tri_longer 25 Posted July 11, 2006 Greetings, as my first post appreciate if you take it easy. Have a 1.9 GTI with no engine mods which is being used for hill climbs/sprints + driving to and from the events. Out of curiosity I have come across the idea of Oil Catch Tanks, and can understand their purpose. Before posting an enquiry I had a trawl through the SEARCH and read as many of the topics that have been posted on this subject and can now say with some confidence that I have no idea whether to fit one or not, and if so what type. So, if someone could answer a few questions that would be appreciated. 1. Is there any point fitting to a car with standard injection. (surely warm engine fumes will effect performance; reduction in octane level, and warm air etc) 2. If you fit one does it need to have a breather/breathing cap fitted or do you need an enclosed unit? Some like the Mocal have a breathing cap, whereas others appear to have nothing. 3. If fitted would the car pass an MOT, as it is no longer burning the vapour it will not be present emissions. 4. And assuming that all of the above are met, which pipes do I actually fit to the catch tank, and do I need to block/bung anything? Appreciate there is a lot to answer here but I am just learning. Cheers. Chris. Share this post Link to post Share on other sites
engine killer 6 Posted July 12, 2006 the catch tank (actually not a quite catch tank any more) i am using can be described as filler extension. breather is attached to avoid oily fume/vapour all over the engine bay, (Q2). made a hole at the bottom and conneted back to engine so all collected oil will go back to the engine. no hose connected to the intake anymore, this may answer your Q1. a one litre catch tank is required only for some race regulations to avoid spilled oil on the circuit. as long as i know, allowing the (distilled) oil back to engine makes no harm to it at all. Share this post Link to post Share on other sites
Bono 0 Posted July 12, 2006 i've got a home made catch tank, its just a bit of pipe going into a ribena bottle. In the winter it collects loads of water and mayo, i certainly wouldn't want that going into my sump. Share this post Link to post Share on other sites
pugrallye 0 Posted July 12, 2006 a usual purchased catch ttank is designed to be put inline of the original engine breathers, hence some have vents on and some dont. They can all be modified to just accept all the breather tubes though, but you would have to find a way of venting the pressure. Share this post Link to post Share on other sites
engine killer 6 Posted July 12, 2006 please correct me if i am wrong. the original oil filler has two small hoses connected at the top (under the cap), one connected to engine head to collect vapour and the other connected to intake to release vapour. the bottom of it connected back to the block for oil filling. so if water found inside the catcher, does it mean water leak to the oil system? Share this post Link to post Share on other sites
Bono 0 Posted July 12, 2006 yes i think it would. It sounds like the S16 system where the oil filler works as a catch tank. Share this post Link to post Share on other sites
pugrallye 0 Posted July 12, 2006 (edited) so if water found inside the catcher, does it mean water leak to the oil system? No it is condensation, normally more apparent in colder weather, depending upon quantity of course, but would def not use this to diagnose head gasket failure! Edited July 12, 2006 by pugrallye Share this post Link to post Share on other sites
tom_m 0 Posted July 12, 2006 i've got a home made catch tank, its just a bit of pipe going into a ribena bottle.In the winter it collects loads of water and mayo, i certainly wouldn't want that going into my sump. yup, i've got a 2litre vitel bottle for mine. one big pipe from the large outlet of the filler cap to the bottle and block everything else up. works a treat, doesn't collect too much crap which is reasuring, but certainly does its job Share this post Link to post Share on other sites
Bono 0 Posted July 12, 2006 No it is condensation, normally more apparent in colder weather, depending upon quantity of course, but would def not use this to diagnose head gasket failure! Ah, i read that quote as "if theres water there does it leak into the oil system" not did it come from the oil system. Share this post Link to post Share on other sites
TEKNOPUG 3 Posted July 12, 2006 yup, i've got a 2litre vitel bottle for mine. one big pipe from the large outlet of the filler cap to the bottle and block everything else up. works a treat, doesn't collect too much crap which is reasuring, but certainly does its job I have one of these too, albeit with a 1l milk carton. The downside is that it doesn't have a filter fitted to it - so it whiffs a bit - particularly in the cabin if you have the fan on. A proper metal one with a filter would cure this I'd imagine but I can't justify the expense just now. Share this post Link to post Share on other sites