After an engine-out top end refresh - replace sodium exhaust valves, all gaskets and seals, new hoses, etc. Documented here: https://www.ferrarichat.com/forum/threads/observations-on-a-gt4-engine-pull.458208/ My sons and I finally started the 308GT4 this past weekend. Started instantly on the first click of the starter with an eyeball tuneup: No leaks anywhere, fuel, coolant, vacuum, except for a small leak at the rear bank exhaust cam seal (where the air pump pulley goes). Upon close examination the cause of the leak was immediately apparent: The valve cover gasket was a little too big and distorted the seal. Look at the 10:00 o'clock and 4:00 o'clock positions on this photo - the gasket is green. The distortion is most pronounced at the 10:00 o'clock position. The gasket pushed the outside of the seal in, made it oblong, and opened up a gap on the inside where the oil leaked out. The seal popped right off and you can see where the gasket is in the seating surface a couple of mm. The seal itself is fine, all I have to do is trim that gasket and tap it back in and it should be OK, but I ordered a couple of new ones anyway. It's a pretty standard 56 x 40 x 7 mm seal. Available here for $3.75 each: http://www.oringsandmore.com/oil-shaft-seal-40-x-56-x-7mm-double-lip-price-for-1-pc/ The point I'm making is that if any of your camshaft seals are leaking check the gasket where the cam cover attaches to the head. Unless that gasket is trimmed carefully it might be the source of your problem. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
You trim that gasket so that it fits the seal.... before you install the seal. Bet you won't make that mistake next time.