Exhaust Mod on my 3725

[Slowpoke Slim]

Eddie,

To answer your question, "it fit" the space I had available. I needed a short, fat muffler. This was attempt #3, as the first one was too small in the body, exhaust guy thought I needed bigger chamber, so I looked at an IH-6, but the inlet and outlet pipes were too big around, this IH-4 was "just right". Met the size for volume and for length that we were looking for.

 

[YanmarFever]

I have to run my 4520R at an idle for a few hours at a time while I spray Iron in our fruit groves and the dpf light is on.
Does anyone have a picture of the dpf gut removal from their machine?
I really need to remove this soon, the machine has 71 hrs on it
Thanks Ernie

 

[abranz]

With a 2020-2021 3620 you loose the dash temp and tach function. I was doing some work on it and started the engine without the data logger and cat-dpf plugged in. Wiring must have changed in the newer models.

 

[Cougsfan]

On my 4720ch, when I lost my tach it was because the alternator failed. What it does is count the ac waves generated and converts it to engine rpm by multiplying it times the gear ratio of the engine to the alternator. Not sure if yours is the same.

 

[ptsg]

Wondering if they started combining the wiring harness for the engine and the DPF on the same plug.

 

[abranz]

Alternator is fine. Plugged everything back in and gauges work normal after realizing I had forgot to do so.

 

[Slowpoke Slim]

Thanks for the heads up abranz, that is some important information we'll have to let folks know.

Now the trick is going to be if someone with the later wiring harness can figure out the pinout to wire in a bypass.

 

[K5lwq]

That is interesting. Maybe it will be simple to figure out once the wiring diagram is released. But one could just leave the data logger plugged in and ignore the light.

 

[Slowpoke Slim]

Is it only the data logger plug that needs reconnected abranz? Or is it more of the harness that connects the sensors to the DPF cannister?

Because yeah, if it's only the data logger plug, that won't hurt anything, but the dpf light will stay lit on the dash.

 

[abranz]

I’m not sure. The data logger and dpf sensors were all disconnected until I realized my mistake.