What is purpose of rubber "duckbill"

[lmichael]

So on the air cleaner housing there is a rubber "duckbill" looking thing. When I bought my tractor it was ripped. I installed a new one and recently saw the new one is ripped. I hadn't even noticed it or noted any difference in the machine's performance. But, they seem to have a short lifespan so I bought 2. And will put a new one on next time I am out to use it.
But, what are they for? Does it really serve a purpose?

 

[Fordtech86]

Vacuator Valves Automatically Expel Dust Water | Donaldson Engine & Vehicle

Many Donaldson air cleaners are supplied with a small, wedge shaped, rubber valve called a Vacuator™ Valve, or ‘vac valve’. This simple device is often overlooked but is critical to the correct operation of the air cleaner.

www.donaldson.com

 

[Bmyers]

I think and I could be easily wrong, you are talking about the evacuator valve on the lid of the air cleaner.

My understanding it is faced towards the bottom when you put it on and it allows larger particles to be evacuated out of the system.

Edit: I see that Fordtech86 responded with what it is.

 

[SDT]

So on the air cleaner housing there is a rubber "duckbill" looking thing. When I bought my tractor it was ripped. I installed a new one and recently saw the new one is ripped. I hadn't even noticed it or noted any difference in the machine's performance. But, they seem to have a short lifespan so I bought 2. And will put a new one on next time I am out to use it.
But, what are they for? Does it really serve a purpose?

Squeeze from sides to allow debris to fall out.

 

[D2Cat]

It's (vacuator valve) a snug (interference fit) as it fits the airbox. On my wife's zero turn it came up missing. I couldn't find it anywhere, so I ordered a new one. Painted it orange and used a zip tie to anchor in there.

 

[lmichael]

Interesting read. Though for something seemingly so important I would think it would be made longer lasting LOL.

 

[SDT]

Interesting read. Though for something seemingly so important I would think it would be made longer lasting LOL.

Have one on each of my Kubotas.

Never any need to replace any, even the one bought new in 1993.

 

[Lil Foot]

Lots of things have them.
My Yamaha Rhino has one on the air cleaner box, and another on the cooling plenum for the drive belt.

 

[lugbolt]

when the engine stops, it sometimes "backs up" due to compression and valve spring pressures. When it does, the intake becomes the exhaust as some air is expelled when the engine turns backwards. During that short time some dirt and such is forced back out of that valve. That is the "idea" anyway, although I've never seen it actually work. But I admit, I have not watched for it either.

On the Rhino's and other off-road equipment, it's simply a one-way valve that is supposed to catch fluids, oil and/or air filter treatment oil, and is "supposed to" let those fluids out but not allow fluids (water) to get back in. They hold engine oil and air filter oil just fine but they never seem to really let those fluids out on their own, I always manually drained em during servicing.

 

[2001TLB]

So on the air cleaner housing there is a rubber "duckbill" looking thing. When I bought my tractor it was ripped. I installed a new one and recently saw the new one is ripped. I hadn't even noticed it or noted any difference in the machine's performance. But, they seem to have a short lifespan so I bought 2. And will put a new one on next time I am out to use it.
But, what are they for? Does it really serve a purpose?

I have always thought it was for draining water that may have accumulated.

 

[lmichael]

It's called a "dust ejector" but I failed to understand how it could "eject" anything

 

[D2Cat]

It's called a "dust ejector" but I failed to understand how it could "eject" anything

Go back to post #9. Or else just give it a squeeze when filling with fuel.

 

[JimmyJazz]

Neill from Messicks referenced this in one of his YouTube performances. Squeeze and jiggle out any large pieces that may have come into the intake but were not captured by the filter.

 

[cthomas]

Silverado diesels newish have them on the hood for the ram air system. Just crazy to see how many bugs come out when you squeeze it. Yes, it is disappointing to see how many people just ignore the vacuum valve when doing service on equipment.

 

[lmichael]

Go back to post #9. Or else just give it a squeeze when filling with fuel.

Oh I read it. Sort of get it.

 

[Nicfin36]

I have to replace the one on my zero turn every season. It essentially melts and turns into a bubblegum consistency. Poor material, poor placement, etc. The one on my L2501 still looks new.

 

[lmichael]

Mine simply "shredded". It was bad when I bought the machine (who knows for how long), so I replaced it. OEM part BTW from the dealer. Didn't pay attention to it, and just noticed it was bad last time I looked at the air filter about 10 days ago. This time I bought a 2 pack but non oem

 

[GeoHorn]

This evacuator-valve was damaged on my JD diesel compactor. I simply ordered a new one on Amazon. It states:

• The Donaldson Vacuator Valve Is Essential For The Proper Functioning Of The Air Cleaner. In Two-Stage Air Cleaners, This Valve Is A Vital Part Of The Pre-Cleaning Stage. Like The Other Donaldson Products, This Vacuator Valve Is Durably Constructed To Withstand Whatever The Environment Throws At Your Truck.

https://www.amazon.com/gp/product/B015YRHR9U/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
(Your size may differ…this was on mine.)

If you place your hand beneath the evacuator while the engine is running…you can feel a slight expulsion of air with each stroke of the engine. If you slightly squeeze the valve to open it slightly…dust, dirt, bugs, straw and any other foreign object inside will be expelled. This is something which should be done regularly.

If yours is damaged…simple….replace it.

 

[lmichael]

That's the plan. I bought a 2 pack