Flo-Pro 1953 muffler for the onan

I have patched up my original onan muffler a few times with the mig welder.  It is getting pretty thin, and with my new A/C unit, I want to be able to run the onan more often without worry.   I searched and decided to buy and install an alternative Muffler.

Flo-pro 1953 muffler bought online from Bumper Super Store.com

$61.32

removed down tube and old muffler.   I also replaced the exhaust manifold gasket.

Comparison of the two mufflers

On the original setup,  the downpipe went over the entrance pipe to the muffler.

my downpipe was not terrible.  I cut a little rust off the end, and used a wire wheel to clean it up.  the rest of the pipe feels pretty solid.

on the new muffler, the opposite fit works great.   The downpipe fits nice inside the inlet pipe of the muffler.

Test fit,  it looks like it will be just right.

Final Fit before Welding the bracket.   I cut the bracket off the old muffler.  Heated red hot with torch, and pounded it with hammer to countour to the new muffler.  a quick hit with the Welder and it will be just right.   I also cut 4 slots into the inlet of the muffler, so it will clamp down tight.

Very close to the onan box,  but it fit very well.  I think I am going to add some more exhaust pipe.

This is DB reading from inside hallway with old muffler

DB reading inside hallway with new muffler.  It is a bit louder.

DB reading of original muffler outside

DB reading new muffler outside

As you can see by my DB readings from my iphone app, it is a little bit Louder.   However, looking at how the muffler is installed, I think by adding some more exhaust piping to it to direct the noise down and away a little bit, I think I will see another drop.  this muffler is 1.5" outlet, and I can find muffler pipe in that size. 

  Update.....   I installed about 8" of tail pipe,  with part of a 90 degree elbow.  it made all the difference.  You hear both the engine noise, as well as exhaust noise now.   This little piece of pipe quieted it down quite a bit.

Ended up 1 db quieter outside

Same as old muffler now inside.