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Hey all,

My catch can filters were filthy with crap bubbling out and dripping everywhere, so when I changed the oil I gave them a good clean.

Now that the filters aren't saturated in crap, there is quite a lot of vapour coming out of the filters.

It seems to smell kind of sweet, doesn't smell like exhaust gas or anything like that. I would say the amount lessens or stays the same with revs - it doesn't appear to get any worse.

Here are a couple of videos showing the vapour.

https://photos.app.goo.gl/pnYO6bEGi3dFsCHk1

Keen to know what people think!

 

Cheers,

Edited by Jazzadub

@Dose Pipe Sutututu Don't worn valve steam seals usually cause oil burn in exhaust?

How would it cause excessive vapour from the catch can? Oil leaking in to cylinder and then oil fumes passing rings in to crankcase?

Edited by Jazzadub
  • Haha 1

@Dose Pipe Sutututu Just checked my records and valve stem seals were done when the head was reconditioned about 7300kms ago?

Also, I don't think I am seeing any blue smoke out the exhaust. I think the only smoke out the exhaust is from fuel; when it's running rich for any reason, backfiring etc.

Nope, not that I am aware of. And I frequently check that the coolant system is topped up and bled correctly.

Why do you ask?

... I have to do that because there is a hairline crack in the coolant jacket on the passenger side of the block :(

Really really slow leak, but it's a massive pain because I run Evan's waterless coolant, and that shit's not cheap. Really need to figure out a permanent way to fix that ...

Edited by Jazzadub
coolant, and that shit's not cheap. Really need to figure out a permanent way to fix that ...

 

Remove coolant.

Remove turbo piping.

Cover up turbos or remove them.

Use a multitool to remove paint and dirt. Do this properly!

Use JB-Weld super glue/metal.

Let it dry properly!

Job done

 

  • Thanks 1

Thanks, will have to get that sorted one day.

Anyone got any more ideas regarding the blow by?

Maybe it just needs more time running after the oil change or something?

www.turbofast.com.au/TurbochargerFactsAndMyths.html

This is a source to have absolute faith in.  Probably an issue with overall breather design.  Mechanical baffling in the cam covers, breather hose sizes, catch can internal design and volume, and breather filter size/number.

You see people running two cans in series sometimes, looking to deal with heavy breathing/smoking.

Hose routing/orientation is also a factor to avoid oil vapours condensing and pooling in dipped/low sections.

There is a bit of thought/effort to get this aspect right.

Thanks I will check that link.

It hasn't always done this, so I don't think it is a design issue. It's a RIPS catch can with two feeds from rear of rocker cover, and two drains back in to sump.

There is a 1.2mm oil feed restrictor in the head also.

But in essence you think the amount of vapour could be normal, it's just not being condensed back in to oil correctly?

Or potentially the turbo oil returns have become blocked or restricted?

Edited by Jazzadub
1 hour ago, Jazzadub said:

But in essence you think the amount of vapour could be normal, it's just not being condensed back in to oil correctly?

That would be my line of thinking.

Everyone has an idea, and in Interweb forum land we are all experts.  But all engines breathe.  And the pressure in the sump carries vapours.  Emissions-legal cars have the vapours going into the inlet to be burned, normally shows up with all that caked on oil/grease trail in the inlet.

So it takes a bit of trial and error to configure a catch can setup that doesn't puff smoky vapours.

Just because a catch can has a workshop's name on it, doesn't mean it will work perfectly (even if it's better than many others).

I doubt if the turbo drain has become restricted, but it wouldn't hurt to inspect and consider whether it's sized and routed as well as possible.  All factors can impact results, so have a look.

One thing I found with my 30DET over successive track seasons, is that the engine breathes.  I have implemented a number of modifications to the setup, and this has helped a LOT to get things satisfactory (not a smoky oily mess underbonnet when a run is finished anymore).  But familiarity with the car etc means it's being driven harder/faster, and I wipe a rag around the catch can outlet to clean any haze that's evident.

Thanks. I hope it is just normal breathing as the compression was tested recently.

The amount of vapour only really became noticable when I cleaned the catch can filters.

Do you think I should oil the filters? I have some K&N filter oil. Perhaps that would stop the oil vapour passing the filters and keep it in the catch longer so it can condense?

I might clean them again and give that a try..

I'd say nature will take its course, and they will be well oiled without using the K&N stuff.

I generally give mine a hit with degreaser after a couple of events, reduce the saturation levels (probably a pointer that my system isn't quite right either).  

Ahh cool. I guess I'll see if it lessens over time.

 

Do you think the catch can itself could do with a clean? It doesn't have internal access but I have a lot of ethanol I could soak it in?

Not a fan of catch can air filters. If you have that much stuff coming out on a regular basis you need an in-line air/oil separator or a second catch can - pull the hoses off to see if its coming from the sump or the cam covers...and then route the (last) catch can into the turbo intake.

Just now, KiwiRS4T said:

Not a fan of catch can air filters. If you have that much stuff coming out on a regular basis you need an in-line air/oil separator or a second catch can - pull the hoses off to see if its coming from the sump or the cam covers...and then route the (last) catch can into the turbo intake. Worst case scenario - broken rings.

 

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