Catch can question

[chrisf8657]

I know this may be a stupid question, but I can't find an answer.
Should the filtering material (brillo like) be on the Intake (PCV in) side or the outflow back to the manifold?

Thanks guys

 

[krismoriah72]

The manifold is the intake...its vacuum. Basically catch cans prevent oil droplets from entering the combustion chamber or intake. IMHO if your blow by is that bad a catch can is the least of your problems.

As a side note if you are trying to build one yourself.. its cheaper just to buy one.. less than $20

https://www.amazon.com/Godspeed-Universal-Racing-Catch-Reservoir/dp/B00400XFQ2

 

[chrisf8657]

Yes I know what a catch can does. it has nothing to do for me with serious ring blow by as a problem, it has to do with the PCV, GDI and lack of washdown on the valves and preventing problems further on with coking on a brand new Hemi engine.

I'm not building one, I'm trying to figure out which connection goes to which. The manufacturer didn't specify - is the side with the filter material the inlet or the outlet?

 

[SubieRubyRoo]

I'd put it on the side coming from the VC, so the inlet. The idea is the oil mist will collect on the material and fall out of suspension.

 

[chrisf8657]

Thanks SubieRubyDoo, much appreciated!

 

[thastinger]

Put it between the valve cover and the inlet to the manifold

 

[LeakySeals]

Cherry pick my response, hopefully you can find something helpful. I researched cans and plan on using one on the 03 Maxima which sucks oil into the intake real bad. eBay is full of them. Some with larger capacity, some with a tiny external air filter so you can block it off entirely. Some are oil catch cans, some are air oil separators. Some do both sides of the PCV circuit. The filter/screen/baffle will be before the inlet to the intake manifold. Just as an air filter would be. So if you use an internal filler, you want one with ports at different levels. If you buy one with ports at the same level, like in the cap, you need a baffle (what BMW uses). From what I read they plastic ones leak like crazy, so keep in mind there could be issues with idle, vacuum CELs, etc.

Some info.
https://www.youtube.com/watch?time_continue=5&v=PWz6vCnJ4CA
https://www.youtube.com/watch?v=pA3YfMgofrE
Examples.
https://www.ebay.com/itm/Oil-Catch-...-Blcak-/273509098893?_trksid=p5731.m3795
https://www.ebay.com/itm/Baffled-Aluminum-Engine-Oil-Catch-Can-Reservoir-Tank-Dual-Cylinder-2-Port-Kit/153276977715?epid=21026410784&hash=item23b0051233:g:b4cAAOSw2~Nb-ry6:rk:32f:0
https://www.ebay.com/itm/Universal-3-Port-Oil-Catch-Can-Tank-Reservoir-Air-Oil-Separator-Racing-Baffled/273509100876?epid=28024743994&hash=item3fae69ad4c:g:JmQAAOSwHexcGvRi:rk:11f:0
https://www.ebay.com/itm/Oil-Catch-Fit-For-BMW-N54-335i-535i-USPS-Billet-Aluminum-Can-Tank-Bottle-Baffled/233071470483?_trkparms=aid%3D444000%26algo%3DSOI.DEFAULT%26ao%3D1%26asc%3D55165%26meid%3Dc8f45bc1bc5640a4b30b2205cf6c19f9%26pid%3D100752%26rk%3D1%26rkt%3D3%26sd%3D232959808517%26itm%3D233071470483&_trksid=p2047675.c100752.m1982

 

[si1491]

If you get a chance, take a look at this site and watch the video: there are also links to his blog post where he has pictures of the design/construction process for one of his CCs

http://www.saikoumichi.com/internal_baffle_design.html

 

[Linctex]

Originally Posted by LeakySeals

https://www.ebay.com/itm/Oil-Catch-...nder-Aluminum-Engine-Blcak-/273509098893

?_trksid=p5731.m3795

https://www.ebay.com/itm/Baffled-Al...nk-Dual-Cylinder-2-Port-Kit/153276977715

?epid=21026410784&hash=item23b0051233:g:b4cAAOSw2~Nb-ry6:rk:32f:0

https://www.ebay.com/itm/Universal-...il-Separator-Racing-Baffled/273509100876

?epid=28024743994&hash=item3fae69ad4c:g:JmQAAOSwHexcGvRi:rk:11f:0

https://www.ebay.com/itm/Oil-Catch-...num-Can-Tank-Bottle-Baffled/233071470483

?_trkparms=aid%3D444000%26algo%3DSOI.DEFAULT%26ao%3D1%26asc%3D55165%26meid%3Dc8f45bc1bc5640a4b30b2205cf6c19f9%26pid%3D100752%26rk%3D1%26rkt%3D3%26sd%3D232959808517%26itm%3D233071470483&_trksid=p2047675.c100752.m1982


When you post eBay blinks, delete the ? and everything that comes after it

 

[Rat407]

Catch cans are all the rage in the GM LS world. Especially with the new DI engines. In Camaro's, Corvettes and the GM trucks. Go to any forum and you will find that the Catch Can thread is the about the largest one on there. So many arguments for and not against but just not needed.

 

[badtlc]

Originally Posted by chrisf8657
Yes I know what a catch can does. it has nothing to do for me with serious ring blow by as a problem, it has to do with the PCV, GDI and lack of washdown on the valves and preventing problems further on with coking on a brand new Hemi engine.

I'm not building one, I'm trying to figure out which connection goes to which. The manufacturer didn't specify - is the side with the filter material the inlet or the outlet?


A catch can will catch goop for sure, but it will not prevent DI intake deposits. This has been shown to not prevent deposits all over the mini and BMW forums about a decade ago. The fine vapors still get through and still deposit on intake valves. Don't waste the time or money.

Catch cans are to get the most out of a high performance engine. They aren't for engine longevity.

 

[ZeeOSix]

Originally Posted by chrisf8657
I know this may be a stupid question, but I can't find an answer.
Should the filtering material (brillo like) be on the Intake (PCV in) side or the outflow back to the manifold?

Thanks guys


Are you talking internally or externally to the catch-can? Good catch-cans will have some kind of baffling and/or "Brillo pad" material inside the can to slow down vapor flow to help condense it into oil droplets that fall and collect in the bottom of the can. Doesn't matter where in the can as it will always be between the input and output ports on the can.

 

[Slick17601]

Originally Posted by chrisf8657
Yes I know what a catch can does. it has nothing to do for me with serious ring blow by as a problem, it has to do with the PCV, GDI and lack of washdown on the valves and preventing problems further on with coking on a brand new Hemi engine.

I'm not building one, I'm trying to figure out which connection goes to which. The manufacturer didn't specify - is the side with the filter material the inlet or the outlet?


Hemi engines are still port fuel injection, not direct injection.

 

[StevieC]

I had one on my PFI/DI dual injection setup on my Highlander before I traded it. It caught a bit of oil in the begining but then tapered off so I think it was during the break-in process. I had it the PCV valve line go into the catch can on the filter media side and then return from the can to the intake on the unfiltered side.

My thread is still on here with pictures of my setup and the can etc.
https://bobistheoilguy.com/forums/ubbthreads.php/topics/4891191/1 (My Catch Can thread)
https://www.bobistheoilguy.com/foru...h-can-on-2009-caddy-cts-v-see-it-working (Other related thread I started)

Good luck.