Oil Catch Can, Eliminate that knock!

Mendel, we well know you have dual top OCC installed and drain certain amount water and oil. Do you find any oil down on the throttle body with dual OCC installed

 

Still some, yes. It’s a fine mist delivered by the PCV; an Oil Catch Can waylays a good amount of it, but it’s not perfect. Mine are Moroso, pricey but fairly simple. Some high end ones have complex baffles plus a filter on the exit; maybe more efficient.

 

Has any one move the PCV to upper location and in vertical position just this and no OCC?

 

An earlier post mentioned that the catch can (universal one from Amazon that most people use) came with a fitting that has the same threads as the stock PCV valve, and one person had used that fitting to relocate the PCV upstream to a vertical position.

If that's true, and the fitting threads into the stock PCV location, then it would stand to reason the PCV would thread into the outlet of the catch can. If that's true, would it make sense to thread the PCV directly into the outlet of the catch can? This would reposition the PCV and also filter the oil out before it hits the PCV which would keep it cleaner.

I read through about 50 pages of this thread and haven't found an answer to this question, so I apologize in advance if it's been answered.

Thanks!!

 

Can confirm that on my generic catch can I got from HybridPit for a stealth install has the same size threading as the stock PCV valve. Don't have a way to measure the threading at home but when I go to the hardware store to get some other fittings I can take it to measure it.

Not sure on the theory about move it from the stock location to the catch can outlet. Its just like a one-way check valve so air/oil can only flow out the engine but not get sucked back in. If you move it to your catch can outlet, there is a chance the contents of the can could get sucked in the reverse way.

 

It looks like the stock PCV valve is 3/8" brass fitting size.

Instead of cutting the stock hose and using male/male barb couplers with twice the hose clamps, I plan to just run 1 continuous hose line for each side to keep it simple. That meant I had to find some larger fittings to use on the catch can outlet so I can get some large diameter hose to go directly to the intake manifold side. Quick trip to Home Depot and found various options that would go from 3/8" on the catch can side to larger outlet that would have a snug fit with a hose clamp. I wasn't able to find barbed fittings but 1/2" outside thread seems to give it a snug fit. Last just need to get some hydraulic / fuel hose that I can run directly from the catch can to the intake manifold side.

PXL_20210619_203615072 by amarino posted Jun 19, 2021 at 7:52 PM

PXL_20210619_203644355 by amarino posted Jun 19, 2021 at 7:52 PM

Another option:

PXL_20210619_203901195 by amarino posted Jun 19, 2021 at 7:52 PM

PXL_20210619_203925837 by amarino posted Jun 19, 2021 at 7:52 PM

Stock PCV valve goes smoothly on the 3/8" side of this fitting just hand tight.

PXL_20210619_204027665 by amarino posted Jun 19, 2021 at 7:52 PM

 

The hose coming out of intake manifold needs to elbow very close, due to something adjacent. I’ve been there, tried something similar (with some variation), went back to @danlatu (OP) method.

One thing too, you don’t need clamps with hose pushed onto barb connectors.

 

Thanks for the first hand tips. I haven't been under to look at it yet and I'm renting lift time at a local DIY place for my upcoming oil change and install the catch can so spending 10x time researching so I can get everything done in one shot. Browsed through all 100+ pages, saved all helpful pictures offline, and I thought I could make the hose bend in one shot but we'll see.

As you can see I already have another hose as a spare (only $10 from the dealer) so I'll pick up some barb couplers as a backup if I end up cutting the stock hose for the 90* elbow, and whatever I don't end up using just return.

 

Some have used PEX connectors, which are grippy enough, but are easier to pull apart if need be. I couldn’t find them nearby. What I did with barb splice connectors (the most aggressively barbed ones) was chuck them gently in my drill press, and while they spun just slightly knocked the sharp edges of the barb. Not too much; a slight blunting is all that’s needed.

I use 3/8” fuel line SAE30R7, come from can to splicer, then from splicer to cut-half of orig EGR hose. Unclamped, which is still well sealed with multiple barbs, but the cut hose end elbows can swivel easily on the barbs, find it’s best angle.

I do retain and use the two orig spring clamps, at the cut hose connections, at PCV valve and intake manifold.

intake manifold torque values in attached:

 

Ended up just cutting my stock PCV hose and using the barb connectors to splice them together like everyone else. Also got some 90 degree barb fittings to keep it nice and tidy. Was a pain to install without taking off the intake manifold but got it done. Mounted in the starter hole cover with the HybridPit setup.

The HV connector for the A/C is in the way trying to get your hands in there but you can unclip it from its mount (but leaving the wires connected together)

 

I like the absence of clamps: those barbs are all you need. OTOH I’d sub SAE30R7 (or R6) fuel line (black) when you can, holds up better.

Like the elbows too. I’ve found a local hose connector “candy store”, has everything under the sun, and a good website:

https://www.new-line.com/

There’s also swivel elbows, so you’re not reliant on rotation of the pipe thread joint. One thing I found that makes regular elbows more flexible on how tight they need be, is generous layer of silicon pipe sealing tape; makes for a “soft landing”, when you’re tightening.

 

Here is where i placed my OCC, its lower then PCV valve and quite easily accessible (need to remove air filter box) to empty it. But mine has a dipstick, so i can check level without removing air filter box. And hoses are short which i think is better. I made a bracket and screwed it under air filter box with the same screw that holds the box.

 

Very clean install! Looks much better than all those hose clamps in the video I watched. Think I'm gonna copy you with the barbs, though I will probably still be putting the can up high like the others so disassembly isn't required to drain it.

 

Does anyone else find that their car stinks a lot more after installing the OCC? I find that generally there is that stinky exhaust/oil smell when around the car (same smell as the stuff you dump out of the catch can). Obviously vapors are escaping from somewhere in my OCC system, but I dont think I have any major leaks as everything is running fine.

 

Most likely a leak somewhere in your work but if a line is pinched, clogged or the occ is full or stopped up, back pressure could be forcing blowby out of some engine seal. The potential of an occ filling up is a big reason manufacturers don't factory install them. Some that do use an automatic drain back to the crankcase. One of the weak points that could be impacted by back pressure is the timing chain cover.

 

Is the OCC worthwhile on a 280k Prius? I have the warm engine knock and coolant loss.

 

Never too late, but don’t pin your hopes on it.

 

lol all I need is a miracle. I am planning to do the plugs and injectors as well. The EGR circuit was already unplugged so wasn’t sure if the OCC would be worthwhile at this point.

 

Yeah you’ve got bigger fish to fry, have knocking? Leak down test?

 

It's knocking for 30 seconds to a minute when the engine is warm and when I restart it and take off. I've lost some anti-freeze, but nothing external.