Can you a trimmer muffler on a riding mower

daileyjames0 , Not a good idea. Do you have a trimmer engine on your lawn tractor, probably not. Your yard trimmer may be 35cc, and about the smallest lawn tractor or at least now a days would be 306cc , the trimmer is only a tenth of displacement. The larger displacement engine requires a larger muffler for less back pressure/less restriction to get rid heat/exhaust . In adapting such a small muffler such from of a weed eater probably would restrict exhaust creating too much back pressure in tern loss of power, possibly cause internal damage burnt valves,etc., overheating, etc. If you can get the correct muffler for your application, it is advisable to do so to keep your engine running better. Good luck.

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