Is something missing from my air intake

JeepinMaxx

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I was going over some of the maintenance interval stuff in my BX2660 manual since I'm approaching a 400 hr service. On the air filter page I saw something called the "evacuator valve" that is supposed to be checked often



So curiously I checked mine and it looks like it's missing...



What is the function of this "evacuator valve" ? Looks like the rubber drain on my old ATV's air filter box...

Should I be concerned that it's missing?
 

D2Cat

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Here's the answer I copy and pasted from Donaldson's Site.

The Vacuator Valve, standard on the majority of Donaldson air cleaners, is an important part of the functionality of the air cleaner. It is an integral part of the pre-cleaning stage on two-stage air cleaners. The dust cup, where pre-cleaned dust is collected, is normally under a slight vacuum when the engine is running. The normal engine pulsing of the vacuum causes the Vacuator Valve to open and close. This action automatically expels any collected dust and water. The Vacuator Valve also unloads when the engine is stopped
 

mickeyd

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Without that valve being there, there is NO way for it to close.

I would replace it just to ensure that it worked properly. Kubota would not have paid to put it there if it did not have a purpose.
 

rjcorazza

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I personally would replace it. It's supposed to allow larger ingested dirt particles to become trapped and subsequently released by squeezing it. Likely most stuff just gets ejected without user intervention, as I have never seen anything come out when I mess with it.


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lugbolt

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LOL y'all don't know how it works?

The end of the nipple (farthest from the cleaner) has two lips that kinda make a one-way valve. When the engine is turned off it keeps spinning, although it does slow down. When it slows down to a point where engine compression stops it from turning, it will back up and turn backwards briefly. Don't believe me? Watch the fan next time you shut 'er down. Anyway, when the engine turns backwards, the intake valve becomes an exhaust valve of sorts, expelling some air. That air backs up the intake tract, through the air filter and blows the loose dirt/dust/stuff out of that little nipple on the filter.

It's not critical. Many are missing and the worst that happens is that the filter gets dirtier quicker.
 

D2Cat

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Lugbolt, that is just a rubber boot with the "lips" you mentioned. There is nothing inside it that spins(other than air). What are you referring to? I need to learn something today.
 

SidecarFlip

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LOL y'all don't know how it works?

The end of the nipple (farthest from the cleaner) has two lips that kinda make a one-way valve. When the engine is turned off it keeps spinning, although it does slow down. When it slows down to a point where engine compression stops it from turning, it will back up and turn backwards briefly. Don't believe me? Watch the fan next time you shut 'er down. Anyway, when the engine turns backwards, the intake valve becomes an exhaust valve of sorts, expelling some air. That air backs up the intake tract, through the air filter and blows the loose dirt/dust/stuff out of that little nipple on the filter.

It's not critical. Many are missing and the worst that happens is that the filter gets dirtier quicker.
Bingo.........
 

Russell King

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Lugbolt, that is just a rubber boot with the "lips" you mentioned. There is nothing inside it that spins(other than air). What are you referring to? I need to learn something today.

He means the engine as I understand what is spinning.


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85Hokie

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He means the engine as I understand what is spinning.


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And spinning backwards after "stopping" - thus producing a small backwards air pressure into the intake of the air filter.....

and with that little puff......and heavy dirt particles are blown out.

Quite ingenious I might add!:D

Lesson learned! D2....aint it good to learn sumthin new every day? I learn something without even trying hard!
 

JeepinMaxx

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Thanks for the feed back on my question! I'll probably pick up a replacement, but in the last two 50HR air filter changes, it hasn't been dirty at all - just replaced it anyway. Sounds like "rubber boot with lips" that I mentioned was on my ATV air box (and now that I think about it - on my fridge condensate drain!)
 

JeepinMaxx

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Thanks for the input! Stopped by my local Kubota dealer on my way home from lunch today. Around $8