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Catch can oil fumes ??

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Old 18 November 2017, 09:21 AM
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Dave Y
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Default Catch can oil fumes ??

I have a catch can fitted and get oily fumes in car,not all the time .
If it was Castrol R i would love it but Royal Purple isnt the best.
Old 18 November 2017, 09:34 AM
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Hawkeye D
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I get that too, like a mixture of oil and fuel. Not like a smokey smell, fumes. I tend to get the fumes on higher gear pulls, 4th, 5th and 6th.
I put it down to my Mocal catch can having a ventilated cap.


Rather that though than smoke out the exhaust on start up.
Mines a forged 2.5 STi.

It's either that or I do have a slight weep on my drivers side rocker cover.
Here's my can, fits nicely where the secondary air pump was :


https://www.merlinmotorsport.co.uk/p...luminium-m-ct3

What made you get a can fitted?

Last edited by Hawkeye D; 18 November 2017 at 09:38 AM.
Old 18 November 2017, 09:40 AM
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I had a 2.5 forged engine built and fitted.
Old 18 November 2017, 09:46 AM
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Hawkeye D
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It's strange though in my case because where the oil consumption on my build stopped as soon as the can was fitted, my can doesn't actually catch anything.


I was expecting maybe a teaspoon on oil in there after every run, but I get more like just vapour residue.


I wonder now if all I needed to stop the consumption and smoking on start up was a new PCV valve.
Old 18 November 2017, 10:18 AM
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trevsjwood
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Ideally a catch can should have internal baffling and plumbed into the breather pipes running back to the turbo intake, retaining the pcv action. My CC catches very little except at launch starts where it does build up. Certainly no fumes.
Trev
Old 18 November 2017, 10:35 AM
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i will have to investigate more.
Old 18 November 2017, 10:43 AM
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Hawkeye D
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Originally Posted by trevsjwood
Ideally a catch can should have internal baffling and plumbed into the breather pipes running back to the turbo intake, retaining the pcv action. My CC catches very little except at launch starts where it does build up. Certainly no fumes.
Trev


Any pics on how yours is plumbed in Trev?


Where my PCV was is just blocked off with a small piece of Samco hose with a metal bung in it.

Last edited by Hawkeye D; 18 November 2017 at 10:46 AM.
Old 18 November 2017, 02:13 PM
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IainMilford
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I have heard that the ventilated cap does produce fumes, my rcm catch can has a long hose that runs under the car so any fumes escape without entering the cabin
Old 18 November 2017, 02:23 PM
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merlin24
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I vented the catch can to atmosphere via a hose to approx. where the center prop mount is under the wagon to get rid of the occasional fume smell - it's the wife's 2.1 stroker blob wagon and got to keep her happy
Old 18 November 2017, 02:25 PM
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[I]to the right the red pipes T from the head breathers and run to the small inline head filter. The 2 large black pipes, one connected to the crankcase breather which runs to the catch can, the 2nd runs back to the turbo intake pipe. The blue pipe in the foreground is the connection to the turbo inlet from the head CC.



pic of the two catch cans, red pipes- heads, runs back to the turbo inlet. Black catch can which has drain plug at bottom, both have internal gauzing



red pipe/ blue connection pipe to turbo inlet.<br/>The metal head breather pipes had to be replaced with the installation of the Grimmespeed top mount
The head CC which is actually no more than an inline steel mesh filter, I've always found adequate as the heads never produce anything.
Trev
Old 21 November 2017, 12:00 PM
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ScottyPPP
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I'm running an OBP 3 port catch can with the breather on top, VTA.

I've run a bit of hose from the breather down the side of the gearbox with a filter on the end of it. Seems to keep most of the stink away.
Old 21 November 2017, 02:41 PM
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I will try that idea
Old 21 November 2017, 02:52 PM
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Apparently my breather goes back to the inlet ???
Old 21 November 2017, 04:23 PM
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Might help to upload some pics mate. Mine is just vent to air, so 2x head vents and 1x block vent into can, then I've run a hose from the breather on top down the side of the gearbox. My PCV valve is removed and blanked off and nothing returns to my engine.
Old 21 November 2017, 07:47 PM
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I will get some up when I get back home.




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