Best RTV for engine rebuild?

[94CobraPace]

What RTV is best for sealing up a engine on a rebuild? Blue, black, copper or ????
I usually use blue for water pumps.
I'm putting together a 351W & am wondering what is best to use on oil pan, timing chain cover, water pump & intake ends & what ever else needs sealing.
I'm open to using different ones for different parts.
What is best for head bolts also.
What have you had good luck with?
Thanks

 

[1320stang]

I hate to say it, but the stuff I use comes from the Mopar parts counter. My buddy is an ex Mopar mechanic and he gave me a few tubes of it and it's great stuff. It's black and I think they have 2-3 different kinds depending on it's use, and it's expensive, like $10/tube, but I've never had a failure with it. I figure the best for my stuff if it comes down to tearing it apart to fix a leak later, cheap insurance in my opinion.

I've got an old college buddy that works as the parts manager at a Ford dealership nearby and the owner also has a Mopar dealership next door. When mechanics get a job and they go get their parts from the parts room, they usually get a tube of stuff to use and they never use it all so they stock pile it in their tool boxes. The parts manager told me the Ford guys go over and trade, I think it's fuel injector flush, for the Mopar RTV as it's better than the Ford stuff they have.

 

[sand1man]

On my oil pan and valve covers I use 3M weatherstrip adhesive, it makes it a B%$#@ if you ever have to take it off but I have never had a leak

 

[PoliceInterceptor]

Absolutely as little as possible. I HATE RTV, it is way over used.

However, "The Right Stuff" is really good when you do need it.

 

[D.Hearne]

The "yellow snot" is absolutely the worst stuff known to man for engine use. My favorite is Permatex "Ultra Blue". For head gaskets, Copper Kote.

 

[zookeeper]

Like everyone else, I have my favorites. I prefer Permatex Black, and use it SPARINGLY! I wouldn't use blue for anything.

 

[10secgoal]

Conflicting opinions. Haha. I like RTV black, and permetex blue. The blue is much easier to remove when it comes to take it off again.

 

[GypsyR]

Since I've owned two vehicles that had engines "killed" due to excess RTV clogging up the oil pump pickups, I avoid using RTV as much as possible. The one exception is sealing the front and rear of a V8's intake. ALL other gaskets I seal with Permatex "Aircraft" brush on sealer. The only sealer I've found that works really well on a 30 year Harley that will vibrate your teeth loose. The stuff works great on cars too. And if you make a mistake during assembly and have to take something apart, odds are very good that you can not only get things back apart easily but you might even save the gasket for reuse. (NOT head gaskets!) This is nice especially for valve cover gaskets, which often have to come off a time or too for checking/adjusting valves.

 

[rbohm]

i usually use either black rtv or permatex #2. either way i use VERY THIN coats of either sealant, as i too have seen too many engines fried as a result of too much rtv, or other sealant that got into the oil or coolant and clogged up the works.

 

[65fastback2+2]

i love the copper rtv

 

[thehueypilot]

Absolutely as little as possible. I HATE RTV, it is way over used.

However, "The Right Stuff" is really good when you do need it.

I agree......the big three auto makers developed this stuff and use it exclusively. I have never had a leak since I switched to it. It costs more but pays for itself by preventing "comebacks" because of leaks. I use it in place of the cork manifold valley gaskets.