Lets Talk Air/Oil Seperators

I'm interested in getting an air/oil separator. I always thought they make a lot of sense especially for turbo engines. What are your thoughts? Can anyone recommend a brand?

Here is one i found from a quick google search:
https://www.jlosc.com/j-l-oil-separator-3-0-driver-side-2022-toyota-tundra-3-5l/

 

I have the same brand and it seems to work just as good as the more expensive ones like Radium based on what it has collected compared to others I’ve seen posted. I’ve had one for probably 5-7k miles and I’ve collected about 1/3 of a 16oz. water bottle of oily slime.

I like it since it can’t hurt to help prevent sludge buildup on valves, and in my case keep oil off the SC intercooler brick. The oil vapor that gets pulled into the intake without one can reduce the effective octane rating of your fuel and lead to power cutting knock retard as well. I’d just be cautious on a new truck due to the warranty, they will blame an engine failure on anything aftermarket even if it actually helps the engine.

 

I just got the one from Burger Tuning. Hoping to install it this coming weekend! Seems to be built really well.

 

You're already working on a 23 limited tundra?? I'd spend that money on a deer rifle or boolets

 

Is this really necessary? The V35A incorporates both port and direct injection. Keeps the valves clean by washing the backside. Any other advantages to adding a separator? Wouldn’t Toyota add one if fuel dilution was an issue?

 

I wouldn’t call it absolutely necessary. It certainly won’t hurt either way to have less slime in the intake manifold, throttle body, valves etc. As for Toyota adding one, some people can’t even remember to change their oil on time let alone empty a catch can on occasion. Failure to empty it over a long period could result in it filling up and the sending a big slug of oil into the intake. In that case it would do more harm than good. They’re not going to install one from the factory for mainly that reason alone, not to mention you’ll never notice some minimal knock retard from oil vapor, or experience any other issues within the warranty period from not having it.

 

If the PCV system is anything like the Ecoboost, and you truly want this to work then you really need to run dual cans. The engine likely has two PCV flow paths for when the manifold is in vacuum or when its in boost.

When in vacuum there is likely a hose running from one of the heads to the manifold. When the manifold pressurizes a check valve likely closes to prevent pressurizing of the crank case, and then crank case gasses are likely vented into the intake before one of the turbos. This provides a small amount of vacuum while in boost due to the turbo pulling air against the intake filter.

So in one scenario, PCV gases are going straight to the manifold, and in the other the pcv gasses are going into the intake, through the turbo, through the intercooler, through the throttle body and into the manifold. In the boost scenario the gases are probably going to condense out in the intercooler.

 

The V35A definitely has an air-oil separator from the factory.


this is an example of the one from the LS500 with dual throttle bodies but it should be the same layout for pcv.

 

I think that is an internal oil separator for CCV, not PCV. It would not be beneficial to have a CCV catchcan, but a PCV catchcan would probably catch some junk. Unless that is somehow doing both?

 

CCV and PCV are the same thing. The air oil separator is between the crank case and the pcv valve and its intention is to catch whatever oily junk. It’s not as good as a catch can though but I think this engine doesn’t need it due to dual injection.

 

My understanding is that CCV and PCV do the same job, but differently. CCV is not a valve but an orifice that allows a constant limited flow of crankcase gas to be pulled into the intake. The PCV is a one way valve that opens when the manifold pressure drops such as when the throttle opens. The 3UR for example has an internal oil separator as well for the CCV side, but not for the PCV. When people install a catchcan on the CCV side it doesn’t catch anything, but the PCV side catches a lot. Perhaps the V35 does in fact utilize an internal oil separator that filters out the vapor for both the CCV and PCV, but I don’t know. That drawing kind of makes it look that way? I guess it depends on if their PCV nomenclature is correct on the drawing or if that should actually be labeled CCV.

 

I’m with you in this, but it also couldn’t hurt to install one on the dirty side, I did this on my Ecoboost

 

The Dirty side depends on how much you are in boost on an Ecoboost. Due to my elevation, my engine is almost always above ambient pressure and so my dirty side is the drivers side. and then 50% of my miles are towing which means constant boost.

I had a separate can for each side and caught very little on the passenger side.

 

Does it really come up from the center of the block into the bottom of the manifold? Seems unnecessarily annoying and difficult to access if the PCV were to have an issue.

I also dont see the turbos in this diagram. Do the lines labeled 10 and 11 leave the intake after the turbos, so they are pressurized to the same pressure as the charge air? Wouldnt that mean the crank case was pressurized?

 

nothing out of the ordinary having the pcv there...LS6 engines had it back in the day...very easy to service

 

Sure, if its just a simple barb. That diagram makes it look like a fixed connection under the manifold with a "catch can" and PCV stuffed in there.

an SBC is also a very simple setup compared to a turbo motor that needs to be able to have a functional PCV while the manifold is under both vacuum and boost. Its not really comparable.

 

The Tundra has a single TB after the intercooler. If they still have the system setup like this though, a catchcan would be virtually useless.

 

I guess it’s under the intake manifold in the vee. I can’t tell from this image.


From what I can tell, #10 ventilation hose in the previous images that goes to the valve cover is before the the turbo so it’ll make vacuum at high boost. The diagram is definitely missing the turbos.
Finally, here is our engine’s layout with single throttle body.

 

the best post in this thread by wide margin.

 

Just ordered the j&l Osc oil seperator..will post pics and thoughts when I get it..always have install a catch can on all my cars...

 

So, how PCV works under boost, when it is needed the most?

 

Yeah the first diagram that was posted has to be wrong otherwise they would be feeding thr crank case 15 psi