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Head gasket leaking oil

So i have a 2012 Mercedes Benz C250 1.8 cgi I noticed that my head gasket is leaking oil car is not over heating took or mixing coolant with oil is this a common issue ??? Should I be worried

Retorquing the head bolts took care of that problem on my 1984 Chevy Cavalier’s 2.0 L engine.

@shanonia gonna give it a shot before dishing out cash to replace the head gasket

Are you sure it is your head gasket and not your valve cover gasket that you are describing? Sorry, I have to ask these questions round here. Both of these items can leak oil obviously, so if you would post a picture or two it would clarify the matter greatly and more accurately aim peoples advice. Valve cover gaskets leaks are much more common than Head Gasket problems, though neither is outside the realm of possibility.

A picture or two would really help us help you here…


Good point above. And if it’s a valve cover gasket, be aware the torque for those bolts is usually expressed in inch-pounds. You don’t want to turn them that many foot-pounds.

Initially I thought it was the valve cover also so I removed everything engine cover heat shield etc. and ran a UV dye in the engine oil drove about 200 miles no leak booom leak comes back nothing around the valve cover nothing around vacuum pump just seepage from head gasket let me try to post pictures noob on here

Step 1 - First Steps

The very first thing to do is to disconnect the negative battery terminal. This will ensure that you don’t suffer an electric shock when you replace the blown head gasket. With a drain pan in place underneath, open the valve and drain the radiator. Don’t let the coolant drain into the ground because it can be toxic. Instead, store the coolant in a sealed container and dispose of it responsibly.

Step 2 - Accessing the Gasket

Using wrenches, loosen all relevant bolts and remove the intake hose and the air box. Next, you’ll need to take off the compressor for the air conditioner. To do this, you’ll have to remove several bolts and when the compressor is free, lay it on it’s side to give you access to the cylinder head.

With a screwdriver, loosen the clamp on the water pump hose and remove it. With this done, you can now get to the alternator. You don’t need to take off the entire alternator harness. Simply remove the bolts and lay the alternator on the radiator hoses so it’s out of the way. Disconnect all the lines that run to the air conditioner. You will now be able to fully access the cylinder head.

Step 3 - Removing the Cylinder Head

Open your service manual and pay close attention to the tightening sequence for the head bolts that hold the cylinder head in place. These are very specific and need to be loosened in the correct reverse sequence.

Step 4 - New Gasket

Remove the old blown head gasket and fully clean the cylinder head so the new gasket will sit cleanly on the metal. Put the cylinder head on top and tighten the bolts in the correct sequence. You’ll need to use a torque wrench for this job as the bolts need to be at a specific pressure which will vary from vehicle to vehicle. It’s vital that you do this properly or you’ll just find yourself with another blow head gasket.

Step 5 - Replace Components

Replace the components and reconnect the hoses in the order in which you disconnected them. Ensure that the alternator is tight enough to run as it should. Once everything has been tightly connected, fill with fresh coolant in a mixture of 50 per cent coolant and 50 per cent distilled water. Turn on the engine and allow it to idle until it reaches operating temperature. Leave to run for several minutes then switch off and check the coolant level and for any leaks.

Gee Donna, I didn’t realize it was that simple .

I’m wondering if Donna is one of those people that gets paid to post very vague diy instructions on other websites

Why am I saying that?

Because her advice WAS very vague

nothing Benz specific at all

no torque specs

no bolt tightening diagram


Her advice could have applied to ANY vehicle

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Just like all of the other posts by Donna .

Except an over-head cam engine. Not sure if this engine is. If it is, then you have to handle the timing belt or chain. Depending on vehicle - that can get tricky.

Before retorquing the head bolts, find out first if they’re torque-to-yield head bolts.

Because if they are, retorquing them can stretch the head bolts to a point where they lose their clamping force. And that can make matters worse.


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You make sound so easy :roll_eyes:

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Also… If it is your cylinder head gasket and you are diving into that repair… Be certain that you take the head to a machine shop to make sure it is square…it has to be in order to seal correctly. If the shop finds any warpage the will deck the head for you to level everything off in terms of “squareness”. This is not really an optional step…if it needs to be cut…it needs to be cut. The machine shop will be able to do that check for you and tell you what is what. No point doing the head gasket if you have a warped cylinder head.

As a DIYer, I wouldn’t touch A/C lines as I have no way to collect the refrigerant…(ya know in addition to all of the other so completely general directions you like to give…:face_with_raised_eyebrow::face_with_raised_eyebrow:)

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