Bent exhaust flange. What to do?

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The flange I bolt my muffler to is bent back along part of one side about midway between the two bolt holes. When bolted up, exhaust will shoot out that side. What can I do. I don't want to replace the flange because it would require pulling the generator from the motorhome--a huge job and beyond me. I wonder if the liquid metal or some other stuff like that might be able to fill the gap.
 
ive never been able to get exhaust sealer type products to work as advertised.

best thing you can do is pull the flange and fix it proper. this way you know its not going to blow a seal and become loud while youre out on the road somewhere and annoy youre rv neighbours.
 
Years ago I left San Diego for Vegas. After I arrived and the engine cooled, it suddenly had an exhaust leak. Investigation revealed the flange connected to the exhaust manifold had warped exposing a gap. I filled the gap with a product called thermo steel. It held all the way home. Eventually it failed and Ford replaced the y pipe (out of warrantee)because it was a common problem. Later the manifold cracked and now I have gale banks headers. No more problems. However, I would use this product again if it was a little further downstream where it doesn't get so hot. If your flange is at the head or manifold you should remove and repair properly as suggested above. That is the only way it's sure to hold up.
 
The flange is at the bottom of the generator tray and is fed by manifold pipes that are at least 8 to 10 inches long to the closest exhaust port. I just hope that the piping up in the cooling shroud is not leaking as that is what I can't get at. The previous owner of this motorhome had bashed something with the muffler. I am moving the muffler to a safer location between the frame and driveshaft.

I'll look for the thermo steel.

Thanks
 
Room for a gasket?
Or a double gasket. A metal gasket, thicker copper or brass sheet metal might work; soft enough to sqweeze to shape yet take the heat.
May last until a better fix comes along.
 
Can you layer on something like JB weld, than a layer of Saran wrap (to prevent sticking) and than bolt up the mating flange to "squeeze" the JBW flat?
 
Quote:


Can you layer on something like JB weld, than a layer of Saran wrap (to prevent sticking) and than bolt up the mating flange to "squeeze" the JBW flat?


That's what I was thinking, but was going to use maybe masking tape on the good flange bolt it up and pack the JB in. Hopefully once cured and the gasket installed it will hold.
 
Quote:


The previous owner of this motorhome had bashed something with the muffler. I am moving the muffler to a safer location between the frame and driveshaft.




Good plan. Man do the OEM's put those generator exhaust outlets in terrible locations. REAL easy to snag them on something. You see those skinny little exhaust pipes sticking way out the sides, etc.

Joel
 
There is an optional side exhaust outlet from the piping. If they has made the side basement compartment about 8 to 10 inche narrower (which would have been fine as I hardly use that compartment) the muffler could have been tucked up and out of harms way. As it is I have to use the bottom outlet, but will do a 90 turn right away and take the muffler up between frame rail and driveshaft. That means a 44" pipe from muffler outlet to side, but oh well, better than bashing it off. Unfortunately the main engine muffler also hangs low, but I suppose I could have it rotated at a muffler shop. Then I would be in great shape. Generator installation instructions do say to install a skid shield for any parts that are exposed below, but manufacturer didn't bother.
 
There is an alternate flange on the side, so I pulled the plate off of it and put it on the bottom flange which is the bent one. I used JBWeld to fill the gaps. This was last Sunday. Haven't started it yet because still working on getting the muffler and pipes together and installed.
 
Hate to break your bubble,,,but as a 2part epoxy (plastic), JB weld is gonna melt/fall out soon as heat builds. I use a product at my shop (custom exhaust,muffler shop a specialty) called "Muffler Cement" that will fill and STAY in gaps up to 3/8". Have no idea if it's available anywhere but exhaust specialty suppliers. If you like I'll try to get company name,address, contact number first of the week. Second choice would be old fashion stove and furnace cement, as used to repair/fill gaps in woodburning stoves,furnaces, and fireplaces. This product is available locally in this area at a mom and pop hardware store. Have never noticed it in the HD-Lowes stores,,,,but then again, I've never looked for it there. This is kinda like a gritty-sandy filler that is extremely brittle after hardening, but it will also fill gaps reasonably well untill it's taken apart again.

Bob
 
Interesting, the JBWeld pack says it withstands 600 F. Anyway, the muffler shop told me to get muffler cement. Will have see if anyone around here has it. Maybe I'll google it.
 
Actually there is some piping from the port through the fan shroud and out the side and bottom. I'm going to guess the location of the JBWeld is now about 12 inches from the exhaust port. Also, since I am taking it out the other opening, there is about 6 inches or so of dead end pipe to this repaired port. Might work. I'll soon see. Got the muffler and piping about 75% installed yesterday, just have to put a tailpipe. If burns out, will look for the muffler cement.

Thanks
 
Red high temp silicone may seal it.
It worked on my Taurus muffler that had a small rust hole.
 
"Red high temp silicone may seal it.
It worked on my Taurus muffler that had a small rust hole."

Why do you suppose I don't keep a tube or two of this around ,instead of a whole wall of my shop covered in approx $1,200.00 in gaskets?

Bob
 
When did fel-pro start making muffler rust hole gaskets?
It was a temporary fix until i could get to it when i had time.

"Why do you suppose I don't keep a tube or two of this around ,instead of a whole wall of my shop covered in approx $1,200.00 in gaskets?"
 
I believe Paul was looking for something more permanent. Do exhaust every day for the past 20+ years. Products I mentioned will work till joint is taken apart again.

Bob
 
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