Generator exhaust disconnected at flange - gasket?

[CombatYoga]

Onan 5500
The exhaust exits the genny straight down under it and it ends in a flange.
The flange bolts together with the exhaust pipe and it continues on down and out the side of the RV.

The bolts that hold that connecting flange together must have vibrated out - the exhaust pipe is now dangling and only held on by the strap of metal where it comes out from under the RV.

Is there a high temp gasket needed where that flange bolts together to connect the two pipes? Or do I just bolt them up?

I took a picture of where the flange has come unbolted.

[A32Deuce]

Looks like you could just bolt together. They do make a silicone exhaust sealant you could use with it.

[Bama Rambler]

Since it's under the rig there should be a gasket. That's a pretty common exhaust flange on the pipe, so a local autoparts store should have a gasket that fits it. I'd take a piece of cardboard and make a template and take it to a parts store and let them match it.

[CombatYoga]

Yeah, it feels to me there should be a gasket as any small leak will gather fumes under the rig there, but I don't see any evidence that there was one there before (if it presumably fell off when the flange separated).

[A32Deuce]

You would not believe how many engines do not use exhaust gaskets. That genny exhaust does not get that hot that you can't use the exhaust silicone. Works great.

[ICanFixIt]

That upper pipe looks like it has a flare to hold a donut gasket. I'd bet it should have a small hard donut type exhaust gasket. Those flange brackets aren't connected to the pipe but hit a flare stop on the ends of each pipe and clamp the pipe ends together. A gasket between the pipe ends is used to seal them. A flat gasket between the flanges probably will not seal as the pipe ends have to be sealed, not the flange brackets. Have you checked on top of the bottom pipe to see if a gasket isn't setting on there that you can't see from underneath? You should be able to pick up a donut gasket at any small engine repair shop or of course Amazon. This is just from looking at that pic so I could be wrong You really need to get up there and get close to see how they seal.

[CHICKDOE]

send an email to onan. i just looked at their accessories (exhaust and tailpipe section) and there is no mention of a gasket. it wouldn't hurt to check with them

[overeasy]

If you look at the generator flange you can see the outline of the old gasket which looks to be a common lawn mower exhaust gasket