

[evangilder]

When starting a radial engine, smoke is inevitable, plus radial have a tendency to seep oil. They say if a radial isn't leaving drips on the ground, it's out of oil. Once running though, they should run clean except when running a rich mixture (typical when breaking in an overhauled engine). Inline engines may smoke on startup, but typically do not.

Here is what you get when you start a radial:

If it's had too much prime, or if you have spun the engine too long with a startup, it can result in this:

Now, there is also something used in the airshow world called smoke oil (sometimes called "Holy Smoke Oil"). It is basically a mixture of a fine mineral oil and paraffin, so it doesn't burn, but smokes when mixed with exhaust gasses. It is usually injected into the exhaust manifold. There are a number of different systems out there, and some use less oil, but give you anemic smoke. Then there are others that give a ton of smoke, but don't last as long. I have seen some smoke systems burn through 14 gallons of smoke oil in 15 minutes!).

Rob Harrison makes some really awesome smoke systems. Here is his system on his Zlin in action:

 

[GregP]

In a radial without a dry sump, the oil resides on the crankcase. All cylinders below the oil level have oil on the crankcase side. Even the BEST rings leak evntually, and most cylinders below the center of the radial will get oil in the combustion chamber if the engine sits overnight, or even shorter.

So, if you pull out a radial-powered aircraft that has been sitting for a month or more, you can bet your paycheck that the bottom cylinders have oil in the combustion chamber. It will smoke white when you start the engine until the oil has cleared out and then it starts running smoothly.