What is this red sealant?

[Evan Kornacki]

Does anybody know what this red sealant is, and where I can buy more of it? It comes pre-applied from the factory on Weber gas control valves (at least on the Spirit front-control grills.) It almost looks like some kind of RTV silicone, but I'm not sure if RTV will resist propane (I know silicone won't resist gasoline ... so I'm suspicious. I want to know for sure before I replace it.)

 

[Bruce]

I don't think it is a "Sealant" such as Red Hi-Temp RTV. I beleive it is a rubber/silicone gasket. I am skeptical that you would find a source for them without sourcing a whole new valve.

 

[Evan Kornacki]

I don't think it is a "Sealant" such as Red Hi-Temp RTV. I beleive it is a rubber/silicone gasket. I am skeptical that you would find a source for them without sourcing a whole new valve.

No, its definitely some kind of chemical that is hand-dispensed (like from a caulk gun) onto the valve. Its not a pre-made gasket. See the close-up below. Any ideas what they use?

 

[Evan Kornacki]

What do you guys use to seal the valve/manifold clamp-on connection when you're cleaning/rebuilding Spirit grills?

 

[Bruce]

LIkely something very similar to Red RTV.

 

[LMichaels]

It's simple red RTV high temp. LP/NG are not gasoline or a liquid state so they have no solvent properties at all. Just go to any automotive supply place and get a tube of red RTV. Now whatever you do, if you decide to use any of it on your car.........................STOP! Beware red RTV is NOT sensor safe meaning if you use it anywhere the "off gasses" can make it into the intake stream it will foul your O2 sensors and likely the MAF sensor as well. But on a grill there are none of those things

 

[Bruce]

https://www.amazon.com/Permatex-81630-Ultra-Temperature-Gasket/dp/B08CRY2BJB?tag=tvwb-20

Larry, I notice this stuff says "Sensor Safe". But I would probably not trust it real highly for that.

 

[Evan Kornacki]

It's simple red RTV high temp. LP/NG are not gasoline or a liquid state so they have no solvent properties at all. Just go to any automotive supply place and get a tube of red RTV. Now whatever you do, if you decide to use any of it on your car.........................STOP! Beware red RTV is NOT sensor safe meaning if you use it anywhere the "off gasses" can make it into the intake stream it will foul your O2 sensors and likely the MAF sensor as well. But on a grill there are none of those things

Are you sure?

I've been doing some Google-ing and it appears that silicone—maybe including Room-Temperature-Vulcanizing (RTV) silicone—is not compatible with propane. I don't want to put the wrong thing on there.



If you look at the above chart from Marco Rubber, it looks like Teflon, Viton, Urethane, and even Buna are compatible (as well as something I've never heard of called "Aflas")

 

[LMichaels]

It's silicon

Are you sure?

I've been doing some Google-ing and it appears that silicone—maybe including Room-Temperature-Vulcanizing (RTV) silicone—is not compatible with propane. I don't want to put the wrong thing on there.

View attachment 112215

If you look at the above chart from Marco Rubber, it looks like Teflon, Viton, Urethane, and even Buna are compatible (as well as something I've never heard of called "Aflas")

Believe me it'd red RTV like Bruce posted above. Sometimes Google is not your friend. It's misleading you. But hey, you do whatever you want or believe what you want.

 

[Bob Bailey]

It's simple red RTV high temp. LP/NG are not gasoline or a liquid state so they have no solvent properties at all. Just go to any automotive supply place and get a tube of red RTV. Now whatever you do, if you decide to use any of it on your car.........................STOP! Beware red RTV is NOT sensor safe meaning if you use it anywhere the "off gasses" can make it into the intake stream it will foul your O2 sensors and likely the MAF sensor as well. But on a grill there are none of those things

Need to disagree with you here Larry. Correct me if I'm wrong but unless MAF technology has changed dramatically since I've been out of the repair business, I see no way it could damage or cause any adverse effects to A MAF sensor unless it actually came into contact with the functional elements of it. which would be highly unlikely.

Isn't Permatex Ultra-Red sensor safe. Or am I confusing it with Ultra-Copper?

 

[LMichaels]

Need to disagree with you here Larry. Correct me if I'm wrong but unless MAF technology has changed dramatically since I've been out of the repair business, I see no way it could damage or cause any adverse effects to A MAF sensor unless it actually came into contact with the functional elements of it. which would be highly unlikely.

Isn't Permatex Ultra-Red sensor safe. Or am I confusing it with Ultra-Copper?

I'm going back to my wrenching days. Red sensor safe did not exist. I honestly (until Bruce posted that link) did not even know red sensor safe existed. I stopped wrenching like over 20 years ago. So that is the reference point I was coming from

 

[Bob Bailey]

After more thinking, I'm pretty sure GM used it as valve cover gaskets for their Target Master crate engines at least into the early 80s. What a disaster those were!
I closed the shop and quit wrenching in early 2002.

 

[Cody Bratton]

If a company like permatex says it’s sensor safe, I’d trust it. They make some damn fine products.

 

[LMichaels]

If a company like permatex says it’s sensor safe, I’d trust it. They make some damn fine products.

I would as well. I've always trusted their stuff. But, like I noted back when I was still doing it, none of the red was safe. So, I simply threw it out there from memory. I haven't bought the stuff in more years than i care to count