I need to know what to use to seal the camshaft housing, espeially right above the exhaust manifold. I have some Permatex Ultra Black the is good up to 500 degrees and has good oil resistance. I figure it's not as hot as the catalytic converter but would this sealant work between the cylinder head and camshaft housing? I think it would be fine on the timing chain cover and valve cover.
This is probably very close in specification to the Permatex product but it is specific to engine sealant. It has been used in GM engine assemblies for years. You may want to read the specifications in the link provided.
Googling the spec'd sealant you can find on Amazon, or maybe alternatives. Similar application on Hondas I used Permatex Ultra Grey.
I did call permatex today and they said their Ultra Black would work well as it has high oil resistance and can take up to 500 degrees and high vibration. 500 degrees is slightly higher than the OEM spec. However, they said the stuff I had in my hand was nearly 3 years old. The first number stamped on the tube crimp is the last digit of the year made and the next letter is the month of manufacture with the alphabetical letter position corresponding to the month. For example, a tube marking starting 8E would have been made in 2018, May. They said anything over 2 years old is not going to perform correctly. New, fresh sealant could go over 2ooK miles but stale stuff could fail at any time.
I don't think that would be the end of the world though. Looking at the image I posted above, it's at a three-way junction, of the valve cover (above) the timing chain cover (to the left) and the cylinder head (to the right). I guess they figure there's a little give in that joint, could be leak prone. There's a similar instruction if you're putting on a Honda valve cover: just a little dab at that junction. In most cases the cams were belt driven, so keeping it completely sealed was more critical:
I used Permatex Ultra Grey “The Right Stuff”. In the can with the nozzle built onto it. 4mm bead and installed it within the specified working time. No signs of leaking as of yet. And the OE stuff I scraped off was grey too.
