Help plz crank case ventilation

[wurlycorner]

Might be worth having a look on Simon's build profile to see how he did his 5th? (it'll work the same)

[ddoubledanny]

Might be worth having a look on Simon's build profile to see how he did his 5th? (it'll work the same)

Good shout mate will read now

[ddoubledanny]

Had a quick look at si's turbo 5th gen and it looks like there is just a breather filter and no catch can pcv setup is still original

[Vtecmec]

Cheers mate the catch can has only been on for 8 weeks most would it still be full or need cleaning ?

I would not have thought that 8 weeks would be long enough to fill up, there should be a plastic pipe gauge on the side so you can check.

[106pete]

Just thinking if you set it up my way you'll be pressurising the can and the breather system from the turbo?

I don't think the way it's set up is wrong but normally you'd have a vacuum drawing air out of the system, I'm not sure how you can do that when on boost?

[NafemanNathan]

The head can vent from either exit, it's just the PCV is there to prevent the plenum loosing air pressure if ever there's a negative pressure in the head. Instead it would draw air in from the intake pipe pre-throttle body so as not to effect throttle response.

To me it simply looks like the catch can is overflowing already. Take the top off and have a look Dan.

[PerformanceAutoworks]

Suprised paw set that up. The catch can should go between the pcv valve and the inlet mani.

Why suprised?
The way this is set up is perfectly acceptable for a "low boost application" which was our brief when we did the work!!
We have many low-mid boost applications (and N/A tunes) running this very same setup which works perfectly.
There are many ways of setting up catch tank systems, each has it's merits and downsides.
I get fed up with people critising work without fully understanding the reasons behind it or without the knowledge to back it up!!

The leaking catch tank has sweet FA to do with how the system is set up...it's down to poor quality sealing of the catch tank joints which should have a gasket in there. Have seen this plenty of times on cheap catch tanks.


A few possible methods for CC Ventilation

1) PCV Interupt - From PCV valve to catch tank - Catch tank back to inlet port on inlet manifold where PCV hose used to run to.
Pros - clean, very rare tank needs emptying.
Cons - Catch tank needs to be perfectly sealed otherwise vacuum leaks will cause running problems. Really isn't worth doing as it doesn't extract much oil from the vapour at all.

2) Single port/vent to atmosphere - As DD's setup - Factory PCV left alone. Left hand cam cover vent to intake of catch tank, outlet vented to atmosphere via breather filter.
Pros - Clean, simple, effective, low(ish) maintainence (with a decent catch tank). Engine still breathes exactly as OEM but under high load will vent oil vapour to catch tank rather than back into inlet.
Cons - High boost applications or extremely high revving/high comp cannot vent enough through single outlet hose. Occasional emptying of tank (mostly of mixed oil/water vapour)

3) PCV Delete - Remove PCV and block off inlet manifold port. Either drill out the PCV to remove the valve itself or fit a union to the cam cover where PCV was fitted. Run both ports from cam cover direct to a breathable catch tank. Both hoses can be linked to enter catch can via one port but this reduces breathing volume so ideally both hoses routed to individual ports on a catch can. A third "vent to atmosphere" port will need to be available on chosen catch can (DD will need to add one to his to do this).
Pros - Best CC ventilation you can get on non modified engine/cam cover. Good for most medium boosted or high comp motors.
Cons - Can cause a slight oily smell, catch can level will need to be checked reasonably regularly (each application will vary).
Big boost builds or extreme NA setups still can vent enough due to bore size of hoses.

4) Custom - Lots of ways of doing this using large bore hoses (-10 min) ranging from venting the actual back of the block, venting from front Balance shaft blanking plug (B/S delete obviously), plus modifying cam cover with -10 unions welded in place and all heading back to custom multiport catch tank.
Some can even have an oil return line to allow drain back to the sump.
Pros - Done right, it is everything a RACE or BIG POWER motor needs.
Cons - Massive overkill for anything else. Costly.

[nucleustylzlude]

Finally a decent reply, I saw this yesterday before leaving work and it warranted a long reply but I was out for the evening. I've spent an age reading and understanding crankcase ventilation. It can get confusing and especially the mass of incorrect information out there.

Thankyou Rich for explaining that in quite possibly the easiest to follow little write-up I've seen.

Back to the original question - Danny you really need to whip the tank cover off and see what's inside and check how that thing is sealed. If as Rich says it's a cheapo with no seal, then invest a little money and buy something better. They're not a lot of money for something half decent. But there is absolutely nothing wrong with the way that's setup.

While your on the subject Rich, mine is a combo of methods 3 and 4 you've posted, maybe a slight overkill at this stage but want it future proofed for more boost one day. Question = I'm venting from the front of the valve cover with custom baffles on the inside - you seen or done any like this? Not seen one in the UK that's all. It's just I'm short for space with the supercharger unit at the back.

[ddoubledanny]

Suprised paw set that up. The catch can should go between the pcv valve and the inlet mani.

Why suprised?
The way this is set up is perfectly acceptable for a "low boost application" which was our brief when we did the work!!
We have many low-mid boost applications (and N/A tunes) running this very same setup which works perfectly.
There are many ways of setting up catch tank systems, each has it's merits and downsides.
I get fed up with people critising work without fully understanding the reasons behind it or without the knowledge to back it up!!

The leaking catch tank has sweet FA to do with how the system is set up...it's down to poor quality sealing of the catch tank joints which should have a gasket in there. Have seen this plenty of times on cheap catch tanks.


A few possible methods for CC Ventilation

1) PCV Interupt - From PCV valve to catch tank - Catch tank back to inlet port on inlet manifold where PCV hose used to run to.
Pros - clean, very rare tank needs emptying.
Cons - Catch tank needs to be perfectly sealed otherwise vacuum leaks will cause running problems. Really isn't worth doing as it doesn't extract much oil from the vapour at all.

2) Single port/vent to atmosphere - As DD's setup - Factory PCV left alone. Left hand cam cover vent to intake of catch tank, outlet vented to atmosphere via breather filter.
Pros - Clean, simple, effective, low(ish) maintainence (with a decent catch tank). Engine still breathes exactly as OEM but under high load will vent oil vapour to catch tank rather than back into inlet.
Cons - High boost applications or extremely high revving/high comp cannot vent enough through single outlet hose. Occasional emptying of tank (mostly of mixed oil/water vapour)

3) PCV Delete - Remove PCV and block off inlet manifold port. Either drill out the PCV to remove the valve itself or fit a union to the cam cover where PCV was fitted. Run both ports from cam cover direct to a breathable catch tank. Both hoses can be linked to enter catch can via one port but this reduces breathing volume so ideally both hoses routed to individual ports on a catch can. A third "vent to atmosphere" port will need to be available on chosen catch can (DD will need to add one to his to do this).
Pros - Best CC ventilation you can get on non modified engine/cam cover. Good for most medium boosted or high comp motors.
Cons - Can cause a slight oily smell, catch can level will need to be checked reasonably regularly (each application will vary).
Big boost builds or extreme NA setups still can vent enough due to bore size of hoses.

4) Custom - Lots of ways of doing this using large bore hoses (-10 min) ranging from venting the actual back of the block, venting from front Balance shaft blanking plug (B/S delete obviously), plus modifying cam cover with -10 unions welded in place and all heading back to custom multiport catch tank.
Some can even have an oil return line to allow drain back to the sump.
Pros - Done right, it is everything a RACE or BIG POWER motor needs.
Cons - Massive overkill for anything else. Costly.

Thanks for the advice mate and just to make sure I weren't criticising you work or the setup bud to be honest I think it might be because its a cheap catch can will have to invest in a decent one anyone know the best one for money

[BMCC]

Put a crankcase filter on the inlet and move the catch can to the right place. Paw put it there as you have no connector on the intake