My valve cover cap was leaking, but not primarily from the vent hole. It was leaking from the rubber seal under the cap. IE: the oil splashed up and the rubber seal would not hold it in. So I added another layer of rubber. It really slowed down the leak. Jerry

I had a weird "oil" leak from my fresh motor last week. It showed up as a coating, spray and large drops starting from the front (bottom) of the engine / trans back to the shift housing. I even found drops of oil on top of the starter. I have less than 100 miles on a complete resto—everything under there is clean & shinny, so I figured I'd spot the source right away. Nothing... except for an outboard CV joint boot flopping around and flinging grease everywhere. I repaired the boot and the "leak" went away.

I know there's a big difference between oil and grease, but this stuff looked and behaved like motor oil. I can only guess that when the thick grease contacted hot surfaces, its viscosity lowered resembling oil. My ceramic coated headers were a mess! Color was no help; my oil's green and my CV grease is green. 

Cup Cake- It does. And its clear.

jedduh- Its is predomintly on the clutch side but is top to bottom. I'm going to replace a brittle valve cover gasket cuz its smoking the manifold but it seems that I get oil all over the front of the engine near dipstick and dizzy as well as the bottom of the bell housing. I've cleaned it once to try and isolate while the car is stationary but it only appears after a drive to work and back (about 12mi). No amount of running in the driveway gets it to appear. Its really making a mess out of the bottom of the car.

When I did the swap I installed new axle seals as well as the rod change oil leak kit. I never unsealed the motor with fear of screwing up the flow of chi

Which seems to be my MO...lol

The interior of the motor is at high pressure so oil blows out of the cap and every where really. If the cap is the only vent its not enough whether you have blow-by or not. I think a 998 should normally have  a vent on the tappet chest cover as well. 

 

When do you think that GOLD Seal was actually assembled? My best guess would have to be back in the 70's or 80's . When you installed the motor to you freshen the exterior seals? Including the Crank Shaft Seal - or the front cam cover and cam seals.and new axle seals + shift shaft seal (dependin on your setup.

If the motor sat a long time- and was put right into service- there is good chance Gold seal seals are "loose" or lost their elasticity to hold the oil in.

Does it leak oil in certain spots when parked? 

WOrking on a friends 998-freshening up the fuel  tuning etc- it sits alot-- Now after 1 week of driving.. HUGE New Oil leak   - Rear main BOO- Get to take all that apart this weekend.  

Seems like I can't win. I bought a gold seal A+ 998 motor last december. Runs great but I keep getting oil leaks all over. I've been noticing a mist on top of the valve cover. Pulled my vented cap and blew into it from the bottom. Bunch of oil came out. I've got a tappet cover breather plumbed to the air box and the vacuum port plugged. Correct me if I'm wrong but shouldn't air enter the cap and vent through the canister? When I first got it I did a comp test and want to say it was somwhere near 170 on all cylinders. I'm thinking about adding a pcv and connect to the vac port to get some negative pressure to help it and see where that goes. I'm also going to take it to work where their are professional mechanics and no harbor freight tools anywhere to get more accurate comp and leakdown results. Seems like I shouldn't have these problems on a fresh engine. I know minis leak a little oil but my underside is COATED!