Hi
I have just changed my car's oil .The handbook gave the capacity as 8 litres with filter. Done. The dip stick now shows about 1/2 litre too much . Shoud l I drain this off or is there a margin of safety in the handbook stated capacity
thanks
alan
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My handbook gives strong warnings about not overfilling the oil level. I think there is a danger of increasesd pressure causing the seals to fail. I don't know what difference 1/2 litre too much would make, but I would tend to the side of caution and drain the excess.
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Alan,
What on earth takes 8 litres?
David
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Alan, There probably is a small margin over the maximum oil fill but this shouldn't be relied upon.
Overfilling leads to pressure on the crankshaft oil seals and also risks windage, i.e. oil being picked up by the rotating crankshaft and being thrown up the cylinders and everywhere else. The crankshaft does not need to come into contact with the oil for this to happen, being in close proximity is enouigh for the swirling air to pick up oil. I would drain a bit out, perhaps by removing and emptying the oil filter.
David.
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Alan overfilled his engine because he didn't drain all the old oil out. Never take the capacity as the amount you should pour in. Always fill short and only top up when you're sure. (But obviously don't expect garage service departments to be as careful.)
And, Alan, please let us know. What is this monster engine.
HJ
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Hi
Its on a merc c class c240 ( V6). Thank for the advice, A friend has lent me a little oil pump Works off the battery and drains the oil via the dip stick .
Should do the trick
alan
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My Land Cruiser holds 9.2 litres, and 95 litres of fuel!
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Alan,
Its best if you try and keep a fraction under rather than exactly the max dip stick level. MB's particular sensitivities re oil overfilling are to avoid part burn't oil being thrown into your catalytic converter, eventually knackering it over time as a result.
The previous comments are correct re crank seals and windage, but on an engine with a sump capacity of 8 litres, a 1 litre overfill is unlikely to have much influence.
I note that the oil capacity of a 2 litre 93 - 2000, 4 cyl, MB C 200 is 5 .8 litres
The revised engine for end of year 2000 with or without supercharger, now has an oil capacity of 7 litres and the 2.4 litre V6 a capacity of 8 litres.
What oil spec did you use? A quality synthetic starts getting pricey at these volumes.
Regards
Julian
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Remember case of diesel that was overfilled and would not turn off when fuel cutoff. Think it was a HGV and it travelled for some miles with police involved.
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Overfill a diesel with engine oil and it could start running on the sump oil. The only way to stop it then is to grit yuour teeth and deliberately stall it, which means brakes against engine and gearbox and could break something. But it's the only way to stop it because a diesel engine is normally stopped by shutting off the diesel supply, and if the supply is coming from the sump you can't stop it.
HJ
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True, running-on can be a problem with diesel engines -- the oil can reach the intake manifold via the closed-circuit breather system and uncontrollably feed the engine. There is a particular risk with engines in equipment which can be inclined steeply, e.g. earth-movers (diggers) and embankment grass-cutting machinery. There have even been cases of engines momentarily stalling then running in reverse -- not good news on a motorway embankment! Modern diesel engines with this type of breather should have a safety device such as a mercury switch to shut off the engine at high inclinations.
Coming back to the phenomenon known as 'windage' that I described earlier, I forgot to mention that this can cause overheating of the engine as well. Better to be slightly under the maximum oil level mark than too much over it.
David.
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My old Land Rover (Perkins 3.8 diesel) took 9 litres. It had cylinder head problems, and I had to change the oil four times in a fortnight to get rid of water contamination. Cost me a fortune, and I got a serious grilling at the local council tip - I was disposing of so much waste oil, they accused me of running a garage business.
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