High pressure under Valve Cover
 

I just replaced the oil filler cap on my 1985 190e 2.3. The old one had a hardened seal. Oil was leaking out from around it. When my father saw it happen, he said that oil is pumping out with a lot of pressure. Too much pressure.

What could be causing that much pressure under the valve cover?

Worn cylinders, pistons and rings.

Good luck,

Blowby
 

Do a compression check on all cylinders, its most likely that the compression rings in one or maybe more cylinders has had it

Check and make sure the egr system is working and the lines aren't plugged with deposits.

That's what he said would take care of it (egr). But if I remember the 190e correctly, there is no PCV valve.

Jim

When the oil cap seal gets hard and no longer seals, you can lose a lot of oil. I was losing a fair quantity on the 4.5 until I replace the seal. FastLane and PartsShop sell the seals for about $.30, much cheaper than a new cap. Blowby will greatly increase the rate of loss. How many miles on your car?

167,000 very low mileage. We replaced the valve cover gasket right after I bought it (two years ago). I bought it at 148,000. It was owned by an older lady and was used as her daily driver until the tranny went.

My father was vry impressed when he removed the valve cover and saw how well the engine was run in. It was very clean.

Jim

Already grabbed a new cap from the dealer. It was the bigger knobbier kind like the one on my 300D. The old one was very difficult to remove.

Whether it has a pcv valve or not, the egr passages can get clogged with deposits over time, precluding pressure relief the egr system affords. This can be hard on anything that seals oil on the engine.