JLT Oil Separator and Catch Can – Complete Step By Step Install and Review
*** As of early 2022, JLT Performance is now call J&L Oil Separator Company. ***
What is the purpose of an Oil Separator you ask?
To understand what we need to understand why. When the engine goes through the suck, squeeze, bang, blow cycle process, that’s known as the “combustion cycle”. With this combustion cycle, combustion gasses, gas, and oil get passed over the piston rings and into the crankcase.
This phenomenon is known as “blow-by” or blow-by gases. Now the pressure will eventually build up in the crankcase from the blow-by, and eventually, this pressure will have to be vented somewhere and this is where the Positive Crankcase Ventilation (PCV) valve comes in.
The PCV valve vents the blow-by from the crankcase into the intake manifold to be fed back into the combustion chamber to be burned off. The PCV valve does this so that these blow-by gases don’t mix with the oil, causing sludge build-up and oil degradation over time. One of the problems with the PCV system is that the oil and unspent fuel will eventually build up in the intake valves and over time reduce engine efficiency. Basically, the PCV valve doesn’t catch everything. It’s designed to catch a lot of blow-by gasses but misses quite a bit over time.
This is where the JLT Oil Separator comes in.
Find It Online:
- J&L Oil Separator (Model 3107D): Check Price
JLT Catch Can Install and Overview
JLT 3.0 Oil Separator
The JLT Oil Separator sits between the PCV valve and the intake manifold. It consists of two parts: the filter housing and the oil catch can.
JLT Oil Separator Features
- 3oz capacity
- Machined from billet aluminum
- Multi-stage filter system
- Made in the USA
The filter housing filters the blow-by from the PCV valve through a fine mesh stainless steel screen that traps the oil vapor so it condenses into tiny oil droplets and in turn gathers into a bigger droplet in an aluminum honeycomb filter below.
Once the droplets are large enough, it then falls into the oil catch can. Meanwhile, the gasses from the blow-by are passed back into the intake manifold without the sludge building oil and fuel.
What’s in the Box?
What’s Included
- JLT Oil Separator (aka catch can)
- Mounting bracket and M4 screws
- PCV valve hose (Long)
- Intake manifold hose (Short)
Tools & Materials:
- 10mm deep socket and ratchet
- Phillips screwdriver
- Grease
- Painter’s tape
Step 1. Remove Plastic Engine Cover
Pretty simple start, lift up on the plastic engine cover and then pull it towards you.
Step 2. Locate and Remove the PCV Hose
With the cover removed, locate the PCV hose on the driver’s side of the engine. The PCV hose is connected to the intake manifold and the PCV valve on the valve cover. Locate the two spring clips at both ends of the hose and slide them towards the center of the hose. Once the spring clips are no longer clamping down on the connectors, gently pull and remove the hose from their connectors.
The PCV valve on the valve cover is harder to get to, but if you follow the hose from the intake manifold side, it should be right there.
Step 3. Install PCV Valve and Intake Manifold Hoses
Remove both spring clips from the PCV hose and transfer them to the short section of the PCV Valve Hose and Intake Manifold Hose.
Starting with the PCV Valve Hose (Long) route the hose from back to front and connect the short end of the hose to the PCV valve. I put blue painter’s tape on the PCV Valve Hose to make identifying the hoses easier. Then, lightly grease the intake manifold connector.
Route the Intake Manifold Hose (short) from back to front and connect the short end of the hose to the intake manifold connector. I found the intake manifold connector was the more difficult one to insert, greasing the connector really helped.
The other end of the hoses should come out next to the oil cap.
Step 4. Install JLT Oil Separator and Bracket
Using a 10mm extended socket and ratchet, remove the ball stud from the intake manifold.
Lightly grease the two connectors on the JLT Oil Separator
Connect the PCV Valve Hose to the “J” side of the Oil Separator.
Connect the Intake Manifold hose to the “T” side of the Oil Separator. Next, mount the Bracket to the JLT Oil Separator using the 2 M4 screws. And finally, using the previously removed ball stud, mount the Bracket onto the Intake Manifold. Do not fully tighten the ball stud.
Step 5. Position JLT Oil Separator
Reinstall the engine cover and position the Oil Separator so the engine cover doesn’t excessively push down on the bracket and oil separator. Once you have the position figured out, check and make sure that the bracket isn’t hitting any hoses, and then tighten down on the ball stud by hand.
The engine cover will rest on the top of the Oil Separator Bracket and according to JLT, this is normal.
Final Thoughts
Oil separators and catch cans in general are one of those modifications that don’t really have a downside. It will keep oil and unspent fuel out of your intake manifold and maintain engine efficiency. An oil separator is definitely a good modification to invest in if you plan on keeping your 4Runner for miles to come.
Check back for an update after 3,000 miles to see how much oil has been accumulated.
UPDATES
@ +1,214 miles: The catch can collected 0.6 oz of oil/fuel.
@ +2,005 miles: The catch can collected 1.1 oz of oil/fuel.
@ +3,278 miles: The catch can collected 1.8 oz of oil/fuel.
*Always recycle used motor oil accordingly.
I installed one a few months back. Didn’t expect it to fill up so fast. After remembering to check after two months it was full to the top. Checked it again after 3 weeks and it was already halfway full. Granted, I do put a lot of miles on.
I have just ordered mine. I do have a couple questions.
1. How often do you check the catch can? 2. What do you do with the oil that is in the catch can when you empty it?
Thanks
Pour it into your crankcase to top off your oil. Is a win/win. Catch the oil in a catch a can, then refill 🙂
I’ve been checking it every 1,000 miles since the instal, I’ll likely change that to every 2,500 miles.
I do my own oil changes so I have a few container that I use to collect used motor oil. Once they are full I’ll take it to my local auto part store or local Household Hazardous Waste Disposal Site.
Seems like an answer to a problem no one is having.
The PCV system is there to help protect the environment. Using this system defeats that purpose. If you do use this system, please dispose of the waste responsibly.
Preach to China and India. Most Americans are responsible.
Only defeats the purpose of the PCV system if the waste is improperly disposed. You are correct always dispose hazardous waste accordingly.
The PCV system in and of itself is actually wasteful. It also degrades your engine over time. The purpose of the PCV system is to vent harmful vapors and waste materials and gases back into your intake manifold in order to be burned up in the combustion Chambers in a never-ending cycle. This actually increases carbon buildup in the engine and decreases fuel efficiency over time in direct injection engines.
The reason they don’t put catch cans on engines these days is simply because the PCV system was simpler and more cost efficient. However, it causes your engine to have more buildup, faster, and lose fuel efficiency and operating efficiency over time. There are many benefits to putting on a catch can, and no downsides, as long as the oil collected is disposed of accordingly. But you have to understand, it’s far more than oil, it’s also carbon deposits and debris that are created by the combustion process in the engine that are fed back through the PCV system. So it’s more than oil you’re keeping from going back into your engine, and is a good idea overall.
I did a similar thing on an exotic engine and had “mayonnaise” build up on the lines, how are the lines doing on yours in that 3k, and build up on the tubes?
So far at ~2k I have not noticed any build ups in the PCV line.
Thanks for posting, I bought one and can’t wait to install it. I’ve been debating getting one for a while.
Says they wont even ship to a CA address… bummer….
The only downside is that if you live in California this can cause you to fail smog due to tampering with the emissions system. That is the only reason I haven’t installed one on my 4runner
Thanks for the heads up! I always keep the OEM parts I take out and good thing swapping it back in is pretty easy.