Ok, So far I'm loving my new 350 and 6 speed (1200 miles or so on them) except for the persistent oil leak out of the engine. I am almost 100% positive it is the passenger side valve cover. I've replaced my cheesy chrome valve covers with cast aluminum ones. I've tried Fel Pro Perma Dry Plus gaskets, and right now I've got the extra thick cork gaskets on it. It's STILL leaking out the rear corner of the passenger side valve cover!!! It's really frustrating me! I don't know what else to do. If anyone has any suggestions whatsoever I'd love to hear them! I'm going to go back over checking the distributor gasket and the oil pressure sending unit again just to make sure that they're not the culprits, but I know I can feel oil around the back corner of that valve cover and I don't feel it above there on the engine, so I'm pretty sure it's the valve cover. I've also got a smaller leak out of the fuel pump mounting plate, but I'm not so worried about that as the valve cover. It's really getting to me. If anyone has any suggestions please let me know!!! Thanks so much!!

-Paul

 

The valve cover gaskets are pretty easy to replace. I'd recommend using the rubber variety (got mine from NAPA). They are a lot easier to finagle through all of the various wires, hoses and whatnot without fear of tearing them up. You can also use a little more torque on the bolts without isssue.

I just swapped mine out and got rid of a nasty oil leak. My pvc works a lot better as well.

 

Thanks for the reply! I've swapped the gaskets several times so changing them is not an issue at all. I do have a set of the rubber gaskets, but I haven't tried them with the new cast aluminum valve covers I have now. I know they leaked with the old stamped steel covers. I've also tried the Perma Dry Plus gaskets which are rubber over a hard plastic frame. Those leaked also So anyway, I guess I might try the rubber ones with the new valve covers. Any other suggestions?

-Paul

 

Any interference with the valve covers and the heads?? I had that problem on my engine swap.

 

also put a bead of silicon RVT stuff around the valve cover where the gasket would go just for added security. i do that on my car and dont have any leaks, when i used the crappy cork gaskets and id tighten them alittle to much it would split the gasket, but try the new rubber gaskets and some rvt around the valve cover.

 

How about, take it to the quarter car wash along with a can of Gunk Engine Bright or other similar (diesel fuel in a spray can) engine degreaser; sterilize the engine; see where the oil is actually coming from; and direct your efforts there. The "maybe it's this, maybe it's that" approach is a little too much like work for someone like me.

You might find it's not the VC at all.

 

Thanks for the advice guys, all of it is very much appreciated! I will put some RTV or maybe some of the 3M weatherstrip adhesive on the gasket to mate it to the VC (I've been told weatherstrip adhesive "gorilla snot" is great for this purpose lol) I am pretty sure it's the VC because I've been on my back under the car (and standing under it with it on a lift) and I can see oil coming from the corner of the VC but not anywhere above that point. Then the oil runs down the block, over the starter and down to the bottom of the bellhousing (freaked me out at first thinking I had a rear main leak out of my brand new engine ) Anyway, I am going to double check all the other trouble spots as well as try and re seal the VC gasket again. I'll keep you posted, and keep the suggestions coming! Thanks again!!!

-Paul

 

If its one of the 'top' corners, it could also very easily be an intake manifold leak.

 

Nope, I'm pretty sure it's the bottom corner, but I'm gonna check the intake too to make sure....I've just gotta get out in the garage and climb around on the engine and see. I'm pretty sure that it's the bottom rear corner of the passenger side valve cover. The driver's side leaked too, but I've got that sealed up now, it's just the passenger side, but like I said I'm gonna double check all the common trouble spots again when I get out to the garage again (hopefully this weekend). Thanks again guys!!

-Paul