Need Help: gasket sealant
 

here is my question will gasket sealant harden and seal up in cold weather. im asking because right now in chicago weather is pretty cold and i need to put my intake manifold back on and im concerned that the gasket sealant wont seal up all the way because of the cold and i will have another major oil leak.

Let the RTV sit for about 15-20 minutes before you put the intake on, otherwise you're just going to squeeze it all out. I'd think it would harden better in cold weather than hot. It depends more on the humidity than the temp.

Just be sure and let the car set for at least 24 hours after completing the installation. This will allow the sealant to harden and minimize the risk of the leak coming back.

i did a test. i put rtv on a piece of metal and put it on another piece of metal and let it sit for 24 hours. i went to the garage and pulled the two metal pieces apart and when i did the rtv under the two metals was still not dry. im scared to put this on my intake manifold and have it not dry and get a major oil leak.

What kind of RTV did you use? I would let it sit 48 hours myself, but it depends on the weather conditions, humidity and how thick the bead is. Once the intake is torqued down, there isn't much thickness to the RTV and it'll dry faster than just putting it on a piece of metal and letting it sit.

You don't want to let it sit without putting the surfaces together. It's best to do it right away. I've spoken to the guys at Permatex and that's what they said. The chemical starts to harden when it's compressed, that's how it's designed.

You should let it cure for at least 24 hours before turning the car back on. I'm not sure how many RTV brands are out there, but all I know is Permatex. For heavy duty stuff, I would use their "The Right Stuff."

I'd go with "The Right Stuff" It's supposed to instantly seal and it's STRONG. When I pulled my motor for shits and giggles I removed the intake bolts to see how strong The right stuff was and I had it hanging by the intake. (I left it attached to the engine stand and only lifted it a few inches so that it could not fall)
Mike

I'm not sure how much weight you actually lifted with it still attached to the engine stand, but that is interesting. Is The Right Stuff as oil resistant as Black RTV? I liked the Copper RTV and it sealed great last time.

All their stuff is oil resistant, but gasoline will make it swell up like a balloon. "The Right Stuff" is their top one, instant seal and all. Ultra Copper is mostly for headers/exhaust cause it withstands the most heat.

the one iwas going to use is permatex high temp rtv silicone gasket maker

I always use the Permatex Ultra Blue, seems to work well, but you have to be sure you give it a day or two to cure.

I'd use The RIght Stuff for the intake as well. It's good stuff!

Info
 

I use permatex the right stuff all the time I have used it on transmission pans differential covers valve covers and slot of other stuff it's similar as Pernatex black and red RTV it's black is in a can that is pressurized with air and you pull the trigger tords can to bend tip to release gasket maker only difference is between rtv and Permatex the right stuff other then triggered can is it cures in 1 minute its for industrial strength can be used for anything that needs a fast gasket I use it slot on my track cars also a lot on my daily drivers when I change diff fluid and don't want to be down a day or 2 because of gasket from rtv I just use the right stuff because once it's on I wait like 10 15 minutes and bam I'm back on the road

FWIW, I measured .035" (.88mm) gap between the block and intake with the intake just sitting on new gaskets.

Put it on, maybe let it tack up after 10min then put intake on and let it sit for a day. The block will heat up and get toasty in there to help cure it.

Whatever is decided, don't start the car until the sealant can have a good 24+ hour cure time. In colder weather I'd give it 48 hours, especially when it comes to the intake/block sealant.

whatever product you are using...there typically are "directions" which include use within "x" temp range...so read the label

Screw instructions! Nothing fun comes from reading them!

Hillbilly hint: get some non LED Christmas lights and lay it all around the area you are trying to dry, the lights get warm enough it’ll help raise the drybulb temp in that area. My boss shoves Christmas lights in the engine area of his I/O boat when it drops below freezing before he winterizes it to prevent freezing, same principle here. Keep the intake manifold and the RTV in your house to keep them warm, then go stab it on, lay a couple things of Christmas lights around the intake, close the hood to keep the heat in, and you’ll be both festive and it should dry. I’d do 48 hours too if you can, and a car cover will also help hold in the heat.