Hi everyone,

I need some help diagnosing a serious oil leak on my Volvo S60 2013 T4.
The engine is the Ford JTJA 1.6 EcoBoost.

The engine originally overheated because of a cooling system failure. After that, both the cylinder head and the engine block were warped, causing oil/coolant mixing.

I removed the engine, stripped it down, and sent both the block and the cylinder head to a machine shop. Both were resurfaced/machined.

After reassembly, I noticed a very significant oil leak from the exhaust manifold gasket area, between the exhaust manifold and the cylinder head. The leak appears to be around cylinder 3.

A few important details:

• All gaskets were replaced with new ones.

• I am sure it is not leaking from the valve cover. I checked several times.

• I have a video showing the oil bubbling/leaking directly from the exhaust manifold gasket area.

• When I press the throttle, the amount of oil leaking increases.

• The oil looks clean, clear, hot, and liquid. It does not look burned.

• I removed the turbocharger and it appears dry, with no signs of oil leakage.

• There is a small amount of oil in the intake manifold, but I am not sure where it is coming from.

• The main heavy leak is definitely external, from the exhaust manifold gasket area. It can create a small puddle within about 2 minutes.

• I suspected valve stem seals, so I replaced all of them, but it made no difference.

• During the machine shop work, the cylinder head valve sealing was checked and appeared to seal properly.

• I also did a basic water/fuel test in the valve chambers myself, and there were no leaks past the valves.

• I honed the cylinders and replaced the piston rings.

• After honing, I measured the cylinders and found that one cylinder, possibly cylinder 2 or 3, had ovality far outside the factory tolerance.

• Despite this, the engine starts, idles, runs, and sounds good.

• This exact leak existed even before I rebuilt the engine, right after the overheating event and before I touched the engine.

• All spark plugs also have black carbon/oily deposits on them, as if the engine is burning oil.

My questions:

Where could this oil be coming from?

Could the cylinder head have a microscopic crack that only leaks under oil pressure while the engine is running?

Could the bad cylinder ovality cause the oil control ring to fail badly enough that oil is being pushed into the exhaust port?

Or is there another possible explanation for oil appearing so heavily at the exhaust manifold gasket area?

Video attached.

I would really appreciate any guidance or ideas on what to check next.

These engines often suffer from a cracked cylinder head after severe overheating. The cracked cylinder head causes oil to leak onto the exhaust manifold which can cause a fire. In most cases the (micro)cracks are barely visible to the bare eye

This is the exact reason why Ford Ford recalled most 1.6 EcoBoost engines in the 17S09 safety recall.


I would start inspecting the cylinder head for cracks

just had another thought about it.


Assembling an engine with an out of round cylinder bore just does not make any sense. Especially not after putting so much money and effort into the engine. Right now the engine is partially rebuild but must still be considered to be terminally ill. The out of round cylinder bore will result in excessive blow-by and increased oil consumption which can result in further problems in the near future.

It is highly likely that the cylinder head is cracked and needs to be replaced. Since the cylinder head needs to be removed anyway for further inspection / pressure testing of the oil passages I strongly suggest to fix this engine properly. This can be done by machining the existing casted sleeves to oversize dimensions and installing oversized pistons and piston rings.

As an alternative the existing casted sleeves can be machined out completely and a set of custom sleeves can be installed. This will make the bottom end much stronger/more durable and also allows to use the existing standard size pistons and piston rings.


Either way after all the money and effort put into this engine you are still facing major costs to finalize the repair.