Catch can failure?

[Bad-Trol]

Hey guys, I bought a catch can a while back and although it is catching oil, I'm still finding oil build up in my inlet, turbo, and intercooler. I know I'm not overfilling the oil and I'm pretty sure I'm not getting that much over boost (most I get right now is 22psi, but installing Dawes tomorrow)
Any thought?
Cheers.

[megatexture]

what brand catch can you got ?

[nissannewby]

Could be your turbo seals. Im not a fan of these catch cans but you could still get a small amount threw them there will be other here who have experience with these. However it could be turbo related and your getting oil past the seals it wouldnt hurt to check this out also.

[Robo]

Could be your turbo seals. Im not a fan of these catch cans but you could still get a small amount threw them there will be other here who have experience with these. However it could be turbo related and your getting oil past the seals it wouldnt hurt to check this out also.

X2 on the turbo seal issue

[97_gq_lwb]

Easily diagnosed check the line from the catch can to the inlet and if you have oil pre turbo catch can isn't working.
If it is the typical catch can it will need baffling to catch oil otherwise they are useless.
I baffled mine and it worked but i wish i had spent the money on a provent one .

[Bad-Trol]

It's a custom unit from a reliable 4x4 workshop. I replaced my turbo before the can went in so if it has failed, there is something very wrong with my system. I bought the turbo as a new unit from Turbotech who is highly recommended by everybody I spoke to, so I can't see it being a faulty unit.
The catch can guys have sent me a new can at no charge to see if it's the can... Now that's customer service! And yes it is baffled ;) they did say my crank case could be over pressurizing... How does that happen and what can I do to check it?

[my third 256]

did they put the one way valve back in when they did the plumbing

[Bad-Trol]

Interesting... I did the plumbing... Simply removed existing hose with new one and added the can half way along the new hose.
Where is the one way valve?

[nissannewby]

If your crank case is pressurising you have a lot more to worry about than the turbo. Vent the crankcase to atmospher block off the inlet for it on the intake drive it for a few weeks and see if it has changed.

[boots]

Interesting... I did the plumbing... Simply removed existing hose with new one and added the can half way along the new hose.
Where is the one way valve? It is inside the original hose , I just used a joiner and new hose and left the original hose connected to the rocker cover .

[my third 256]

It is inside the original hose , I just used a joiner and new hose and left the original hose connected to the rocker cover .
x2 thats the easyst thing to do orpush it out with a screwdriver
have a look at page 42
http://www.nissanpatrol.com.au/forums/attachment.php?attachmentid=82&d=1277205981

[Bad-Trol]

I can't open that document yet. But what you're saying is I need the valve in there? Does it help create back pressure or just prevent water, dust, and moisture from going into the crank case?
Thanks for the info, this is interesting

[Bad-Trol]

x2 thats the easyst thing to do orpush it out with a screwdriver
have a look at page 42
http://www.nissanpatrol.com.au/forums/attachment.php?attachmentid=82&d=1277205981

Ok, so found that restrictor yesterday in my shed, popped it into the new hose, but what exactly does this thing do? I would have thought that restricting the crank case would be a bad thing?

[Lieney]

My catch-can had an orofice that was causing a slight restriction and increased pressure in my crank-case.
The over-pressurisation of the crank-case caused my turbo seal in the compressor side to leak.
There were other issues aswell, but ultimately, I had to replace my turbo.
In my car I found the best option to make it work was no restriction or valve between the PCV outlet, through the catch-can, and into the inlet after the air cleaner.
Crank case pressure can = worn piston rings, worn bore, possible crack. Not good

[Bad-Trol]

My catch-can had an orofice that was causing a slight restriction and increased pressure in my crank-case.
The over-pressurisation of the crank-case caused my turbo seal in the compressor side to leak.
There were other issues aswell, but ultimately, I had to replace my turbo.
In my car I found the best option to make it work was no restriction or valve between the PCV outlet, through the catch-can, and into the inlet after the air cleaner.
Crank case pressure can = worn piston rings, worn bore, possible crack. Not good

Interesting, why does Nissan put that in there then? How did u test for the pressure? Is that something anyone can do?
Cheers

[my third 256]

My catch-can had an orofice that was causing a slight restriction and increased pressure in my crank-case.
The over-pressurisation of the crank-case caused my turbo seal in the compressor side to leak.
There were other issues aswell, but ultimately, I had to replace my turbo.
In my car I found the best option to make it work was no restriction or valve between the PCV outlet, through the catch-can, and into the inlet after the air cleaner.
Crank case pressure can = worn piston rings, worn bore, possible crack. Not good
what brand catch can mate

[Bad-Trol]

what brand catch can mate

Well, I don't really want to say because they have been a huge help with so many things I've done to my vehicle which is why I bought the can off them. I'll just say its a custom fabrication place and I have read on this forum SINCE buying it, that they are notorious for poor cans; regrettable considering their other items are amazing and the customer service is well above my expectations, they even sent me a free replacement can to see if there was any dramas with the original.

I'm going to do a complete clean this weekend and them drive for awhile, check catch can after a week and see where I stand. If I'm not happy, I'm going to get a Provent and compare notes.

[my third 256]

Well, I don't really want to say because they have been a huge help with so many things I've done to my vehicle which is why I bought the can off them. I'll just say its a custom fabrication place and I have read on this forum SINCE buying it, that they are notorious for poor cans; regrettable considering their other items are amazing and the customer service is well above my expectations, they even sent me a free replacement can to see if there was any dramas with the original.

I'm going to do a complete clean this weekend and them drive for awhile, check catch can after a week and see where I stand. If I'm not happy, I'm going to get a Provent and compare notes.
i put the provent on mine and didnt use the restricter out of old pipe

[Steveo_the_Devo]

i put the provent on mine and didnt use the restricter out of old pipe

Did the same & seems to be working without a problem.

[Bad-Trol]

Did the same & seems to be working without a problem.

Sounds good! How much oil is the can collecting? Is ANY oil going all the way through?

[my third 256]

Sounds good! How much oil is the can collecting? Is ANY oil going all the way through?
about 100ml every 2000k and nothing going through have used clear pipe so i can see

[cairnsGU]

While motor is idleing pull dipstick out and see if pressure is being released from sump. Good indication of blow by and crankcase pressure buildup

Dan

[Drew]

i put the provent on mine and didnt use the restricter out of old pipe
My old hose didn't have one.

[Lieney]

Correct me if I am wrong, but a catch-can re-directs gasses / oily air from the crank-case, caused by excessive 'blow-by'.
The catch-can 'filters' the oily crap out and returns cleaner air to the inlet.
Mine catch-can is home-made, using a sedimenter / water seperator and coarse steel wool as the filter.
The gas travels down the centre through a tube, then turns 180 deg and comes back up through the wool into the inlet.
Since I opened up the ports a little more it was running sweet.
Crank-case blow by test.
Its not a test as such but can give an indication of engine wear. Remove the oil filler cap in the rocker cover after the engine has been warmed up and running.
Any gas pressure pushing out of this opening at idle would effectively be 'blow-by' gasses caused by excessive piston ring wear, out of round bore etc etc.
Combustion of gasses (air & fuel) is forced past the piston on the combustion stroke and up through the galleries and through the PCV, or in this case, out the oil filler.
The more knackered the engine is, the more pressure will be evident.
The tighter seal between the piston and cylinder, the less gas escapes, the more power and less 'blow-by'.


Remove catch-can and plumb as per original set-up.
Clean your inlet, intercooler etc and run it up the road for 5 mins or so.
Come back and pull it down.
Oil in PCV line, before turbo, will be sorted by suitable catch-can.
Oil in turbo, but not where PCV inlet is would mean turbo seal.