I have NO trouble with mine....once I figured out how to seal it properly. Here is how I do it.
1. Clean everything...making sure to get all oil off.
2. Run a 1/4" bead of RTV gasket silicon around the mating surface of the valve cover.
3. Allow it to dry for about 1 hour, or until the surface is not taky but the silicon is still soft underneath.
4. Place on head and gently snug down. DO NOT Tighten bolts. You want it seated all the way around but not so much that silicon squirts out.
5. Let sit overnight. If you try to start it up before then...it will leak.
6. Next morning, tighten down the bolts.
This method works for me each time.
John......southern CA
84CJ7, 3"lift, 32"BFG, 4.10's, ARB Locker, Solid Axle's, Durabak