1999 w140 m104 I smell oil

[oldsinner111]

1999 w140 m104 I smell oil,no smoke,no oil loss no dripping,however one portion of exhaust has oil sprayed on it.Not ATF.s Smells sometimes when backing up.Been under car with starter change,engine clean.Running sync ATF.Smells like new oil.

[oldsinner111]

One more thing when I changed plugs the 3 rd plug oil leaked around it,did,t hurt the plug. I assume rocker arm cover has O rings or doughnuts to seal all 6 plug holes.

[JohnM.]

Valve cover gasket?

[oldsinner111]

I heard these head gaskets can leak oil,but no oil on engine.Correction oil on exhaust was my fault.Not spraying oil.

[Air&Road]

Yes, the rocker cover can indeed leak oil onto the exhaust. There is a drain back passage that will sometimes leak oil at the passenger side rear of the head to block seam. This is below the exhaust so it should not make a BURNING oil smell.

Have you tried washing the engine then trying to see where the oil is coming from?

[oldsinner111]

It smells like oil,not burnt oil

[oldsinner111]

Now every once in a while a quart will dissapear.Like I can check it everyday and oil level the same then one day a quart gone.Same driving habits.Its like someone is draining a quart out
I change filter and add 2 gallons oil right?when I change oil. Can and where is pcv valve at? and can I be sucking oil into intake

[oldsinner111]

can cheap oil dissapear.That both my car are having oil problems,but I switched from Rotella to Super Tech Wal Mart brand.I just researched the subject,and cheap motor oils can evaporate faster than quality oil.

[glenmore]

Sounds to me like you are not measuring your oil carefully enough.

Try doing it somewhat consistently as to time (after shutdown) and place so you have an accurate idea of how much oil has gone missing.

Also 8 quarts for a change sounds like too much. At 7.5 qts, I am checking the dipstick to make sure I do not add too much oil.

FWIW, on my 2000 C280, 100k, I have a strong oil smell, particularly in an enclosed garage. On inspection, I believe it to be leaking rear main seal with oil splashing on the exhaust.

[oldsinner111]

thanks Glen,you know too,I changed oil yesterday,my dipstick said a quart low before I drained oil.But I over filled my 2 gal oil pan.
So either I'm not waiting long enough for oil to drain down or dipstick is wrong.My book says it hold 8 quarts of oil.

[glenmore]

The capacity may be 8 qts. but you are unlikely to get every bit of the old oil out. Yes, the new filter soaks up some but the only way to tell is have a consistent routine of checking oil level.

In general, no cars like oil overfill, especially Mercedes.