So you think your catch can setup is good enough? Think again!

I recently did a test on the effectiveness of a typical closed loop catch can setup and the result is very interesting. I used a Moroso baffled catch can for the test on a JRSC setup. Turbo setup should be similar.

1. When the engine is cold and driving short trips, the catch can picks up a lot of moisture and condensation from the engine. When I empty the catch can after approx. 300 miles of driving, the catch can contains approx. 3 table spoons of water and a little oily mix!

2. I later added a filter in between the catch can pcv valve and the intake manifold to see how much oil is being trapped in the catch can. after approx. 750 miles of normal driving and boosting 50% of the time, the stage 2 filter has collected a small amount of oil. Imagine this small amount can end up in the intake manifold!

Here is the catch can.
http://www.users.qwest.net/~jo...n.jpg

Here is the stage 2 filter after the catch can.
http://www.users.qwest.net/~jo...r.JPG

I know some people have the type of catch cans that recycle whatever collected in the can back into the crankcase. Personally, I would be worry about having water in my oil!

Modified by JT at 7:54 PM 6/7/2003


Modified by JT at 7:56 PM 6/7/2003

 

Am I missing something here? Wheres the rest of the post

 

Sorry, I accidentaly hit the enter key before the post is finish. See the complete post above.

 

Hey JT,

Great post, lots of good info. I was just wondering where you got that filter at, looks like a fuel filter of some type.

I was also wondering how you have your catch can routed? Is it alright to route from "valve cover fitting ->catch can -> pcv valve ->inline filter ->inlet on turbo compressor" and plug up the top of the intake manifold? I know that under boost the pcv will close and i know that the intake side of the turbo will always have vacuum. Is their a better way to route it?

 

so, would it be correct to have my catch can setup like this: from the valve cover to the catch can inlet and the outlet of the catch to be topped off with a K&N breather filter?

 

Yes, it's simply a fuel filter. It seems to hold up fine without collapsing. However, I do carry a length of pcv hose in my truck just in case it does.

My setup is for a JRSC, so it's a little different than a turbo setup and the placement of the pcv valve might be different due to the different type of engines available, but I will try to provide a little info later.

1. Hollow out the stock pcv valve in the stock oil separator. Reinstall the modified pcv valve.
2. Connect a length of 3/8" pcv hose to the modified pcv valve from step 1. Connect the other end of the hose to the catch can inlet. (side of the can)
3. Install a "Pontiac v8" pcv valve grommet to the top of the Moroso catch can.
4. Install a "Honda" pcv valve to the pcv valve gromment from step 3. Note: it's very important to use the Honda or factory pcv valve. Don't use the Fram Ford pcv valve for this setup. The pcv valve is essentially a "controlled" vacuum leak and it's metered to operate the pcv valve without causing the side effect of a vacuum leak. Many people use the Ford pcv valve simply because it's cheap, readily available and the mating grommet fits the Moroso can. I actually hookup a vacuum gauge to the Moroso can and verify the result with a Ford pcv valve vs. stock pcv valve. The Pontiac v8 grommet also fits the Moroso can and the hole is PERFECT for the stock pcv valve. The HELP! p/n is 42054.
5. Connect a length of 3/8" pcv hose to the pcv valve from step 4.
6. Connect the other end of the hose to a inline fuel filter inlet port. Connect another length of 3/8" hose from the oultet of the inline filter to the "S" tube on the JRSC.
7. Connect a small K&N filter on the valve cover.
8. Done.
http://www.users.qwest.net/~jo...2.jpg

Some additional info...

Ideally, and for best result of a closed pcv setup, the pcv valve should operate all the time. However, we all know if the pcv valve is connected to the intake manifold, it's not very functional during boost.

If you are hooking up a catch can to a turbo setup, connect the hose after the filter from step 6 above to a location that will always have vacuum even during boost. You can verify by placing your finger over the open-end of the pcv valve and check for suction.

Testing:
1. Connect a long length of pcv hose to the source of vacuum.
2. Connect a factory pcv valve to the other end of the hose.
3. Route the pcv hose and the pcv valve inside the car and drive around to see if suction is still present at the open-end of the pcv valve during boost. if not, find another vacuum source that does.

Alternatives to a closed pcv setup:

Keep it simple and run a open setup. No pcv valve, no catch can.

1. Remove the pcv valve and replace it with a larger dia. barb fitting.
2. Connect a larger size hose to the barb fitting.
3. Route the other end of the hose to the ground.
4. Connect another larger size hose to the valve cover.
5. Route the other end of the hose to the ground.
6. Done.

Optional open system with a catch can:

1. Perform step 1 and 2 from above.
2. Route the other end of the hose from the barb fitting to the inlet of the catch can.
3. Perform step 4 from above and route the other end of the hose to the second inlet of the catch can.
4. Install a filter on top of the catch can.
5. Done.

The open system will relief crankcase pressure and prevent oil vapor from entering the intake manifold. However, it doesn't remove contaminates generated from the normal engine combustion process. You will need to change the oil more often.

This is a long post, so please excuse any typo that I made.

 

I've noticed alot of moisture coming from my valve cover breather to my catch can, thats why i dont have it routed back to the IM.

 

this deserves a BUMP...

 

I must thank you for this post. I have been very worried for quite some time now bc of the re-occuring water in my oil, however, now that i have seen this i am extremely relieved. ?.....I know the water occurs in the can but since mine does not flow back into the system, is there any problem. As long as the water forms and stays in the catch can, do i have anything to worry about?