Cat 3116 Breather Replace or Clean?

Boat Guy

Well-Known Member
May 15, 2013
2,289
Who knows? Could be Cali, Oahu, Florida, Annapolis
Boat Info
400 DA
Engines
CAT 3116s
Not sure exactly what to look for here... I've read they can be cleaned with "cleaner" but I'm not sure what to use nor how to do it on the boat without having a mess.

Is this something best to replace or do they last forever?

They seem to be oily but not rust or breakdown that I can see....I imagine a good flowing breather is important...yes?
 
Do you have Air-Seps or the OEM Caterpillar air cleaner? A dirty breather element restricts intake air flow and that is a primary contributor for transom soot.

AirSeps can and should be cleaned annually. You can order thew Walker kit from Walker Engineering, or buy a K&N filter kit at a local parts house. Look carefully at the element between the wire mesh and check to see if the paper is breaking down or crumbling. If in doubt, buy new elements from Walker. They are made by K&N but I think the Air-Sep sizes are only available from Walker Engineering.

If you have 20+ year old OEM Cat Elements, just buy new ones from Caterpillar.
 
Frank,

I have the std. Cat Elements, no AirSeps...on the air intake side...Just replaced the turbos and risers (fun job)

I'm just not sure on the "Engine Crankcase Breather - Clean" section where it says "Wash the breather element in solvent that is clean and nonflammable" What solvent would be good, non-flammable, and easy to do on the boat...Further, is there someway to determine if it needs to be replaced or do they last relatively forever?
 
Is this the one (#2 in the graphic), or one like it, that you’re talking about?
I’ve removed, cleaned with Simple Green, dried, reinstalled mine whenever I clean my Walker Air Sep and Vacuum Limiter Elements.
Just a couple of clamps.
The elements get cleaned with a K&N cleaning kit and re-oiled
Honestly though, the Breathers (#2) were clean the first time I did it when I got the boat and clean the couple of additional times I took them off for cleaning.
If you’re talking about elements: The previous owner of my boat had an extra set for each engine so I clean and re-oil them at home. You don’t want to be cleaning and oiling those things in the bilge unless you want a big mess.

8581CB48-1DA2-4482-B635-725FD1979C2A.png


Here is a graphic of my elements. Yours may be different:

3CDE16FA-E3A1-4778-A5CE-0F39768101A3.png
 
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Not sure exactly what to look for here... I've read they can be cleaned with "cleaner" but I'm not sure what to use nor how to do it on the boat without having a mess.

Is this something best to replace or do they last forever?

They seem to be oily but not rust or breakdown that I can see....I imagine a good flowing breather is important...yes?

I use Amazing Orange from the Dollar Store. I dilute it about 50/50. It's a great degreaser and inexpensive.
 
Yep, #2.... I already pulled them and looked inside...They are oily...not dirty, but oily.

I don't have Airseps...


Wait a minute..........

The picture you referenced saying you had the #2 set up is a diagram of an engine with Airseps.

The OEM Cat filter is foam that is surely dried out and brittle by now so you probably cannot successfully wash them. If you do have filter elements shaped like a truncated cone as shown in #2, then you do have AirSeps and you should be able to clean then with the Walker Engineering or K&N filter cleaning kit, which comes with a spray bottle of a degreaser that will not damage the filter as well as a bottle of the correct type of oil to redcoat the K&N element
 
Wait a minute..........

The picture you referenced saying you had the #2 set up is a diagram of an engine with Airseps.

The OEM Cat filter is foam that is surely dried out and brittle by now so you probably cannot successfully wash them. If you do have filter elements shaped like a truncated cone as shown in #2, then you do have AirSeps and you should be able to clean then with the Walker Engineering or K&N filter cleaning kit, which comes with a spray bottle of a degreaser that will not damage the filter as well as a bottle of the correct type of oil to redcoat the K&N element

I think he is talking about #2 (the breather) in the first graphic.
I only posted the second graphic of “what I have” to show the difference between the breather and elements.
Sorry for the confusion.
 
Yep, #2 in illustration 1....not the second image....I do know what AirSepts are, and look like...I don't have them. Thanks guys...The Cat filter element is in decent shape...The breather element is hard to see inside the housing and I just wanted to know the consensus...Replace / clean....Seems like you all just clean them...
 
Any degreaser should work.
Don’t remember mine being that messy. Yours may not have been cleaned for a very long time.
We’re you getting any soot or anything?
I’d probably soak those for a while, agitate with a soft brush like a paint brush or something, rinse then dry with compressed air.
 
I didn't know about taking off the breather and cleaning it, I do the AirSeps every year, along with Item #1 in the second image (not sure what that is..). If I'm reading this right, I can just unclamp the big white element and take it home to soak in a degreaser? To be sure, it's the item in red in my image, correct? I've been cleaning the 2 items in green already. If that can contribute to the sooting, I want to jump right on it!

CAT Breather.jpeg

Thanks,
Kevin
 
I didn't know about taking off the breather and cleaning it, I do the AirSeps every year, along with Item #1 in the second image (not sure what that is..). If I'm reading this right, I can just unclamp the big white element and take it home to soak in a degreaser? To be sure, it's the item in red in my image, correct? I've been cleaning the 2 items in green already. If that can contribute to the sooting, I want to jump right on it!

View attachment 71033

Thanks,
Kevin

#1 is called a vacuum regulator element. Like the air sep element, you can use a K&N filter cleaning kit to clean and re-oil both.
The thing that’s painted white is called a breather element. You can remove it, clean it with a non flammable degreaser, rinse, dry and re-install.
 
#1 is called a vacuum regulator element. Like the air sep element, you can use a K&N filter cleaning kit to clean and re-oil both.
The thing that’s painted white is called a breather element. You can remove it, clean it with a non flammable degreaser, rinse, dry and re-install.
Thanks for the explanation. I've been cleaning the AirSep and the vacuum regulator regularly, I'll add the breather element to the list of things to do. Really appreciate this forum!

Kevin
 
Thanks for the explanation. I've been cleaning the AirSep and the vacuum regulator regularly, I'll add the breather element to the list of things to do. Really appreciate this forum!

Kevin

Not sure if the breathers on your 3116’s are the exact same as the ones on my 3126’s. They probably are.
There are a kind of half tubular grip inside the bottom (bigger) clamps. Loosen them as much as you can and when you work the breathers off you’ll see what I mean.
Also, there is a rubber “O” ring that sits on the housing the breather connects to. It acts as a seal for the breather. I haven’t had to replace mine. They’ve been in good shape. Yours probably are too. But make sure you inspect them when you have the breathers off.
Once you have the breathers clean inside make sure you dry them completely before reinstalling. Blow them out with compressed air.
 
Thanks for the explanation. I've been cleaning the AirSep and the vacuum regulator regularly, I'll add the breather element to the list of things to do. Really appreciate this forum!

Kevin

How did you make out with the breathers?
 

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