Homemade Catch Can

[Zuffen]

Remember my line returns before the t/b so vacuum is minimal.

 

[ed_ma61]

my home made catch can, air/oil separator with -ve pressure exhaust extraction (two 2stroke reed valves)

 

[Zuffen]

My can has provision (put there by Ford or Mazda) for reed valves as it came with a couple on the inlet pipe.

I'll look into using them.

 

[SC400TT]

Well guys, I have continued to research this Catch Can issue, and I have come up with what I think is closest to the stock Toyota turbo PCV system. I drew a picture in MS Word, but I was unable to save it to a file I could attach to the forum. If any of you can make a suggestion as to how to do this, please let me know. I can email the document to you and go from there.What I decided to do is to keep the driver side PCV basically stock.

• Replace the stock Driver's side PCV valve with a brand NEW OEM PCV valve and route a braided hose to the block off plate which will be drilled and tapped. An AN fitting will be fitted in the block off plate. The new PCV valve should be very effective at stopping oil from leaking into the intake.
• Route the Passenger side breather hose (New braided hose) to a Catch Can, then route a braided hose from the catch can to the inlet on the underside of the throttle body, and place a second PCV valve or a check valve in that line between the catch can and the throttle body. This would catch any oil and debris in the can and the valve will stop any back flow of pressurized air back into the crankcase when under high boost. This should keep fresh air flowing through the crankcase as in a stock application.

I appreciate any comments on this, or help on the pic.

Thanks,

Ryan

 

[-Nemesis-]

Try taking a screenshot with the document open, then cut out the bit you want in a photo prog, save as jpeg

 

[SC400TT]

I took your advice and used my phone to take a screen shot. So as you can see:

• I will replace the stock Driver's side PCV valve with a brand NEW OEM PCV valve (represented by the red dot on the driver side and this assures there is no leaking), then route a braided hose to the block off plate which will be drilled and tapped. An AN fitting will be fitted in the block off plate. The new PCV valve should be very effective at stopping oil from leaking into the intake.
• You can see the direction of air flow by the arrows I have placed in the black tubes I have noted in the diagram.
• Then I will route the Passenger side breather hose (New braided hose) to a Catch Can mounted where the stock carbon canister was located, then route a braided hose from the catch can to the inlet on the underside of the throttle body, and install a second PCV valve or a check valve in that line between the catch can and the throttle body (represented by the red dot). This would catch any oil and debris in the can and the valve will stop any back flow of pressurized air back into the crankcase when under high boost. This should keep fresh air flowing through the crankcase as in a stock application.

Ryan

 

[XR8tt]

Keep in mind .. With forced induction, the PCV closes when engine is in boost.. So the other venting side should be doubled..
In most cases if PCV works as it should it can be left as it is ..
If the crankcase other venting side is done or overdone it should be right..
Through an oil seperator.. Venting back to aircleaner cover is EPA friendly..
You'll get a deffect if you vent to atmo.. Like race cars...

 

[SC400TT]

Another point to consider here.

• The OEM PCV was never made for a boosted car...Even if replaced with a new one, will it be able to function properly at high boost, or will the PCV leak? If it does, then routing it back to the intake on the driver's side will allow oil into the intake. That would not be good.

Thanks,

Ryan

 

[XR8tt]

Another point to consider here.

• The OEM PCV was never made for a boosted car...Even if replaced with a new one, will it be able to function properly at high boost, or will the PCV leak? If it does, then routing it back to the intake on the driver's side will allow oil into the intake. That would not be good.

Thanks,

Ryan

YES you boost the crankcase pushing oil out seals..
Thats why I fit another one way valve or known PCV from boosted car...
The boosted PCV's are usually made from steel ...
I wouldn't use a plastic one on its own...

 

[scotturnot]

I have just read this entire thread and I think I will follow John's plan for mine. Seems the simple and effective.

 

[scotturnot]

Hey Ryan, thought you'd dropped off the map, bud. Is that beast of yours running yet?

Here's what I plan to do for my breather setup:

1) Run a 3/8" (interior measurement) line from each valve cover to a catch can which will be more an air/oil separator than just a catch can (ie it would have some sort of demister pad in it.)

2) Run a 1/2" minimum line from the catch can to the air intake, probably just after the filter, but definitely where there will be negative pressure, not any positive pressure.

3) The catch can would also have a drain line with petcock where you could drain off the accumulated gunk periodically.

To me, this system would do nearly all that the PCV system tries to do, and do it better. Some would eliminate the 1/2" line from the catch can to the intake, and simply vent the top of the catch can with a little K&N filter, however I don't like smelling crankcase fumes in my garage.

I don't know that the height of a catch can would affect its performance at all.

John,
Just to be 100% clear, You plan on running no PVC with this setup right? I was going with the oil collector Catch can with a K@N on top and no PVC. Sounds like thats what you were doing as well.

 

[MWP]

You need to let fresh air into the crank case.
It should be sucked in one side by the vac on the other side (ie, exactly how it came from the factory).

It stops condensation buildup, and also stops fuel in the blowby (along with other gasses) from polluting your oil.

If you want to minimize the amount of oil entering your intake, then "mycarhasposessedme"'s diagram with the two catch cans is the way to do it (turbo or NA).

 

[scotturnot]

You need to let fresh air into the crank case.
It should be sucked in one side by the vac on the other side (ie, exactly how it came from the factory).

It stops condensation buildup, and also stops fuel in the blowby (along with other gasses) from polluting your oil.

If you want to minimize the amount of oil entering your intake, then "mycarhasposessedme"'s diagram with the two catch cans is the way to do it (turbo or NA).

Do you have a direct link to his diagram? I cant find it.

 

[scotturnot]

Never mind, you meant the one in this thread. Thanks

 

[pwd]

I have been experimenting with a catch can set up to see how it works.

The home made can is divided into two chambers with a perforated mesh insert in the bottom section and stainless steel scouring pads fitted under the divider.

View attachment 9172

View attachment 9173

this is only experimental so it it looks a bit neanderthal.

The 5/8 hose from the top goes to the RHS rocker cover.
The 5/8 hose from lower down goes to the intake before the throttle body.
PCV goes to the top of the can,
And the other hose at the bottom is vacuum.

Now even though this was all done about Oct last year, with all the electrical issues I had with the car it hasnt been going till early this year when I pulled the motor and fitted a replacement loom, it is still going which is a bonus, an annoying problem sorted out.

Now I need help with this catch can system that is fitted because I am pressurizing the crank and have blown the rear main seal and is also leaking from the front seal, I was hoping it was plumbed up correctly, and if it is then something else has gone wrong.

So I went and brought another motor, one with a lot less miles on it than mine, I dont want to fit it and do the same thing to it if my plumbing is no good, so any help, ideas suggestions would be appreciated.

 

[Zuffen]

The top hose should go to the intake and the lower come from the cam cover.

 

[cribbj]

I have been experimenting with a catch can set up to see how it works.

this is only experimental so it it looks a bit neanderthal.

The 5/8 hose from the top goes to the RHS rocker cover.
The 5/8 hose from lower down goes to the intake before the throttle body.
PCV goes to the top of the can,
And the other hose at the bottom is vacuum.

Now I need help with this catch can system that is fitted because I am pressurizing the crank and have blown the rear main seal and is also leaking from the front seal, I was hoping it was plumbed up correctly, and if it is then something else has gone wrong.

I think your problem is that bottom line - your source of vacuum. You didn't state where that's coming from, or what it's purpose is.

If that line comes straight off the intake manifold, then it's under positive pressure whenever you're on boost, and it's pressurising the crankcase via the line going to your RHS cam cover (and possibly also through the PCV system if you happen to have turned the PCV valve around the wrong way.)

It's too late now, but it would have been interesting to have had a pressure sensor in your catch can. I'd bet that every time you boosted the motor, you had positive pressure in that can, which is a no-no.

 

[pwd]

The top hose should go to the intake and the lower come from the cam cover.

Thanks Rod but I am pretty sure I have that right, pre throttle body, sucking any fumes into the can and trapping any residue.

 

[pwd]

I think your problem is that bottom line - your source of vacuum. You didn't state where that's coming from, or what it's purpose is.

If that line comes straight off the intake manifold, then it's under positive pressure whenever you're on boost, and it's pressurising the crankcase via the line going to your RHS cam cover (and possibly also through the PCV system if you happen to have turned the PCV valve around the wrong way.)

It's too late now, but it would have been interesting to have had a pressure sensor in your catch can. I'd bet that every time you boosted the motor, you had positive pressure in that can, which is a no-no.

John, the vacuum source is from the intake before the supercharger, and the PCV valve is in the right way.

 

[cribbj]

Gotcha; little chance of that vacuum source seeing any boost ;-) So there's no potential source of boost that could get into your catch can or your valve covers?

Then the crankcase pressure either isn't getting out (PCV not working, hoses too small or too long), or there's too much pressure being generated in the crankcase (blowby).

Have you run a leakdown test to see how the rings are sealing?