Screenshot below just to confirm I'm not making it up! In general, I agree with Dan, no additional sealants applied to gaskets except in very specific cases. And never, ever,
ever apply sealant to M119 valve cover gaskets (
link).
For the ETA gasket, the Hylomar is a non-hardening sealant that essentially aids installation and sealing, plus keeps the gasket from sticking to the ETA over years of use so next time, it pops right off without scraping.
Side note - although the FSM spec is 25Nm for the ETA bolts, I have *never* used that much force on them. Typical torque for an M6 fastener is 10-12Nm, and an M8 fastener would be ~25Nm. I don't know if it's a typo or not but I have no interest in either breaking bolts or stripping threads, so I stay down in the 12Nm ballpark. Note you are also supposed to replaced the microencapsulated bolts, but I typically clean and re-use them with sealant applied.
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