The more you look the more you find...
 

SO it is when you geting to know a "new" old car and so it is with the 81 SC I got a couple months ago.

Thus far it runs stong, no smoke or any major leaks etc. An item that I had noted on my pre-inspection (my own - not a professionals) is now starting to make me curious as I am getting prepared to adjust valves and check to see if the tensioners have collars on them as the car has not been upgraded with hydralic tensioners.

I will get some pictures later this afternoon but it appears a PO used some sort of red permatex or some such sealer on the valve cover nuts. Are these a common leak point? What are the potential issues I might find as I dive in to remove the valve covers and adjust the valves?

Was this vintage subject to head stud failure?

Sealer should not be required on the valve covers, they go on dry. If your valve covers are perfectly flat with new gaskets, they won't leak. I like to use the (red) reusable gaskets, buy them once and use them over and over.

Once you get the valve covers off, put a wrench on each head stud to see if it's secure. No need to muscle it down. If, when you get the covers off and a broken head stud falls out, then that will answer your question right there.

SCs can certainly have broken head studs. It's been said that seldom driven cars taken out for short trips for can be susceptible to breakage. When you drive the car try to avoid short trips. I don't mean to say "never", just get some heat into the engine on a regular basis.

My SC had 180,000 miles and all the head studs were nice and tight when I sold it.

Lots of guys will tell you that you are supposed to replace the nylock nuts every time you pull the valve covers. It can be a nuisance if a nut starts to drip, and they can and do from time to time.

Hence the brand new nuts on both my Carrera and my SC.

PO probably smothered it in red RTV because they were weeping... a big NO NO NO! Clean sealing surfaces are a good start. If your cover seems not flat you can sand it down by throwing some 300-500 paper on top of some glass and sanding the surface flat. Then use all new nylocks and crush washers. I'll re-use mine for 3 valve adjusts (~1.5 years depending on noise) If one leaks I'll replace w/ new.

All SC's were prone to head stud failure because of the dilavar studs that were used. If all your original studs are intact I wouldn't worry about it too much, but I would inspect the studs where they are exposed to the elements. Especially the lower studs as those are the questionable ones. This is where they leave the case and enter the cyl. and where they enter the head. If you find corrosion (not burnt oil) then you should start planning your head stud replacement party.

There are several good replacements out there: OEM Steel, OEM 993, Supertech, etc... You will have to tear it down some, but its not too bad a job.

I have a recently purchased SC with a broken head stud, trust me this car is no low mileage garage queen. Any SC can break a head stud.

The don't leak from the nuts, they leak from the gasket and drip off the nuts. People put all sorts of stuff on the nuts and the gaskets to get them to stop leaking. Just do like "Euro" posted earlier and make sure the covers are flat, the sealing surfaces are clean and your torque is correct and they will not leak.

Most cars around now have also changed out the original valve covers for the turbo ones, most agree that they are stronger, more flat and have less of a tendency to leak. I'm one of those who when about to do a valve adjustment, will buy the complete kit from Pelican which do include new Nylok's ....so I change them out. Good luck