New PT425 Muffler

[marrt]

While I’m in the posting mood today, since I can’t drive my tractor /w3tcompact/icons/sad.gif, I thought I’d fill you in on what I believe is a new muffler design for the PT425. In the past, I think 425’s had rear discharge mufflers. Take a look at the attached picture. As you can see, this is a side discharge muffler and I think PT likely builds it themselves. Also, take note that the exhaust exits on the left and right sides are different sizes. That’s because no exhaust actually exits the left side! This is apparently an air intake for the muffler. Exhaust coming out the right side actually pulls air into the muffler from the left side. This causes the muffler to run cooler and mixes fresh air with the exhaust to lower the sound volume (similar to the way modern jet engines do the same) and to dilute the exhaust smell.

At least that’s my theory. It could be that exhaust is supposed to exit both sides and my muffler is broke. /w3tcompact/icons/wink.gif

 

[marrt]

Another Pic from the side...

 

[MossRoad]

That is very different from mine. I've attached a picture of mine for those that want to compare.

 

[duane]

Marrt,

Is the rust on the muffler due to the leaking battery?

Ask Power Trac about your theory on the muffler and let us know. I would think that Kohler would make the muffler, or spec it out and test the engine with it. The muffler backpressure et al has a lot to due with the engine performance.

Duane

 

[marrt]

Duane,

Sorry for the delay in responding. I didn’t get a chance to ask PT about the new muffler yet. However, I’m still betting that my theory is correct. I noticed that this muffler is used in the 2425 with an insulated cover. I think this muffler likely stays cooler because it pulls air in from the outside and mixes it with the exhaust.

The rust on the muffler is not from the leaking battery. It’s from some water overspray I got on it.

This muffler has a very deep sound and I would bet it is quieter than the “standard” muffler. My only comparison is to the 422 I test drove at the factory. I think it is quieter than the 422 but that’s from memory only so I may not be true in reality. Also, if you look closely at the first attachment, you will notice that I have an exhaust leak on the right side (from the picture’s perspective). I may have to modify that side slightly as I suspect it is not perfectly parallel to the gasket.