Oil coming out top of valve cover

I have oil coming out either the oil cap or the gommets where the vent pipe goes into the valve cover. It runs to the back of the engine and collects on the starter. what would cause oil to "blow' out these areas. Could it be a vent, or pvc valve issue. Any thought!!!!
This is a 1976 CJ5 with a 258 engine.

 

PCV system most likely. Bad valve, incorrect plumbing, clogged hoses.

Or just plain old blowby from a worn engine.

Many, many posts on the issue will turn up in a simple search...

 

Plugged oil gallies in the head from years of dirty oil deposits. Especially if you have blow by. You could pull both valve cover and if you find this to be the case take a screw drivers or something and poke into them. Then make sure to flush all the particles down and change oil and filter. I too have an old POS motor and can't wait to get a better one!

 

If I scraped up a bunch of gunk under the valve cover, I'd do more than one oil change to try and clear out the deposits. I'd use a motor oil with a high level of detergent, for example, the diesel motor oils like Delo or Rotella.

Also, these engines are notorious for having leaky valve covers - it's possible (likely?) that much of the oil you see is leaking from the valve cover and not coming out of the oil filler. See this post for my comments on sealing the valve cover. http://www.earlycj5.com/forums/showthread.php?t=56287

If you have a lot of blow-by (ie worn rings) you should see vaporized oil coming out of the filler cap when the engine is warmed up and running. The PCV system should draw out the atomized oil into the manifold to be burned. The connection to the air cleaner is the inlet side - filtered air should come from the air cleaner, go through the crankcase, and be drawn into the cylinders and burned. There should not be a lot of pressure in the crankcase, unless the ring blow-by is making pressure.

 

As I just recently learned (read Tim's last link) incorrect plumbing WILL cause added leaks coming from your valve cover, and PCV grommets.

 

I lost a quart of oil last week trying to pull 3 grand down the highway and keep up with "newer" jeeps. It came out my well sealed oil pan gasket. Turned out my blow by is so bad it overloaded the pcv valve. Temporary solution which works is I have a breather on both valve covers venting to atmosphere. Long term fix is new motor.

 

My 304 in a '76 CJ5 has a slight leak coming from the top of the driver's side valve cover onto the intake manifold....very slight. I have heard that is pretty common for a 32yr old 304, but it's really nothing more than replacing the valve cover gasket when I get around to it or the problem gets worse.