Husqvarna 4623 - Muffler

nevils

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I think the correct replacement part # for the Husqvarna RZ4623 muffler is 532149723

It sat unused by the prior user for at least a year, maybe more, and now that we're running it the muffler seems to be getting louder, fast.

Will I also need the gasket set?

Does the picture suggest that I also need to replace the pipes - or should they be OK?

Has anyone swapped-in a different muffler that's quieter, or modified the OEM muffler somehow?

Thanks!
 

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ILENGINE

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Pipes should be fine, but may want to look at them a little closer. The muffler has some surface rust but otherwise looks OK also. Could possible be a leaking exhaust gasket which could cause more noise. If you look around were the pipe connects to the engine you may see evidence of carbon blowing around the gasket. Otherwise no need need to remove the pipes if you are just replacing the muffler. the pipes just slide into the muffler without a gasket or seal.
 

nevils

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It appears that the mounting bolt for one side has worked loose and fallen out!
 

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ILENGINE

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Exhaust gasket and bolt should fix it/
 

nevils

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Exhaust gasket and bolt should fix it/
Just looked again. I found a bolt that fits ... but then noticed that the gasket is missing. I'll order a set. Thanks.
Hopefully these 2.5" gaskets are correct - just ordered them ...
EDIT: Definitely not the correct ones. Need 1 1/2" size, I think.
 
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bertsmobile1

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Apply nickel high temperature anti sieze to the bolt before fitting as they are notorious for corroding solid into the head
And note they are socket headed allen bolts not std hex heads because you can not get a socket or wrench onto a hex head
 

StarTech

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Just looked again. I found a bolt that fits ... but then noticed that the gasket is missing. I'll order a set. Thanks.
Hopefully these 2.5" gaskets are correct - just ordered them ...
Most likely the wrong ones...Exhaust gaskets needs to be for the make and model engine installed on the ZTR. Post the make, model, and spec numbers.
 

nevils

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Apply nickel high temperature anti sieze to the bolt before fitting as they are notorious for corroding solid into the head
And note they are socket headed allen bolts not std hex heads because you can not get a socket or wrench onto a hex head
Yup, I did ... after a minute ... figure that out. lol OK re. anti-sieze. Thanks!
 

nevils

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Most likely the wrong ones...Exhaust gaskets needs to be for the make and model engine installed on the ZTR. Post the make, model, and spec numbers.
More detail than this? "Husqvarna RZ4623 muffler is 532149723" Does this help at all? Thanks!1713141708865.png
 

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