Catch Can
- Thread starter Joshkcupra
- Start date
I tried removing mine yesterday and in the process have damaged the screw holes which are made of f**king plastic, which looks like the only way to fix is to buy a whole new plastic head cover! What a stupid fu**ing design
thats not entirely true though if a catch can stops a small amount then thats stopping some of the crap building up on the valves.
i think the issue is people fit a catch can then expect that to do all the work but the truth is the cam cover is still piped up to the turbo which my thinking is that this is still ending up on the valves from this pipe work so the catch can is doing some of the work but without blanking the tubing at the back of the cam cover the valves are still getting scummy.
wmi is active during boost so only cleans when on boost so this leads to build up even on clean valves so your still going to get build up when not on boost.
(My thoughts)
The catch can could be effective if it was catching all from the cam cover but its not because of the exit at the back of the cam cover which still ends up on the valves so loosing the exit at the back of the cover and fitting a catch can will stop the cam cover recycling its own mess which in turn end up on the valves.
personally i think with a breather ran down the back some where.
Im going to be trying something new out soon that people dont seem to be trying which i think might work but it may not that said you dont know until you try.
this is the idea i thought of after seeing the rear pipe having been deleted on intergrated engineering cam cover i like the look of there cam cover just not the price and id like an alternative and below is what ive come up with in terms of not allowing oil into the intake system at all.
catch by cupra,al, on FlickrThe purple line in the middle runs off the back of the cam cover this gets T'eed into the catch can pipe im not sure if its going to the inlet in the pic or not yet but need to look into it a little first.
The blue line on the left is just showing i would run a breather to atmosphere.
The green line on the right im not fully sure of the function of this pipe but if possible will run it into one of the catch can pipes depending on its operation.
I have followed the pipe on the far right but it goes out of sight under the inlet manifold does anyone know what that ones for or its purpose?
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Pipe that runs under the inlet is the main crankcase breather
Can't view the image in work but sounds very interesting. Not really a fan of the idea of removing the rear breather though. The way i understand it, the PCV valve allows strong syphoning under vacuum/idle, but is closed under boost. The rear breather will syphon under boost as there will be a vacuum created in the intake when there is a large airflow created by the turbo. You would want a very large unrestrictive breather if you will be venting to atmosphere only
Can't view the image in work but sounds very interesting. Not really a fan of the idea of removing the rear breather though. The way i understand it, the PCV valve allows strong syphoning under vacuum/idle, but is closed under boost. The rear breather will syphon under boost as there will be a vacuum created in the intake when there is a large airflow created by the turbo. You would want a very large unrestrictive breather if you will be venting to atmosphere only
Thanks for that.
The main reason i want rid of the rear breather or to link it into the catch can is to stop oil accumulating in the ic and making its way up to the inlet and then the valve backs this is my main concern and i believe the reason as to why so many catch cans are not completely preventing oil from ending up on the backs of the valves.
The main reason i want rid of the rear breather or to link it into the catch can is to stop oil accumulating in the ic and making its way up to the inlet and then the valve backs this is my main concern and i believe the reason as to why so many catch cans are not completely preventing oil from ending up on the backs of the valves.
I'm not convinced the rear breather is the issue. Upon fitting my FMIC my original cooler was bone dry, as was the pipework. Inlet flaps were a bit mucky but nothing significant, yet my valves were caked at only 55k miles. I suspect the oil finds its way past the stem seals, and with out a petrol mix flowing over them like you would have in an older engine, or the twin injection you get in the newer TSI, there is nothing to wash it away from the valves.
Haven't tested which way the flow is for the 2 catch can pipes, but I get a build up of Mayo/gunk in the pipe on the right (indicated green) which is caught by my catch can, as my car does a lot of short journeys
Haven't tested which way the flow is for the 2 catch can pipes, but I get a build up of Mayo/gunk in the pipe on the right (indicated green) which is caught by my catch can, as my car does a lot of short journeys
Does your catch can not cause odours in the cabin when you turn your heater on? It's fine if I'm moving, but when stationary I just get a whaft of oil/petrol fill the cabin!
Does anyone know if the PCV system differs on the single charged 1.4 tsi or do they all follow the same principal???
I was really hoping you wouldnt say that i may still pursue with this as i still dont want oil on the comp wheels.
Joshjcupra that catch can could easily have the filter moved on a pipe so you dont get the odours.
Yes, You are right, the smell comes inside, but using air recirculation makes windscreen foggy
Any options to solve it?
To those of you who doubted that wmi wont keep the inlet valves clean, please think again. I have a couple of photos here which show the cleaning effects of wmi. These valves were cleaned manually 2 years ago. Inlet manifold removed today for inspection and for runner flap delete.
Not the clearest of photos but you can see the light shining off the valves.
So there you have it, if you want clean valves, fit a wmi kit!
Not the clearest of photos but you can see the light shining off the valves.
So there you have it, if you want clean valves, fit a wmi kit!
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