air intake silencer

[Pete G]

Now that the boat is on the hard, I've started digging into engine maintenance, which the PO seemed to think of as optional.  I discovered that the air intake was not attached, and was laying next to the engine.  (sign).  Pic attached.  From looking at previous threads, I know this is the "OG" intake for the Universal 25 (301138   Air Intake Silencer).  Is there an upgrade path?  I see the part that is for later engines, but not sure if this is a swap or if a housing is still needed (302181   Air W/Foam Cover Filter).  Pic of mine, with random surgery.

[Noah]

Search the term "breather". Lots here.

[KWKloeber]

Pete

There were two different ones - the coffee can below (*appears* to be your left, bottom half) and horn style (right, top half?).
There is a KN option which I've never used (doesn't fit my C30 engine compartment.)
Regardless which way you go be sure to run the crankcase breather hose (top of valve cover) to the intake.
There's several ways to do it - see the TechWiki > Engine or here:
https://groups.io/g/Catalina30/wiki/26707
You can also carefully drill/tap the intake manifold for a hose barb.

[Ron Hill]

Pete : From what I've seen, your type air cleaner filter was only on 1987 (1986?) C34s.  Not shown is that your air cleaner also had a tapered  "snoot" attached.

Then "Oshkosh" changed in 1988 for the M25XP, to the "Can type" that Ken has shown in the above post.  That can type has stainless oiled "shavings" on the inside and a foam "silencer" around the outside.

A thought

[Pete G]

Good tip - I was planning on removing the intake manifold for cleaning, anyway.  Part ordered.  VW Beetle air cleaner elements fit in the existing housing.  Anyone have a good reason not to use one?  They're far less expensive.  https://www.jbugs.com/product/9048.html

[Ron Hill]

Pete : I'd go with the VW filter!!  The inside of the engine compartment is NOT "dusty".  You can adapt the oil pan vet so it exhausts in to your aircleaner!!

A thought

[Pete G]

The VW air filter fit perfectly into the housing.  I'm on the fence about drilling a hole into the manifold vs. clamping the breather hose nearby vs. adding a "spigot" to the filter surround if I can bring that back to life.  All winter to ponder, at this point - snowing today.  I could have used another day on the boat! and then another, and another, and another...

[Stu Jackson]

There is absolutely no need or reason to drill any hole in the manifold.

From the 101 Topics:

Breather Hose 101 (w/ K&N Filter Pictures from Rick Allen)

http://c34.org/bbs/index.php/topic,8875.msg63915.html#msg63915

and Noah's:  http://c34.org/bbs/index.php/topic,8858.msg64297.html#msg64297

and Kloeber's PDF and wiki link:  https://c34.org/bbs/index.php/topic,8136.0.html

[KWKloeber]

@Stu,
Except that on his xp? he is not using those coffee can or KN assemblies, so those alternate methods (though not impossible) are a tad more persnickety to install (and he said that he'd have the manifold off anyway, although the hose barb can be stalled in situ.)

Direct to the manifold is how it is on some, not all, of the current Kb tractor engines.  Wb just did not spec for Kb to supply that manifold with the hose nipple on it for the breather hose. However, the "B" manifolds DO have the knockout for it.

[Stu Jackson]

@Stu,
Except that on his xp? he is not using those coffee can or KN assemblies, so those alternate methods (though not impossible) are a tad more persnickety to install

However, the "B" manifolds DO have the knockout for it.

Kren,

He's got hull #371, a 1986 boat (like mine) which means he's most likely got an M25.  He also said "Universal 25 engine."  So I don't know where either XP or B comes into any of this.

What would be "persnickety to install?"

Just trying to understand.

[KWKloeber]

Stu

Yep, I missed Pete's callout on his model but 25 or xp is irrelevant.

He's not changing to the KN, so that method w/ the add on hose nipple doesn't apply here. 
And that add-on nipple can't be used on his assembly.

He doesn't have the coffee can, so, strictly speaking, the method(s) in my pdf don't apply. 

Pete has the "horn" type assembly which, as I said can be done, but is in my mind more difficult when (just like example I provided) Kubota runs it right to the manifold and he's removing the manifold anyway.

My comments about the "B" engines (admittedly not clearly made) was that running the breather into a manifold barb is how Kubota does it on some of its current engines — so it's not an off-the-wall idea.   I believe Kb is doing it where the application requires capturing the gunk rather than dumping it to open air (dunno, but it might be due to emissions restrictions as well.)
My point was simply that "good enough for the Kb factory" is good enuf for our older engines and it's easy to do - at least as easy and I'd argue easier than the other methods and can be done with the manifold on the engine.   Drill; tap; screw in a barb; voila' easy peazy.

The info about the "Bs" was also in there to alert those owners who may read this that there is already a knockout provided for their breather hose (vs Wb's stupid cut-off, zip-tied-in-place method.)

I suppose with Pete's type I'd think about a barb right into the side or top of the horn if that's the approach. 

Different ways to skin a "Cat" and the same statement could apply - "absolutely no reason to drill and
cobb fittings onto the intake assembly" (vs a tapped hole in another location.)

[Pete G]

To clarify, I removed the intake manifold but am replacing it with the same intake manifold.  I could drill the hole, but why directly into the intake? 

P.O. ran the boat with no air cleaner housing and no dipstick.  You'll also notice the broken bracket for the heat exchanger in the back.  You can see the fixed bracket and the tip of the exchanger in the 3rd pic with P.O.'s mysterious "modification" to the horn intake surround. 

This might be the easiest path: https://www.jbugs.com/product/8674.html

[Noah]

No dipstick must have bern a disaster?

[KWKloeber]

Pete

Now you've got me completely cornfuzed.  I thought you intended to try and salvage the "horn" housing.  As I explained (first post) you have parts of two different assemblies there.  If you're going to use the coffee can then, sure, you can put a hose barb on it — or use the KN hose nipple addspter, or a barb on the manifold.

I suggest that you add the foam silencer/prefilter if you use the coffee can.

The vw one looks odd in that you'd need to route the hose dpwn to the bottom. If you're buying a new assembly (no need to) why not get a KN?

Personally I like the hole/rubber grommet/hose barb elbow

[Pete G]

Not sure what the cause of the confusion is.  Here's a pic of another m25xp with the same air intake: