When I installed my new '289' valve covers, I also installed some Fel-Pro blue silicone/steel core gaskets: I was surprised to find oil weeping under every bolt; I sure didn't expect that. So I just installed some old school cork/rubber gaskets; we'll see how that goes. Do you guys have any issues with the silicone gaskets? While I had the covers off, I swapped them side-to-side, for a straighter shot from the PCV to the carb. It just seems so much cleaner than running a tube from the rear of the passenger side cover:
Weird. The silicone/steel is supposed to prevent bolt weeping. But, if you need them sealed and still want the Fel-Pros, when the covers are off, thoroughly clean the bolt holes, then put the gaskets and covers on, and in each hole, squeeze a dollop of RTV black or grey, then install the bolts. Don't worry about it squeezing out from under the bolts, you simply cut around the bolts once the RTV is dry, remove the RTV.
The Fel-Pro ones have a marking for "top" (or Valve cover side) and will leak if upside down, and the bolt holes are too large also. I prefer the Moroso ones for a cast iron head, the factory Ford ones for an aluminum head only. For a hydraulic cam application, the cork Fel-Pro are excellent and will last years if installed dry.
Yeah, I had them installed right side up per the markings. Here's what my buddy Denny said: "Amazing how everything comes new and improved until it fails and you miss the old stuff."
Funny you mention 'upside-down' on valve cover gaskets--I did that very thing on the rubber gasket I put on my first car, several years before I began learning car repair. It was a '78 Fairmont with the 200 I-6, and it's weird how engineers can make a bad decision like that, making a design that's flippable, but it leaks in the wrong way.
I don't understand why a gasket has to be marked this way- couldn't it just be designed & engineered to work in either direction?
Yes, it could, and it should. The Moroso ones are. The Fel-Pro ones are best suited for an aluminum head, because most of them offer a slightly wider valve cover rail than the cast counterparts.
I installed those gaskets in my car and had it leak from the start. Turns out the original bolts were actually bottoming out in the cylinder heads and not fully tightening. I got bolts 1/4 inch shorter and haven't had an issue since. It was weird and hard to diagnose because the washers were snug when torqued but not all the way down and if I put a little pressure on the washers they would move. That is what clued me in as to the issue. Those gaskets are thinner than the stock ones or the rubber ones so it never occurred to me the bolts may be hitting the bottom of the bolt holes.
Me neither. I always assume the factory bolts will be short enough. Also, what about studs and nuts, at least for the two end holes?
I talked to a engine builder who does work for people all over the country, he told me he NEVER uses chrome valve covers because they ALWAYS leak. Only time he puts them on is if the buyer insists on it AFTER he tells them they'll leak.
For chrome and aluminum, I always abrade the metal with a wire brush or wire wheel, then glue the gasket to the cover with yellow monkey snot, by coating each surface to be glued, then letting them air-dry before applying the gasket. It may not stop the leak, but it certainly slows it down
When installing valve covers, I first put studs into all holes, install the gasket and cover, then replace the studs one by one with the bolts, hand tight. This insures that all is lined up correctly. Finally, torque the bolts in sequence. Also agree with the thumbs down on chrome valve covers. Not the chroming itself, but that they are usually thin gauge steel and easily bend or warp.
