Oil Catch Can, Eliminate that knock!

I finished off my oil catch can replumb today. Basically going from 3/8" ID hoses to 1/2", which necessitated replacement of the fittings on the (Moroso) can. I also abandoned use of the OEM PCV hose (cut in half), used a couple of 90 deg brass elbows/menders, one going from 1/2" to 3/8" (at the PCV valve) and the other going from 1/2" to 3/4" (at the intake spigot).

At the barb connections (all but the two ends) I used no hose clamps. From what I've read it's not necessary, might even be detrimental to the hose. At the pcv valve and intake spigot I did use airplane clamps (aka worm gear clamps), but I just snugged them down, enough that the clamp seemed solid, couldn't be twisted. I kept those end runs of hose (3/8" and 3/4" ID's) just long enough for the two sides of the connection, virtually no gap.

I went pretty much full-Monty: removed the intake manifold completely, cleaned it with brake cleaner. Used this straw cleaner brush (long, skinny brush for cleaning reusable drinking straws) on the EGR passages. A surprising amount of barf came out of the intake, considering it's only been about 15K kms since last time. Also went over the intake ports (on cylinder head) with brake cleaner on a shop cloth.

Also, removed the pcv valve, cleaned its innards with carb cleaner, cleaned the threads (both sides) with brake cleaner, then reinstalled the valve with Permatex ThreadLock 243 (medium stength per 242, but better adhesion if there's a little oil residue).

The Moroso can I completely disassembled, pulled out the steel wire mesh wheaties, cleaned everything with brake cleaner, paying special attention to the threads. On reassemble all the NPT fittings got threadlock, and I replaced the 90 degree stock drain spigot with a similar but straight one. The two original 3/8" NPT to 3/8" hose barb elbows were replace with similar, except 1/2" hose barb. I notice the ID on the NPT side was greater on the new ones too, even though they're both 3/8" NPT.

Cutting the new hoses (3/8", 1/2" and 3/4") was stressful. Put the hose in position, measure m twice, initially cut at least an inch longer than you think you need, then fine tune.

Also gave the throttle body a quick clean with carb cleaner on a shop cloth. And the MAP sensor got a MAF sensor spray clean.

Didn't take a lot of pics, too busy, wearing grubby nitrile gloves, and it's cold, wanted to get done. Didn't get any pics of the new plumbing, but trust me, it looks serious lol.

Difference between 3/8" and 1/2" hose:


Workbench:
A couple of pics, before the replumb. Note throttle body has coolant lines still attached, no need to disconnect. Moroso can is down there, mounted on lower cross beam. For anyone thinking to mount thus, put some sort of rubber washers or gasket in the connection, so the beam can flex. It's the front jacking point, for one thing:
Crud from the intake manifold, after only 15K kms:

I recently added an extra baffle inside my Moroso can, hopefully that'll improve it's catch percent. Also, bigger diameter hoses maybe slows the air flow speed, which should help?

 

I think that nuclear reactors receive less strenuous maintenance....

 

Nice work.

With larger ID tubing, you should have less velocity but could have more flow (less back pressure).

As long as the added baffle doesn't dip too low in the can to cause liquid entrainment choking air flow, the steel wool will help with residence time as it has been.

The PCV valve is a 1/2" ID opening?

Good work though.

 

Nice watch

 

Even if your OCC were 100% efficient (of course it can't be), you would still get some oil in the IM on an Atkinson engine. By design, there is an oil film on the cylinder wall. Some of that oil will get atomized, some of it will be blown back in the IM.

 

Great job Mendel! Do you have to replace the IM gasket when you clean it or is it still in good shape?

 

Yeah I know, a chain is only as strong as it's weakest link, lol. Still, I suspect regardless of a local pinch point, increasing the cross-section area for the majority helps.

I'm curious, as an example, why the spigot on the intake manifold for the pcv hose is 3/4" size, when the hose is is 3/8". It's like they're trying to slow down the flow as it reaches the IM?

Yeah I think that baffle IS helping. There was quite a bit of goop, considering I just put the baffle in a few weeks back. With the Moroso can design, I think there's a propensity for the air flow to come out of the inlet side "wheatie", and just turn the corner, go straight into the outlet side "wheatie". The additional baffle forces it to head down, and a lip on the bottom corner deflects it even more, puts a spin on it.

Hey that's my theory, lol.

Regarding the incursion into the catch cup, possible clog-up if the can gets too full: at first I cut the baffle to be almost the full width of the can interior. Then, thinking about the clog-up factor, I trimmed the ends of the baffle, so there's at least 1/4" clear each end. That way I think even if the captured fluid level rose to the low edge of the baffle, there'd still be sufficient airflow, around the two ends of the baffle.

Here's some food-for-thought, for anyone looking to mount an oil catch can low, there's a blank plate bolted on the engine end of the transaxle (in lieu of starter motor?). Maybe a oil catch can bracket could hitchhike on that?



(Diptstick tube highlighted also, to help orient the pic.)

I've got a vague recollection someone recently did use those bolts, back a page or two here??

No I didn't. We're low miles though, only 85K kms. EGR and Intake were previously done around 70K, and I just figured I might as well take the intake off for this hose revision, and give it a clean out.

But more miles, not a bad idea to replace all the flexible gaskets. There's three: at the intake ports, EGR pipe, and throttle body.

I did pull them off, carefully clean/iinspect, and clean the grooves they sit in.

 

You could put TWO OCC's in series, that should catch more oil.

 

I have two Moroso cans (long story). And you do see some dual can setups. But meh...

I'm still trying to convince my son he needs one on his (direct injected) CX-5, other'n that not sure what I'll do with it. Likely will hang onto it, think of something.

I toyed with the dual can idea. But room is limited, and I decided it was getting a little nuts. Yeah, even for me...

I do think the added baffle is improving the catch ratio. Some info on that:

Oil Catch Can, Eliminate that knock! | Page 77 | PriusChat

Final version, baffle ends trimmed back, to ensure air flow still possible if captured fluid rises extra high

Oil Catch Can, Eliminate that knock! | Page 77 | PriusChat

 

Okay, LONG hose the the fender well....

 

Okay, LONG hose the the fender well....

 

Did the can come with the steel wool, or did you add it?

Anything special about what you bought? As I mentioned, I saw some steel wool in a hardware store but I’m concerned that small bits could get sucked into the intake manifold.

 

that's what I have, & the second one gets hardly nething in the summer, but enough to justify its existence in the winter /

 

you rather use this copper mesh ones here



"Copper scrubbers are catalytic to hydrocarbon breakdown, particularly in the presence of water vapor which is often present in PCV fumes. So if you use copper, the fumes and spray are "cracked" down to lighter hydrocarbons which burn easy."

 

I'd hesitate before putting anything in the engine intake that can rust and shed small particles that get sucked into the engine - especially copper.

It would be safer to condense more oily PCV vapors by cooling the can. My OCC is positioned near the intake air flow. It collects a lot of sludge in the winter months.

 

What do you put in for baffle in your catch can?

 

If you're improvising, I don't think you could go far wrong with something like bare copper grounding wire. Make a snarl of it and push it in.

My Moroso's wheaties are some sort of woven steel mesh I think:



And roughly life-size:


(roughly 2" in the longer direction)

 

I don't and it fills up quickly.

Are you baffled (bewildered)?

 

Which can?

 

The Ruien - see my sig.