I really like the Curtis Youngblood Muscle Pipe on my O.S. 90 engine. It’s small and compact, lightweight, looks good and does a great job of letting the engine breathe for maximum power while keeping the noise down to a pleasant level. Unfortunately, I had another one of my mishaps which caused the mounting flange of the muffler to crack right where it attaches to the header. I had a machinist look at it in the hopes that it can be repaired, but because of the position of the crack and the fuel residue it did not seem possible.
I hate to throw anything away, so when I got the Muscle Pipe home I tried to think of some way to fix it. One of my favorite fixem-up materials is JB Weld. If that can’t fix it, then nothing can. So, my first job was to get rid of the fuel residue, which I did by spraying down the pipe with brake cleaner. Once dry I used a wire brush to clean up the pipe and the header. I then applied a small amount of JB Weld to both the header and pipe flange where they meet, and then bolted the two pieces together. A little extra JB Weld was then added around the mating area to secure the mounting bolts in place. After waiting overnight for the JB Weld to cure I was very pleased with the results. As you can see in the photo the JB Weld did a nice job of securing everything together. Now all I have to do is clean and polish the Muscle Pipe and header and reinstall it on my helicopter. I’m sure the Muscle Pipe will work as good as new, but if I have any problems I’ll let you know. Also, if you have any better ideas on how I could have fixed this Muscle Pipe, please let me know. I’m always interested in new ideas and techniques.
I dont think your JB weld will hold up to vibration+heaat but hope it does.
You can buy a rod of aluminium alloy to virtually solder such a crack. It melts at a temp well within a normal propane soldering torch.
Clean the joint as you did. scrub joint with a stainless steel brush(only stainless) you can buy 3 brushes for $2 at the dollar shop.
Then heat the muffler crack or hole and touch on the rod the joint is hot enough when the rod melts and you can run a nice bead of the silvery alloy down the joint or over a hole etc for a bond that is stronger than the base material.
The product is usually called Aluweld or similar and a 10″ rod costs about a $1. PS it welds all alumin and alumin alloy parts just with a cheap propane torch.(9even those propane lighters if you can get the base metal hot enough ie small parts).
It wont stick to tin so by wrapping a job areawith a piece of tin can, you can block a hole or rebuild say an engine lug.