Oil Catch Can For Euro 6 Engines

[Therealredford]

The dirty air comes in one and through a wire gauze filter in the centre. Oily residue collects in the bottom and clean(er) air goes back into the intake. I just run a pipe down from the bottom connection to a wheel arch and put an in-line tap on the end. I just drain it whenever I think about it. No smeg goes back....definitely a bad idea!

Have you done this?

 

[Therealredford]

How did you fit it, just cut the pipe and connect each end? Does the drain pipe not get blocked up?

 

[Bundy88]

How did you fit it, just cut the pipe and connect each end? Does the drain pipe not get blocked up?

Not done on a T6 as it’s new and may have warranty implications…
Have done it on Landy…I used new pipes as they had to be longer to reach it. The drain pipe I stuck a plumbing inline valve on it so it’s easy to open and stays closed to hold the crap in until you’re ready to drain it off.

 

[Loz]

I had a look at the pipe today a was thinking of taking to a catch can and just vent through a small filter and then block the rest of the pipe down to the inlet. I don’t see the need to send it back in…

 

[Bundy88]

Some engines are designed to have a closed breather system to maintain a certain pressure, so may not be ideal

 

[Loz]

Some engines are designed to have a closed breather system to maintain a certain pressure, so may not be ideal

It can’t be under pressure if it’s connected to the turbo inlet as that is in a vacuum..

 

[DXX]

Generally from what I’ve seen in most auto engines there is a rubber diaphragm that acts as a pressure control. There will be a slight positive pressure in the crankcase and a vacuum in the induction prior to the turbocharger.

 

[Fluff34567]

I had a look at the pipe today a was thinking of taking to a catch can and just vent through a small filter and then block the rest of the pipe down to the inlet. I don’t see the need to send it back in…

Loz,

Can you describe where the pipe is, or have a pic available - i had a look and couldn't see it, i also have the 204 DSG.

As im in there doing the EGR and charge cooler it would be a good time to try fit a catch can.

 

[Fluff34567]

ref the comments about catch cans with filters - personally I wouldn't fit one with a filter as that can lead to increased crank case pressure and leaking seals, inc the main seal

 

[Loz]

ref the comments about catch cans with filters - personally I wouldn't fit one with a filter as that can lead to increased crank case pressure and leaking seals, inc the main seal

Please explain

 

[Loz]

Loz,

Can you describe where the pipe is, or have a pic available - i had a look and couldn't see it, i also have the 204 DSG.

As im in there doing the EGR and charge cooler it would be a good time to try fit a catch can.

 

[DXX]

ref the comments about catch cans with filters - personally I wouldn't fit one with a filter as that can lead to increased crank case pressure and leaking seals, inc the main seal

I agree that there is a risk if not sized correctly. The pressure only increase if flow is restricted.
Take care with the bore of fittings and hoses to ensure that they are not smaller than the OEM system, avoiding tight bends. There will be some frictional loss in the system but given the short distance required it will be minimal.
In my experience a filter element in the trap is not required, a simple baffle such as a piece of copper gauze will suffice.

 

[Loz]

This is sort of thing I like the look of.


Just bring in the breather from the cam cover and block the down pipe to the turbo inlet.
I could fit a low pressure gauge to the outlet pipe so I can see if it is gaining any pressure.

 

[DXX]

This is sort of thing I like the look of.
View attachment 179071

Just bring in the breather from the cam cover and block the down pipe to the turbo inlet.
I could fit a low pressure gauge to the outlet pipe so I can see if it is gaining any pressure.

If you keep the filter there won’t be an increase in pressure but it may pull air in depending on the vacuum on the inlet. If additional air were admitted it’s after the MAF sensor so it could cause issues.
Fitting a gauge is fine but you’d need to add a long gauge line to be able to read it in the cab under heavy engine load, maybe as a temporary measure to check. Easy enough and cheap to do.
It would be worth measuring the vent system pressure on the OEM system prior to mod’ to see if there are any variation after installing the trap.

 

[Fluff34567]

Please explain

I have seen many cases in the 4wd world where a catch can has an internal filter, it gets clogged then increases the crankcase pressure .

 

[Loz]

If you keep the filter there won’t be an increase in pressure but it may pull air in depending on the vacuum on the inlet. If additional air were admitted it’s after the MAF sensor so it could cause issues.

it shouldn’t suck anything in if I seal off the lower pipe.

 

[DXX]

it shouldn’t such anything in if I seal off the lower pipe.

I‘m sure that small filter is not designed to cope with a no through flow situation. I think you would end up will an oily mess inside the engine compartment if used that way and probably excessive crankcase back pressure / reduced flow.
The flow rate will be determined by the differential pressure. Inlet pressure will be less than atmospheric so the flow rate will be less and back pressure higher.
The standard through flow method as it was designed to be used will remove almost all oil carry over, it will never take out 100% but it doesn’t need to.

 

[Fluff34567]

View attachment 179059

Cheers, has a look today and as I'm LHD it's easy to get my arm down the back, only concern is its a hard plastic pipe so need see how flexible it is .

 

[Fluff34567]

The catch can arrived yesterday, its a provent 200 copy. Stainless filter but with a pressure and vacuum relief valve. Quality wise the body and cap is decent but the pipe fittings are thin, best to reinforce them from inside with a bit of plastic tube.

Only place I can see where to fit it is on the engine cover as its big!

 

[Therealredford]

Are you going to replace the breather pipe with new pipes passing through the catch tank and then a drain pipe somewhere?