Oil leaks Westerbeke W50

[felizcortez]

I have a few leaks on my Westerbeke W50. I believe the rocker cover is leaking. It looks like someone used a gasket sealant instead of a cork gasket. I have a replacement cork gasket and want to swap it out. A few questions.

Should I apply the cork gasket dry? I've heard of some people using hylomar or grease on the mating surfaces.

I believe I have a second leak where the oil likes go into the oil cooler. It's the second picture. There are some right angle brass looking pieces that thread into the cooler. These appear to be leaking. I tried to tighten these a bit, but they didn't budge. Is there some sort of thread sealant I should be using e.g. like when you use plumbers tape on a threaded junction. Not sure if that works or if it even exists for oil because the temperatures are higher.

Any advice is appreciated.

[Lepke]

Use a gasket sealant on the cork. In racing, sealant is placed between the valve cover and the cork, but grease between the cork and the head. That seals good enough for the short time between valve settings, but probably not good for long term in a marine engine. But do adjust the valves while the cover is off.
Use teflon tape on the threads. It could be the threads are shot from being turned too far. You could need new fittings.

[Compass790]

What Lepke said but you can use Loctite hydraulic pipe sealant or similar on the threaded fittings too but thread tape is cheaper. It laughs at your oil temp.
Silicone or hylomar or Loctite 518 will work good on your cork gasket. I find you have far less problems if you DONT put gaskets on dry.