Oil Catch Can/spew Tank

[SimonR32]

woops, just realised u cant see the k&n in that picture... its on the other side of the battery to the entry pipe

[Mr GTR-32]

Im with Moodles then if its good enough for Mines,autech and Nismo to sell a product it must be ok, ive run this for 1.5yrs now dont seem to have any dramas on a new fresh engine since, my oil still looks the same as always even before i had it, the oil separator smells of oil only when i remove it for regular maintenence checks, nothing unusual of the colour just good old synthetic oil so i guess a different option for a different purpose but does not mean is so inferior due to its different design usage.

If any one can give good theoretical evidence against it please have a say as so far there is nothing to state otherwise.

[PIOTREK]

anyone got a simular picture for just and rb25 i have the same issue and i just wanna chuck a breather on for track day! so the defect is not a worry unless i'm unlucky and get caught on the way there lol

[PIOTREK]

sorry to hi-jack can someone lable my photo too where the breather should sit

link is here

http://www.skylinesaustralia.com/forums/Pr...on-t272977.html

[jonn]

You recirc it back into the intake so it'll get burnt up for emissions compliance stuff, just like stock does, or you just vent it to atmosphere and it doesn't gum up your intercooler piping. DO NOT DUMP THAT BACK INTO YOUR SUMP.

Please, somebody try to argue with me and say putting what comes out of your blow by catch can back into your oil sump is a good idea. I need some good entertainment.

It's a good idea. Why isn't it?

[Cjmartz2k]

Im with Moodles then if its good enough for Mines,autech and Nismo to sell a product it must be ok, ive run this for 1.5yrs now dont seem to have any dramas on a new fresh engine since, my oil still looks the same as always even before i had it, the oil separator smells of oil only when i remove it for regular maintenence checks, nothing unusual of the colour just good old synthetic oil so i guess a different option for a different purpose but does not mean is so inferior due to its different design usage.

If any one can give good theoretical evidence against it please have a say as so far there is nothing to state otherwise.

They sell their product because you buy their product. Simple as that. How many cranks have you seen that have actaully spun around the small crank collar? How many motors have you actaully seen that have grenaded themselves due to all the oil being stuck in the head? It's amazing how many problems that "must be fixed!!" pop up right after Tomei of HKS or somebody makes a "fix" for them. Great marketing on their part I must say.

What is blow by? If air/vapor from the combustion chamber that gets blown past the rings and into the crank case. What's in that vapor? Well besides some carbon and other general nastyness you wouldln't want in your oil, there is unburnt FUEL. What happens when you mix oil and gasoline? The oil thins out and stops lubricating. If you have very little blow by, your not going to be getting a lot of stuff in the can, and you wouldn't need to add oil a lot, nor would a lot be going back into the sump, so it's pointless at best in the case of little to no blow bye. If you have a LOT of blow bye, your going to need to add oil more often, but also your going to have a whole bunch of nastyness from the combustion chamber getting condensed out of the vapor, and put back into the sump, making your oil even more dirty than it already gets due to the large amount of blow bye your getting. All of that contamination for what? You saving yourself the convienience of not having to check your oil as often? That's rediculous.

My motor was in good shape about a year ago. Little to no blow by. I would have just a little oily residue in my catch can between oil changes. It was thin and reaked of fuel. I wouldn't have poored that into my oil cap to save my life. Now I have a lot of blow bye from a cracked head (don't ask). I have so much blow by I don't even run a catch can anymore. I just aim the pipe down under the car (please no environmentalist speaches). When it was still going into the can, I could almost fill it up over the course of time between oil changes. Again, black as tar, with the consistency of thick black gasoline. Poor all that into my oil cap? No thanks. I'll poor nice clean oil in thank you very much.

Besides, checking my oil when I fill it up with fuel is a good excuse to show off the big single to everybody at the gas station Also, why do you think not one car comes with the plumbing routing blow by back into the sump from the factory?

In summary.................

(1) You are sacrificing your engine oil's vital ability to lubricate in order to save yourself the trouble of opening your hood as often.

(2) They sell it because you buy it.

Any more questions?

[PIOTREK]

can someone confirm if i wanna put a little breather on, all i have to do is attach it to the blue drawn on pipe? (blue pic)

Edited June 5, 2009 by P1OTR

[jonn]

They sell their product because you buy their product. Simple as that. How many cranks have you seen that have actaully spun around the small crank collar? How many motors have you actaully seen that have grenaded themselves due to all the oil being stuck in the head? It's amazing how many problems that "must be fixed!!" pop up right after Tomei of HKS or somebody makes a "fix" for them. Great marketing on their part I must say.

Three motors due to oil starvation and it's a case of cracking the oil pump where the collar contacts, not spinning on the crank (and there's shed loads of those!). That's the ones I know of. Ask a few on here and there will be plenty more.

Edited June 5, 2009 by jonn

[Beer Baron]

Chris, the thing is systems like the nismo one are still plumbed to the intake. so they operate under vacuum. what the do is seperate the nasty vapour with the unburnt fuel gas in it from the oil. they scrub the oil. the oil drains out the bottom of the tank, all the vapour and unburnt fuel etc gets sucked into the intake and is burnt in the combustion process. in my eyes it's not ideal but it's not exactly a death sentence for an engine to run that type of set-up either.

[__PhaseShiftDown]

can someone confirm if i wanna put a little breather on, all i have to do is attach it to the blue drawn on pipe? (blue pic)

If you are want to vent to the atomosphere. You put the breather (air filter) onto the other inlet on the oil catch can.

So if you have 2 inlet on your catch can, one inlet goes to the engine, then attach a filter on the other inlet.

If you have a rb25. Check the thread below and it should answer your question.

http://www.skylinesaustralia.com/forums/Ca...h+can&st=20

Edited June 5, 2009 by __PhaseShiftDown

[__PhaseShiftDown]

woops, just realised u cant see the k&n in that picture... its on the other side of the battery to the entry pipe

I have exactly the same can. What size K&N filter did you put on there? Got the part number? Thanks.

[Cjmartz2k]

Chris, the thing is systems like the nismo one are still plumbed to the intake. so they operate under vacuum. what the do is seperate the nasty vapour with the unburnt fuel gas in it from the oil. they scrub the oil. the oil drains out the bottom of the tank, all the vapour and unburnt fuel etc gets sucked into the intake and is burnt in the combustion process. in my eyes it's not ideal but it's not exactly a death sentence for an engine to run that type of set-up either.

Interesting, didn't know the nismo one did that. I still, as you mentioned, don't think it's ideal to put it back in the sump. I wouldn't do it on mine. The little extra time it takes to check the oil level during a fueling is more than worth the peace of mind I get knowing my oil is as clean as it can be. People spend all kinds of money on expensive oil for as much protection for their engine as possible. Why skimp on keeping a bottle to top it off every once in a while in the trunk (boot)

[djr81]

Interesting, didn't know the nismo one did that. I still, as you mentioned, don't think it's ideal to put it back in the sump. I wouldn't do it on mine. The little extra time it takes to check the oil level during a fueling is more than worth the peace of mind I get knowing my oil is as clean as it can be. People spend all kinds of money on expensive oil for as much protection for their engine as possible. Why skimp on keeping a bottle to top it off every once in a while in the trunk (boot)

Pardon my ignorance but how is the oil from the head of the motor going to have any more/less fuel contamination than that in the sump?

Additionally removing the PCV from the motor is one of the best ways of increasing the amount of oil going into your catch can. That, combined with the illegality of doing so makes me question why people would ever want to. CAMS don't much like the practice either - they insist a large catch can volumes in the absence of a PCV.

For my 10 cents worth a better arrangement is to retain the functionality of the PCV & install either an oil / air seperator (eg a Nismo unit), fix the problem at source (eg Mines cam cover baffles) & or plumb in a decent catch can (ie with a capacity bigger than a can of coke).

[SimonR32]

Pardon my ignorance but how is the oil from the head of the motor going to have any more/less fuel contamination than that in the sump?

Additionally removing the PCV from the motor is one of the best ways of increasing the amount of oil going into your catch can. That, combined with the illegality of doing so makes me question why people would ever want to. CAMS don't much like the practice either - they insist a large catch can volumes in the absence of a PCV.

For my 10 cents worth a better arrangement is to retain the functionality of the PCV & install either an oil / air seperator (eg a Nismo unit), fix the problem at source (eg Mines cam cover baffles) & or plumb in a decent catch can (ie with a capacity bigger than a can of coke).

your pcv valve pulls air from you cam covers to your intake manifold under vaccum... this air is filled with oil

this oil in the air lowers the octane of the fuel and can cause pinging = motor go bang

id rather have oil go in my catch can that into my combustion chamber

[SimonR32]

I have exactly the same can. What size K&N filter did you put on there? Got the part number? Thanks.

sorry mate, it was on my old gtr... i just went down to the local K&N distributor and found a small one that was the right size

[djr81]

your pcv valve pulls air from you cam covers to your intake manifold under vaccum... this air is filled with oil

this oil in the air lowers the octane of the fuel and can cause pinging = motor go bang

id rather have oil go in my catch can that into my combustion chamber

Yes it does. But it can only do so when the manifold is under vacuum, ie off throttle. The likelihood of a lower octane air fuel mixture (which is the effect oil has) in that circumstance causing engine damaging pinging is, IMHO, nil.

This is very different from the oil that goes off the lower side breather which goes through the intercooler & can cause damage to your motor. It is this oil that also pukes out the bovs & stinks up the turbos.

The advantage of retaining a pcv is as you said - it lowers the pressure in the sump. This, in turn, means less windage & less propensity to froth the oil.