Found Collection

       I am looking for a low cost muffler for an older OS40FS engine. Does
anyone know for sure if the muffler for the Tower 46 B.B. engine will fit???
If it won't fit, will the muffler for a Tower 40 ABC work ???? The hole spacing
for the muffler on my "SF" is 1.450 in. & it uses 3MM screws.  Any information
will be appreciated. ----------Ray                    

Ray-
If I'm right in assuming you meant 'SF' where you wrote 'FS,' then
yes, the GMS/Tower 46 muffler will fit.  Dunno 'bout the Tower 40
muffler.

Ian
San Diego

Ray,
Do you actually mean a a40SF.   I have one and have been using a Tower
46 muffler for about nine months.  It will increase your RPMs about
1500 or so.  Works great.  Be sure to take out the long bolt that
holds the pieces together and replace them with a 6-32 or 8-32
threaded rod and double nut both ends.  I also installed  4mm bolts to
hold it on the engine.  You could also use 6-32 for that.  There is
plenty of aluminum on the crankcase to do that.  If you don't make
these changes, you will probably lose the muffler or parts of it.
Have fun.
Gene   K8JQZ
Palm Bay FL
Land of Year round flying. (Except during Hurricanes)
AMA 531730

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