If you want the very best, then it is the Mercury Marine Quicksilver Perfect Seal part number 92-34227Q02. It is a non-hardening sealant similar to the Permatex aviation stuff. I have found it to be better.
You can get it at your local Mercury Marine or Mercruiser agent. They don't tend to advertise it or have it in their online shops because there is a limited customer base who use it. I can't remember exactly where i got mine, but it was a guy in a boastshed on the Parramatta River near Putney where i lived at the time.
It is more expensive than the Permatex, especially if you are only doing a single engine, because it only comes in a (US) pint can and is around AUD$65 typically, and will only last about 6 months once the can is open.
However, 10 years down the track, there are
NO leaks from any of the gasket surfaces that this was applied to. This includes difficult ones like the timing cover that always seem to be too beat up to seal properly. $65 to have a leak free engine is cheap in my book.
This was recommended to me by my engine machinist and he is one of the best in the country.
Some links to sellers after a quick search:
https://www.completemarinesupplier.com.au/shop/product.cfm?categoryid=962&productid=7548https://www.amazon.com/Mercury-Quicksilver-Perfect-Compound-93-34227Q02/dp/B007I8YFZShttps://www.ebay.com.au/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=quicksilver+92-34227q02&_sacat=0&LH_TitleDesc=0&_odkw=92-34227q02https://www.marineengineparts.com/mercury-marine-92-34227q02-pint-can-sealer
_________________
the world is a book, and those who do not travel read only a page
66 Mini Minor sponsored by
http://www.lifeonthehedge.com.au/ The Dog Harness Specialists
It was a pleasure ausmini. I'll miss all you misfits and reprobates
