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I am getting a small amount of oil coming through a couple acorn nuts as shown on my valve covers below. Anyone know what torque may be needed on these acorn bolts? I tightened them a little more, somewhat snug (maybe 5-10 lb or so, ball park estimate, finger wrench turn) but still have a little oil after a real long run. Also, on a couple of other bolts, I discovered they will not tighten further either, as I keep wrenching on them to snug, and it seems I keep turning the wrench but doesn't enhance the tightness. I am not wrenching on them hard, so I am sure I didn't strip anything...those two bolts are just snug, but won't go tighter. It would be nice to know what the torque should be, as maybe I need to go a little more with the wrench. I understand these are pretty expensive covers and would not like to break anything, which is why I have been conservative in the wrenching.


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Originally posted by LIV1S:
Just making sure you catch that the torque rating is in INCH-POUNDS not FOOT-POUNDS.... BIG DIFFERENCE. Smiler

Damn, thanks for the warning. I thought the 70 seemed pretty high, as that is about wheel torque strength. I guess I will need to get an inch-lb torque wrench. O-rings may help too I suppose as PanteraDoug suggests. Maybe I should just take one acorn off and see what things look like under there.
I know I have seen listed acorn nuts with builr in orings on the bottom. I have a set of these have never run them yet but I could tell when I got them they leaked around the bushings under the nuts. I was going to have a groove cut into the bushings to accept a oring. This with the oringed acorn nuts should stop all leaks.
...I wouldn't use Rubber 'O' Rings!!
'O' Rings need a 'O' Ring 'Groove'! Otherwise there is NO place for the Rubber to Go...The rubber will 'crush-out' and tear!

The 'Dowty Seal' Will work!

I would use Thin 'Fiber' Washers UNDER the Existing Steel Washers! They will take the Torque and Won't Tear! They will seal up that Oil Leak!...
Last edited by marlinjack
Here’s the installation instruction from Ford. It might be a bit hard to read but I cant upload a high resolution copy. The 65-70ft-lbs mentioned above would be consistent with the torque for installing the studs in the head (not acorns). 70-75 in-lbs (about 6 ft-lbs) is the torque called out for the acorn nuts. The 65 in-lb call out is actually for the ¼-20 valve cover mounts to the head. The hardware stack beneath the acorn nut was a soft copper washer and an aluminum spherical washer (flat on one side spherical on the other). The Dowty washer would work fine for replacing the copper washer provided you can find one with a 7/16 ID and an OD small enough to clear the well, but the spherical washer is still a potential source of leakage, thus the instructions call for applying a small amount of RTV to the spherical side. Be advised, the original acorn nuts also had a nylon insert that made them a locking fastener of sorts.

The most common source of leakage is from the use of thick valve cover gaskets that can take a compression set. When this happens, the torque applied to the acorn nuts is lost and they leak. The instructions refer to the valve cover gasket as a “special gasket”. It’s .060” thick and made from ordinary paper/fiberous gasket material, but they are relatively resistant to taking a compression set compare to typical cork or neoprene gaskets.

In practice, the acorn nuts apply more force to the valve cover gasket than the ¼-20 mounting screws do.

Jan, yours appear to have thicker aftermarket gaskets. If they were relatively sealed before, merely re-torquing the acorn nuts may do the trick if they have merely taken a little set. If your ¼-20 screws are also loose, that would also point to the gaskets having relaxed a bit.
I note earlier remarks in the thread about these being made from poor quality materials incapable of being polished. Though I cannot speak for all of production, I’ve had about a dozen sets of these through my hands and have not found that to be the case. I have seen several polished sets that actually looked pretty good and have also welded and seen many welded mods to them, usually adapting breathers to them. The ones I’ve welded received weld quite nicely. The studs are actually quite nice in quality but hard to come by.

I have never actually seen a cracked set from over tightening as Doug mentions but can well imagine 60-70 ft-lbs on each acorn nut would likely do that. I’ve actually found the valve cover itself to be pretty stout.

Lastly, as for them being a PITA to use, I didn’t really find them any more so than other stud girdles, although for real racing gear, I’d rather apply the girdle independent of the valve cover so lash can be checked after the girdle is tightened.

You must admit though, the fangle factor is quite high.



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The point of the cork gasket being a problem is a good one.
Why can't the covers be set in just RTV without the gaskets?
Can't get any firmer then that.

The Boss 302 gaskets would always develope leaks and the way I fixed that was to get rid of the gaskets and RTV them, in Blue, close enough to Ford Blue.

RTV on the aluminum washer insert too. Should do it.

Kelly, you have to see the crap I have run across as far as poor installation. It just takes one idiot with an impact wrench and whamo.
Trust me, you can break them, and no, it wasn't me with the impact wrench. That person is listed as missing and I know the body will never be found. Smiler

The set I had was as out of the box, black wrinkle.

The crack about the covers polishing like crap is from Mr. Chromed Nuts himself, Gary Hall. You had to hear him moan about them? Trust me.

I do not presume that all the castings were made the same way either, as far as materials.

I never welded on them, so I can't confirm or deny that.

I can say, don't loose the acorn nuts or the studs. Those you will have to buy another complete set to get a replacement.
Originally posted by Cowboy from Hell:

The owner of the Clevelands Forever Forum wrote and asked me to tell you he has the same valve covers, when his started leaking "I used black rtv and they don't leak there anymore, just where my cork gasket kicked out a bit...". He also asked me to give you this link to information on the Clevelands Forever wetpaint wiki

Ford Motorsports Valve Covers


Thanks, as I was thinking of trying a little RTV on the acorn nut washers, and see what happens as a simple solution first. But just want to be clear I am only talking about a slight leak on a couple of the acorns, and not the valve cover gasket itself. Probably a good time to get me a small torque wrench and get the acorns on the right torque too. Probably the normal Joe wouldn't even notice the leak, but anal me sees that type of therapist knows Smiler
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