[W126 Coupe] My 500 SEC smoke when car down a inclined street

[Dick Spellman]

Christophe Welcome!

If you can, check the compression wet and dry on all 8 cylinders to 
confirm what is most likely worn valve seals and/or valve guides.  It 
would seem unlikely that the oil rings on the pistons would be the 
problem on your engine.  Much more likely that it is the valve 
seals/guides.  A less accurate method of assessing what is going on with 
the engine would be to answer these few questions.
What grade/viscosity oil are you using?
What is the oil/filter change interval you are using?
What color is the smoke?
Are you consuming oil?
Are you consuming anti-freeze?

Regards,

Dick

cbcad at free.fr wrote:

>Hello to mbcoupe,
>I'm Christophe from France and I own a 1987 500SEC in France. This car runs
>great but since some month when I drive it on a inclined road (when car goes
>down), some oil is burned in exhaust system and it smokes a lot of at rear
>exhaust pipe ! When you drive it on a horizontal road, all is good. It's the
>same thing if the car is parked with front down when I start it, it smoke a lot
>for few minutes.
>All engine runs good but I don't know if oil goes directly to exhaust manifold,
>or intake manifold and is burned as gas, or maybe a valve problem, or maybe a
>anti-pollution system fault, etc....
>Someone can help me because I'm very sorry to see my MB coupe like that.
>I hope it's not a big problem, next week I'll change oil and oil filter to see
>if it change something.
>Please can you advise me.
>Sincerely
>Christophe
>
>PS: How can I join the members's car list ?
>
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