Oil from the head? (S4)

[jollyroger]

Hello everybody,

after my last trip with the S4 I put her in the box for a few days, and the first time I took her out for a spin again after two minutes smoke started coming out of one of the engine air vents on the rear bonnet.

I immediately stopped to check what was going on.

It looks like there is an oil leak somewhere in the top part of the head, with a tiny bit of oil dripping down the side of the engine and then running down the exhaust manifold.

When the car starts up and the manifold heats up the oil burns and smokes.

The leak doesn't seem to be very bad, as if I wipe the oil from the parts it takes a long while before I see more oil down the exhaust.

One thing that puzzles me is where the oil is coming from: at first inspection it looks like the leak is not in the head gasket, but rather between the head and the piece of head containing the exhaust camshaft, can this actually happen? Is it bad?

Cheers!

Jollyroger

[matk]

Fairly common as the engine is tilted over at an angle, and if there are any small leaks in the cam cover gaskets , the oil normally goes this way. Could also be this......

http://www.lotusespritworld.com/EGuides/EM...haft_Oring.html

[910Esprit]

Very common on early models with the saddle type cam covers, less so on later models.

Its bad in the sense that you need to remove the exhaust cam tower and all that entails (removal of cam belt, checking the valve clearances etc.). However its nothing to worry about as far as using the car is concerned. If it doesn't get any worse, you could choose to ignore it until your next C service is due, but it makes your car look like a dog iin the meantime...

cheers Steve

[jollyroger]

Thank you for the tips guys!

Is there a way I can verify mre accurately where the oil comes from?

Would it possible for it to come out of the head gasket? I have looked carefully and it doesn't seem to be the case but...

Cheers!

Jollyroger

[910Esprit]

I suspect you have already correctly diagnosed your problem! Its unlikely to be the head gasket leaking oil, as there is only one point oil passes from the block to the head and this has a 'rubber' (viton) seal. (and the head gasket is below the exhaust manifold)

However. the joint between the head and the 'cam tower' is literally full to the brim of oil and can fail. Thats probably where the oil is coming from. Although. as Mat says, check its not simply coming from the cap at the end of the exhaust camshaft. (may simply be worth doing this as it costs virtually nothing).

To diagnose it properly you will need to get rid of all the existing oil and observe where it is coming from.

NB Under no circumstances be tempted to simply tighten the bolts securing the cam tower, or you are likely to compound your problem.

Steve

[matk]

Try sprinkling a LIGHT coating of talcum powder over the affected area and leave it overnight. It should be easy to see the trail the leaking oil makes, and follow it back to source. A bit more detail, when running oil collects in the top of the cam towers. Because the engine is canted over, when you switch off, not all the oil can drain back down the engine, and consequently if there's a gasket leak, there is plenty of opportunity for the oil to seep through. In cars where the engine is mounted truly vertically, the oil flows straight back down after switch off and you tend not to get this problem.

Its really not a biggie, unless of course the leak really worsens.

[jollyroger]

Guys thanks a lot!

The problem manifested itself after a long trip of about 1000 Km in two days.

I had everything checked before departure so the problem came to be while on the trip, likely due to the many Kms travelled.

I haven't pushed the car much during the trip, but could it be that some of the screws on the cam towers loosened up a bit?

As you say I am NOT going to tighten anything just to try something, as I could make it worse, but I am wondering whether the vibrations on the long run might have loosened something...

Cheers!!

Jollyroger

[Paul C]

However. the joint between the head and the 'cam tower' is literally full to the brim of oil and can fail.

bang on.

Can fail:

1, By leaking oil into the sparkplug wells and filling them up.

2, by slowly dropping oil onto the manifold so smoke comes from the engine

air vents as the manifold heats up the oil burns and smokes until it's gone.

So common that i thought nothing of it buying an esprit with it and getting fixed

straight after. If you are due a C service and valve shim checking etc, then thats the

time to get it sorted, as most of the stuff needed to be in bits to do the job, is in bits.