Most of the opposed cylinder Johnson Model A motors have the inner mufflers missing or badly deteriorated. You can easily make a replacement that is spot-on for the original with common 2" copper plumbing tubing available at many home repair or plumbing stores.

Here is what you need:

- Tape measure
- Pipe cutter
- Starpie marker
- Set punch
- Hammer
- 1/4" drill bit
- Dill press
- Misc wood blocking
- 2-inch copper tubing

Here's how to do it!

Illus #1 . 1929 Johnson A-45	Illus #2. A-35/A-45 Parts book - inner muffler on upper left
Illus #3 . Measure distance between muffler ends (this will vary due to distortion of the muffler ends)	Illus #4 . Ring compresser used to draw line on copper tubing
Illus #5 . Pipe cutter makes a nice clean cut	Illus #6 . Parts manual indicated 12 holes evenly spaced (this worked out to every 1/2" on this example)
Illus #7 . Use of a punch to dimple the copper makes it easier to drill. Note wood blocks used as cribbing to hold tubing	Illus #8 . Holes drilled with a 1/4" bit
Illus #9 . Test fit new inner muffler to be sure of a good snug fit.	Illus #10 . Leftover copper pipe can be used to roll out any dents in the outer muffler can
Illus #11 . Install inner muffler with holes facing down	Illus #12 . Motor is now ready to run and will be nice & quiet

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