In one of the videos, the Atlantic British tech says putting silicone on the front cover gasket is a “big no no” or something like that - I was surprised to see him spray gasket tacking directly on the front of the engine with some getting into coolant ports. Everyone has different methods.

For whatever reason, I like the idea of silicone on the front cover since I’m concerned about getting the seal just right (I’ll torque bolts to manual specifications).

Any input on this? Why did he make a big deal of criticizing silicone on the front cover? Which should I use? I have black extra oil resistant silicone (Permatex stuff). I’ve also got the copper gasket spray and maybe another type, but I started using silicone on everything. Speaking of which, should I use loctite or silicone on the bolts? Or nothing, just clean them and the holes and install?

 

Getting the spray in coolant ports and around mating surfaces won't really hurt anything, but I personally prefer to.spray the gasket itself when I use the stuff.

The biggest thing with silicon is to make sure you only use a VERY thin wipe. Like barely painted on. Any excess that squishes out can fall off down the road and clog up your oil pickup tube.

Cork gaskets you only install dry. I like cork for oil pans especially, and also for valve covers. Some folks hate cork, but I'm a big fan. Good surface prep is necessary.

Metal gaskets I like to use copper spray. Seems to help some.

Paper gaskets I will install dry *if* the mating surface is very clean and true. If there are any nicks or imperfections I will use a very very thin wipe of silicon on both sides of the gasket.

Rubber gaskets always get a very thin wipe of silicon, but I generally don't like rubber gaskets much. O-rings do not count in this category. O-rings get a wipe of grease or oil. Never anything else.

Head gaskets I always install dry.

As for the bolts, most bolts get installed dry. Which bolts in particular are you referring to? I like a bit of loctite on the cam bolt, any bolts going into water passages get thread sealant or grey silicon.

 

Thanks Alex,

The bolts I’m wondering about mostly are the front cover bolts and the sump bolts. I used black silicone on the water pump bolts that I put on the new front cover. I’m not really sure what’s different about the grey silicone, but I just have black and black high oil resistance right now (and loctite blue). I can try some loctite on the cam bolt. Do any other pulley bolts get sealed or just tightened? I think the sump gasket is silicone? I’m not sure if I should use another layer or silicone on it, or just install it. I’ve been using silicone on most things, which for some reason gives me a sense of security that if a surface or thread is a bit off, it’ll still hold it together and prevent leaks. I think the front cover gasket is paper and I’d probably want to use silicone to make sure it seals well, but I’m not sure if doing that is actually asking for trouble here by creating more of a gap - I guess the idea is to always use just a very thin layer of it. If it’s best to install that one without anything or just spray the gasket spray on it (not sure if that stuff is to temporarily hold it in place or to help seal or both) maybe I’ll just do that instead - always into hearing what others do.

 

Here are a couple details. 1. There is a long water pump bolt, maybe two that penetrates into the water gallery. It (they) need high temp thread sealant. The white loctite worked for me. 2. The front cover gasket is paper based, but there is a coating that really sticks as it is put into service, and raised portions for the water passages. In fact, if you put a silicon skim coat, it will be a bit easier to remove next time.

My mechanic says the grey silicon is a bit stiffer than the black. I think it is especially made for aluminum with high bolt count patterns. The curing/torqueing protocol is a little different than the black, with higher resistance to vibrations.

The sump may need a dab of silicon wherever two pieces (like the front cover and block) are mated together to seal those leak paths. Hope this helps. Remember, this is fun!

 

I’m not sure exactly what to use but thinking I’ll get black “right stuff” for the timing cover and sump. I think grey is for high torque. I could get some red right stuff for the water pump bolts that apparently touch the coolant - not sure how far in they go exactly - I’ll put the sealant toward the back threads. Not sure if red is necessary or black will be fine too.

This one has a picture of a timing cover and sump on it so that kind of sells me haha along with good recommendations from a few people here. I used black silicone on the water pump gasket and the shorter bolts - hope that’s alright - asked someone and they said to do it.

I think the timing cover gasket is paper right? Hopefully the one I got with the cover from rockauto is a decent gasket and the right stuff will help it seal well.

https://www.oreillyauto.com/detail/c...ht+stuff&pos=2