Scag 483841 MUFFLER

Dwellonroof

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Apr 23, 2018
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My 28 hp Cat diesel muffler broke at the bend in the bracket for the second time anyone else have a similar problem? I had it welded the first time.
Scag wants $357.80 for a new muffler!!!
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Born2Mow

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The fact that there is a flexible section of exhaust hose means that Scag knows there is a vibration issue. That stuff is EXPENSIVE and isn't added to an exhaust system simply to add "good looks" !!!

1. As I understand it.... the muffler mounts to the back plate on the mower, while the pipe mounts to the engine. Therefore you have a mount that's "3 generations" removed from the source. That is... motor mounts to the frame, frame mounts the back plate, back plate mounts the muffler. The break in the muffler could be a symptom that the back plate is not firmly mounted to the frame, or that the engine is not firmly bolted down.

2. It is also possible that the back plate is moving despite being firmly bolted to the frame. This happens when the "natural frequency" of the back plate matches one of the frequencies generated by the engine. In that case you may need to add rubber isolation mounts between the muffler and back plate to allow the muffler more flexibility. Lots of cars and motorcycles use this system. CLICK HERE. Simply replace the fasteners between the muffler and back plate with some of those rubber mounts.

Hope this helps.
 
Last edited:

slomo

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Just another reason why not to buy a Diesel. All the vibes and expensive maintenance parts. Better check all the wiring harnesses and tape them up good. Get some plastic loom if yours doesn't have it already.

slomo
 

bertsmobile1

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Weld it again and put in a brace plate or two at right angles to direction of the crack
In theory there should not be any movement between the engine & the frame , if the engine is bolted solid to the frame
So check the engine mount bolts are tight
I can not visualize the exact set up from the IPL but consider fitting thackery washers to one of the mountings so it can move without flexing the exhaust
PS Thackery washers are like a double split washer usually found between the rockers on car engines to allow a small amount of movement along the shaft .
 

Dwellonroof

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I have an older Hobart 150 wire welder so I welded it back but this time I put a bead on the inside of the bracket also. I'm not skilled at welding and it doesn't look the best but we will see how long it last this time around.
Also it bolts to the engine.
 
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