Oil Leaking From the Exhaust Manifold and EGR Cooler

[1979 FJ40ish]

I have a 1979 FJ 40 with the original 2F engine, approximately 125,000 miles and federal emission intact.

It recently started to smoke heavily for about 10 to 15 minutes on startup after sitting overnight, and it is also leaking black oil out of the exhaust manifold and the EGR Cooler. A lot of oil. I can see it drip out of the FJ while it is running.

Attached is a diagram indicating where the oil is leaking from. I have done everything I can to confirm the source. It is not leaking from the valve cover gasket, nor the head or manifold gaskets.

In addition to leaking at the joint indicating oil is running down the EGR pipe into the EGR Cooler and then leaking out of the cooler.

A dry compression test on a warm engine yielded the following: cy 1 – 135, cy 2 – 130, cy 3 – 135, cy 4 – 135, cy 5 – 135, and cy 6 – 140.

I changed the PCV valve after this problem started.

The engine runs okay and does not overheat.

How can oil get into the exhaust manifold?

 

[charliemeyer007]

Interesting. Valve stem seals worn out or came loose, clogged oil control rings.

 

[pb4ugo]

As Charlie said, its probably valve seals. Overnight oil passes thru the seal and leaks into the cylinder.

 

[1979 FJ40ish]

Would valve stem seals explain the oil in the manifold?

 

[charliemeyer007]

Exhaust valve seal will leak into the exhaust manifold, intake leaks into combustion chamber and causes smoke in the exhaust.

How much blow by is present.

 

[1979 FJ40ish]

I don’t know what you mean by blow by? Please explain.

 

[charliemeyer007]

Your compression #'s are OK. Blow by is compression leaking past the piston rings. Engine idling, loosen oil fil cap completely, it should just sit there, not hop around. You can remove the cap, and place your hand over the hole, you should feel a little pressure