dear All, My 280 ce has recently been blowing smoke, mostly on start up when
warm, and after idling at the lights. It also blows a "bit" when driving.
i have had the valve guide seals replaced, but this made little difference.
I would like to do a compression test on the car and am wondering if anyone
has the magic figures that the car "should" be. I am presumably looking at a
head rebuild, or worse ring replacement.
Although I can't give you MB's 'official' figures, you should be getting in
the order of 150-180 psi, with no more than 10 psi difference between the
cylinders. Test with spark plugs removed and throttle wide open. Crank for
5-10 seconds, and don't forget to reset the gauge after each cylinder!!!
Before starting down the long road to an engine rebuild I suggest you
check the crankcase ventilation system to ensure that oil isn't being
blown into the intake manifold.
The short hose from the valve cover to the intake should be clear and
not spitting oil while the engine is running. Remove it to test that. If
it's spitting oil, you need to remove the valve cover and clean out the
oil baffle inside the cover for its function is to allow the oil to
separate from the crankcase fumes and so allow the oil to drip back into
the cam area. A cold running engine - either very short trips or
defective thermostat - contributes to cause this sludge blockage.
I just happened to have a picture of the tube, but unfortunately not the
valve cover with the oil baffle.
Check at http://w123.homepage.dk/cranckcase_ventilation.htm
Just wondering what function the small tube, connecting to the black rubber
hose, is good for ?
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