the thing about the cam covers is that they are made of magnesium and usually will have some corrosion after 20 years of service,
if the mating surface isnt perfectly flat all the way around then the gasket will eventually start leaking,
adding the sealant to the covers adds additional sealing capability to the gaskets and the uneven mating surfaces.

This same idea goes for the oil fill tube,
usually this part will deform a bit and then an oil leak will be created.
Using a nice smear of the HB4 on the mating surfaces will prevent future leaks from the mating surfaces

 

This ^

The audi cam covers are exactly the same in that the factory says put RTV in the sharp corners where the cam bearing caps meet the head. There is good reason for this as trying to get the rubber into such a sharp corner is almost impossible. The oil will use capillary action to find its way out.

This would be true if the inside surface (the surface closest to the valve train) is corroded. The outside surfaces don't do the sealing and the little rib is there to prevent the gasket from sliding out of place.

No problem using any kind of sealant anywhere. Just whether it is necessary or not.

The integrity of the seal must be called into question if it starts to leak after a couple of months.... I would like to see evidence that a dry install (except where noted by the factory) causes these leaks....

If your seal is sliding out of the cam cover it needs to be cleaned better. It will stay in place on any of the ones I have ever seen as long as there is no oil.

 

Sorry if this seems stupid, but are you replacing w/ the engine in? My '81 16V leaks like a sieve. (Wife calls it the Exxon Valporsche). I have replacement gskts for valve and cam covers, but wanted to know if it's practical without yanking the engine. I'm just starting to rebuild this car that I bought last year, but this is one of the bigger concerns.

 

Trenton you dont have cam covers,
you have cam towers, these are sorta bitch to replace but can be done with the engine in the car

NOTE the new gaskets go on dry

FWIW get your cam tower gaskets from Greg Brown at performance motor works,
even if you have already bought some

 

If it's the passenger side, it's not too bad. Plan on atleast 8-12 hours of work total. A couple of tips - remove the everything in the way first - fuel lines, coolant tanks, etc. Also remove the cam gear, it'll make your life easier as you remove the cam tower and reinstall. Make sure you get a slave lock or keep the engine in gear. check your cam timing marks and tension. Do a search there's a lot written up on it and get Greg Brown's gaskets...

 

I have both sides leaking. Passenger side at the rear, and drivers at the front. The p-side "might" be from th small cover at the back, but the front is coming from behind the cam gear and is quite profuse.

 

If it's coming from behind the cam gear then atleast you don't have to remove the cam tower...there is large metal seal behind the cam gear and is a common leak spot...

 

You have no idea how happy that would make me. Can that back cover gskt be replaced without removing as well? In the service manual it's called the "end cover" on pg. 15-2......It'll be tough to reach, but I think I can get it from the bottom side........

 

short answer is ... YES.

 

I used sealant in the cam cover groove, inserted the rubber gasket, then lightly mounted the cam cover temporarily to a spare head (not mounted to an engine) and allowed the sealant to firm up overnight. That then held the gasket in its correct position while I manipulated the cam cover onto the engine with it in the car. I also used a dab of sealant in the four 'corners' of each cam cover. And I also used the additional washer on each cam cover bolt. Repeated process for other cam cover. No leaks.