MK5 Golf GTI

All Things Mk5 => Mk5 General Area => Topic started by: Pauli on October 18, 2009, 11:06:15 am

Title: What is all this catch can talk?
Post by: Pauli on October 18, 2009, 11:06:15 am
After reading a few posts, i was wondering, what does this catch can do, how why and when is it used? Any help would be appreciated.
Title: Re: What is all this catch can talk?
Post by: RedRobin on October 18, 2009, 11:45:14 am
....

Welcome to the forum, Pauli :drinking:

Rather than repeat loads of detailed info in this thread which duplicates stuff, hit the Search button and type in the words catch tank and various threads will come up in which it's all discussed.

If there was just one thread I'd post you a link here but there are quite a few!

Recently there was a big Group Buy on the BSH version supplied by forum member Dubtek.

I hope this helps,
Robin :happy2:
Title: Re: What is all this catch can talk?
Post by: KRL on October 18, 2009, 11:52:52 am
Engines suffer from something called blowby and VAG cars are especially known for suffering from this.  A good indication of this can be seen from how much oil your car uses.  Blowby occurs during the combustion process when when gases and oil vapor leak through the piston rings. For emission compliance these gases and vapors are recirculted back into the engine through the OEM PCV with the theory being that they will get burnt off again once they go through combustion.  However in reality the dirty oil vapors and gases tend to stick  to your intake valves etc and cause carbon deposits.  Over time these will cause a nasty build up of what can best be described as sludge which can have a negative effect on your engines performance.  Our FSI engines use direct injection which makes them more susceptible to these carbon deposits than port injection engines as they do not have fuel passing over the valves to wash them clean.

A catch can system sends the blowby gases through a catch can which filters out the oil vapors and allows them to collect in the can which then needs to be emptied periodically.  Therefore the can still meets emission standards as these vapors are being contained.  Also the catch can will help prevent the build up of the nasty carbon deposists.

HTH  :happy2:

Title: Re: What is all this catch can talk?
Post by: RedRobin on October 18, 2009, 12:01:17 pm
^^^^
Great post by KRL :notworthy:

Here's an illustration : -

(https://www.mk5golfgti.co.uk/forum/proxy.php?request=http%3A%2F%2Fwww.carbing.co.jp%2Fenglish%2Fproducts%2Fcatch%2Fimage%2Ftheory_oil.gif&hash=59e3c160a905d65a260f86c3f57b142558740927)

And here's one of john_o's legendary threads : - PCV/Intake Valve Clogging.... (http://www.mk5golfgti.co.uk/forum/index.php?topic=7040.0)

:happy2:
Title: Re: What is all this catch can talk?
Post by: DanoGTI on October 18, 2009, 12:08:03 pm
FOr all of us visual learners, FANTASTIC diagram there Robin  :congrats:

Looks like a worthy investment.

I could have sworn I read somewhere that these cans can affect MOT emissions.... or did I dream that!!

It also seems like pretty new technology (VAG-related anyway) - personally I'm not 100% keen on trying it until it's been proven properly..... unless it already is!!! LOL!  :grin:

Kudos, my friend, Kudos  :happy2:

DAn
Title: Re: What is all this catch can talk?
Post by: KRL on October 18, 2009, 12:23:15 pm
I could have sworn I read somewhere that these cans can affect MOT emissions.... or did I dream that!!

If you have a VTA (Vent To Atmosphere) can it will affect emissions however the standard catch can which is contained should not.
Title: Re: What is all this catch can talk?
Post by: RedRobin on October 18, 2009, 12:27:30 pm
^^^^
@ Dan:

According to KRL's post, the vapours are being contained and therefore emission standards are still met. However, this implies that a Race Can version would not pass MOT on emissions. [Ooops! KRL answered in the previous post]

"Visual Learners" - Us designers are simply hardwired into eye-candy!

(https://www.mk5golfgti.co.uk/forum/proxy.php?request=http%3A%2F%2Fdaz.co%2Fmedia%2FRedRobin_05%2FRED_INK%2FKarmann.jpg&hash=a08402ef7208e7674c5a53b848d3fe58f068d1f8)
Title: Re: What is all this catch can talk?
Post by: bacillus on October 18, 2009, 01:39:30 pm
I can confirm that a car with the BSH recirculating catch can setp will pass the MOT emission test. This assumes that the car is working normally and that your CAT is functioning properly.
Title: Re: What is all this catch can talk?
Post by: big al on October 18, 2009, 04:44:58 pm
How easy are these to fit, and how easy to empty?
Am getting tempted by one now.
Title: Re: What is all this catch can talk?
Post by: Pauli on October 18, 2009, 05:22:17 pm
Cheers KRL, answered my question and then some
Title: Re: What is all this catch can talk?
Post by: bacillus on October 18, 2009, 06:59:07 pm
How easy are these to fit, and how easy to empty?
Am getting tempted by one now.

On a scale of 1 to 5 (5 being most difficult) I would rate it as 2 in difficulty.
The can comes with a drain at its bottom for emptying the contents.
Title: Re: What is all this catch can talk?
Post by: big al on October 18, 2009, 09:32:40 pm
How easy are these to fit, and how easy to empty?
Am getting tempted by one now.


On a scale of 1 to 5 (5 being most difficult) I would rate it as 2 in difficulty.
The can comes with a drain at its bottom for emptying the contents.

Sounds good, any plans for another group buy on them, or has everyone already got one?