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Stan, Mercedes Technician
Category: Mercedes
Satisfied Customers: 3526
Experience:  Technical support engineer
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I have a problem with my mercedes c230 kompressor recently

Resolved Question:

I have a problem with my mercedes c230 kompressor recently had major job on engine due to tensioner failing and smashing valves. Now the problem I have is that before and after I had this job repaired (head done, valves repalced, water pump, new chains, decoked, piston rings, etc) I was losing alot of oil. basically I would fill to about maximum and then drive. 250 miles latter oil has leaked from engine. there are slight puffs of black smoke from the exhaust, but the mechanic cannot figure it out and he says there are no leaks. Help.

Submitted: 1 year ago.
Category: Mercedes
Expert:  Shantal-Mod replied 1 year ago.
I'm Shantal and I'm a moderator for this topic.
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Customer: replied 1 year ago.


I still have not found an answer.

What happens if I close the question, do I get a full refund.



Expert:  Stan replied 1 year ago.
Hello Omar,
If the engine is getting oil through the engine breathing, whole intake should be full of oil.
If not, please have the spark plugs checked. If intake is clean, but spark plugs have the deposits- it will indicate that engine mechanical components are to blame.
Also combustion chamber leakdown test must be carried out.
Unfortunately it is not possible to check the valve stem seals without rempving the camshafts, valve stem seals and valve springs. Their conition is determined by measuring the valve play in the valve stem.
Big wear of the cylinder wall will cause too big of a play for the pistons, and even with the new rings, there will be oil consumption.

Best regards,
Customer: replied 1 year ago.

Hi Stan,

What do you mean by engine breathing, and when you say intake can you be a bit more spcific.

Is combustion chamber leakdown test somthing most garges can carry out or somthing that mercedes themslves do.

Given that you say that the engine will still consume oil, do you think that drinking 4-5 liters of oil within 250 miles is very excessive.



Expert:  Stan replied 1 year ago.
there are lines from crankcase connected to the intake hoses to reduce the crankcase pressure. This air from crankcase and valve covers goes through oil separators and back into the engine. If this system does not work properly, oil will be consumed with fresh air.
So please have the throttle valve, mass airflow sensor and the intake manifold checked for oil residues.
1 liter of oil per 700 miles is considered to be maximum normal consumption. So the oil consumption in this case is way too high.

Not all of the garages do a leakdown test. Usually they check the compression.
Stan, Mercedes Technician
Category: Mercedes
Satisfied Customers: 3526
Experience: Technical support engineer
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