blue smoke

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catman4115

New Member

Sep 9, 2005

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Rhode Island

Sep 18, 2005

#1

• Sep 18, 2005

• #1

i was wondering my car blows out a little blue smoke when I get on it. It seems like this has been happining reciently when I put my exhaust on ( i have shorty headers, an h- pipe w/o cats and flowmaster cat back) I thought it might be valve seals but my oil pressure is fine. Any imput would be greatly apriciater. Thanks

 

RsStanG1987

I shaved all my pubes playing this game.

10 Year Member

Mar 13, 2004

569

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79

Dupont PA

Sep 18, 2005

#2

• Sep 18, 2005

• #2

I think maybe your car is running i think thats what blue smoke means. I may be wrong..

 

Foxfan88

My Grandpa has great wood.

Sep 13, 2004

2,487

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Miami, Ok

Sep 18, 2005

#3

• Sep 18, 2005

• #3

RsStanG1987 said:

I think maybe your car is running i think thats what blue smoke means. I may be wrong..

Click to expand...

did you mean to say rich??

 

Anthony85stang

New Member

Sep 8, 2005

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Meriden, CT

Sep 18, 2005

#4

• Sep 18, 2005

• #4

Blue smoke is a sign of burning oil. The valve seals could be leaking but it wont affect your oil pressure. If it doesnt smoke real bad and you arent having to add oil i wouldnt really worry about it.

 

Michael Yount

Mustang Master

Apr 10, 2002

9,039

6

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Charlotte, NC

Sep 18, 2005

#5

• Sep 18, 2005

• #5

Black or grey smoke = rich; the blacker, the richer

Excessive white vapor = coolant in the combustion chamber (leaking gasket or cracked component)

Blue smoke = burning oil; on acceleration usually rings; on deceleration or start up usually valve seals/guides

 

ninety15.0

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Mar 10, 2004

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Sep 19, 2005

#6

• Sep 19, 2005

• #6

How much is it? can you actually see the smoke out the rear window when you get on it, or is it something someone else may have noticed? does it smoke at idle? how much oil are you down between changes?

 

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catman4115

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Sep 9, 2005

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Rhode Island

Sep 19, 2005

#7

• Sep 19, 2005

• #7

its not that much, my friend said he saw it when he was behind me, i mean i dont see anything out my rear view mirror, but sometimes when i come to a light a little will pass by my window. it doesnt do it at idel, only when i get on it

 

Michael Yount

Mustang Master

Apr 10, 2002

9,039

6

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Charlotte, NC

Sep 19, 2005

#8

• Sep 19, 2005

• #8

You say some drifts by when you come to a light - sounds like it's smoking on deceleration too....

 

srothfuss

Last night I stabbed the same guy 7 times in a row

Oct 17, 2004

1,796

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Woodward Ave.

Sep 19, 2005

#9

• Sep 19, 2005

• #9

How many miles are on your motor? Do you drive it really hard?

Forged interals in the 5.0L engine require more cleance between the cylinder walls / rings. Most people see a small puff of smoke when they are shifting from 6,000RPM. To me it sounds like you should start saving for rebuild...

 

Michael Yount

Mustang Master

Apr 10, 2002

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Charlotte, NC

Sep 19, 2005

#10

• Sep 19, 2005

• #10

The extra clearance is required because of the different rates of thermal expansion of the cast iron block and the forged alum. piston. Once the motor is warm, the cylinder should seal up pretty nicely. Unless, of course, it's just time to do something about a tired motor....

catman - how many miles on this beast?

 

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catman4115

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Sep 9, 2005

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Rhode Island

Sep 19, 2005

#11

• Sep 19, 2005

• #11

theres about 92k on the motor and its stock. I dont beat it that hard, but i do like to get on it once and a while.

 

feifong

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Apr 4, 2005

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mesa

Sep 19, 2005

#12

• Sep 19, 2005

• #12

sounds like my 83 after freeway driving i get a big puff of smoke i see on my left hand side window. Im thinking its the valve seals though.

 

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catman4115

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Sep 9, 2005

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Sep 19, 2005

#13

• Sep 19, 2005

• #13

i dont think its valve seals because my oil pressuse is fine. my other mustang had valve seal problems and the oil pressure would drop extremely low when ideling and blow out a cloud of blue smoke

 

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tjm73

Founding Member

Aug 3, 2000

2,418

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Rush, NY

Sep 19, 2005

#14

• Sep 19, 2005

• #14

Michael Yount said:

Black or grey smoke = rich; the blacker, the richer

Excessive white vapor = coolant in the combustion chamber (leaking gasket or cracked component)

Blue smoke = burning oil; on acceleration usually rings; on deceleration or start up usually valve seals/guides

Click to expand...

What a great little nugget of knowledge... thanks. I've never heard that before. I mean I know what the smoke colors indicate, but not to that level. I never thought about accel. and decel. indicating different problems.

 

Michael Yount

Mustang Master

Apr 10, 2002

9,039

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Charlotte, NC

Sep 19, 2005

#15

• Sep 19, 2005

• #15

catman - you can have oil pressure that's just fine, and valve seals/guides leaking like crazy. The two things don't have to be related.

Best thing to do is have someone follow you and tell you what it's doing. You can't tell from inside the car nearly as well. Put in 2nd gear and accelerate hard from about 2000-5000 rpm, and then let off the gas (be sure the guy following knows what you're gonna do). He can tell you if it's smoking on acceleration or deceleration or both.

Cranking compression and cylinder leak down tests will confirm cylinder seal and give you more detail on where the problem exists.

 

chobracobra

New Member

Jun 29, 2004

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jersey shore

Sep 19, 2005

#16

• Sep 19, 2005

• #16

If a compression test is done, what numbers will indicate leaking rings? Also what exactly is a leakdown test?

 

Michael Yount

Mustang Master

Apr 10, 2002

9,039

6

79

Charlotte, NC

Sep 19, 2005

#17

• Sep 19, 2005

• #17

There's a device that screws into the spark plug hole, and a source of compressed air. A set of gauges read the pressure of the source vs. the pressure the cylinder is able to maintain. A certain % drop between the two indicates how well the cylinder is holding pressure. You perform the test with the piston at TDC (unless you don't mind getting run over by the car or spinning the engine) on the compression stroke (both valves closed). If the shop/equipment (compressor remotely located) is quiet enough you can listen at various places to see where the air is leaking. Noise in the tailpipe usually means air is making it past a burnt or bent exhaust valve; noise in the intake track usually means a bent intake; noise through the oil filler (crankcase) means air leaking past the rings.

The leak down test is often performed after a cranking compression test is run on all 8 cylinders. If a particular cylinder is more than about 15% low from the rest, it's a candidate for the leakdown test.

Catman - how much oil do you add between changes? How far between quarts?