Noise after turning off engine

[BeezFun]

My friend has a new DK6020. When he turns it off there is a noise that lasts a few seconds and sounds like the air blending door moving on a car's heating system. I used a stethoscope to try to figure out where it's coming from, I think it's the silver aluminum thing in the upper left part of the photo, which I assume is the electronic control board since it has large numbers of wires coming in and it's a heat sink. It could also be the DPF which is in the upper right of the photo. Does anyone know what this noise is and if it's normal? He does have a cab with heat/AC, but the noise doesn't seem to be in the cab, it sounds like it's in the engine compartment.

 

[RjCorazza]

Electric lift pumps can continue running for a few seconds after shut down, are you certain that is not the cause?
If it has an electric lift pump, it will be rhythmic ticking sound and easy to confirm with your hand on it.

 

[BeezFun]

Electric lift pumps can continue running for a few seconds after shut down, are you certain that is not the cause?
If it has an electric lift pump, it will be rhythmic ticking sound and easy to confirm with your hand on it.

It's not rhythmic or ticking at all, I'm familiar with the sound of electric pumps. It sounds more like vacuum moving a door, or some kind of baffle. Does the DPF have anything in it that moves to redirect hot gases? I wouldn't expect it to be doing anything unless it's regenning, but just guessing.

 

[toxicjeeper]

I have an ns5310 and mine makes the exact same nosie on shut down...I never thought much of it tho as long as the tractor works fine...I kinda thought it might be the dpf dumping ash out or something but I don't really know.

 

[toxicjeeper]

Also I have no cab and park inside my shop so I really hear it on shut down..lol

 

[ptsg]

These common rail engines use what they call "air control valve" to control the amount of air it gets. It's just like a throttle body on a gas engine.

What you hear, is most likely this valve getting back to open position. As you shut down the engine, the valve closes and then opens back up.

 

[BeezFun]

I have an ns5310 and mine makes the exact same nosie on shut down...I never thought much of it tho as long as the tractor works fine...I kinda thought it might be the dpf dumping ash out or something but I don't really know.

Thanks, it doesn't seem like a bad noise. I was just curious what it is.

 

[BeezFun]

These common rail engines use what they call "air control valve" to control the amount of air it gets. It's just like a throttle body on a gas engine.

What you hear, is most likely this valve getting back to open position. As you shut down the engine, the valve closes and then opens back up.

Thanks, I'll try putting my stethoscope near there next time to see if that's it.