I'm trying to find a part number for an exhaust muffler for a Scotts S1642 with a Kohler CV16-43526 engine. All I've been able to locate so far on the internet is for Exhaust brackets and bolts, not the muffler itself.

Go to a small engine repair shop they can possibly match it up.

Hi,
Since it will have the correct brackets, etc. it is probably wise to settle for the Deere muffler. It is part #GY00296. You could possibly search around for one elsewhere, if you wish to look I think I would trust the different wholesalers who sell engines. I think the owners manual is still at:
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Peace,
Clarke