Doug G

Found this on ebay....got it and for the price, I can't complain. $45 and is baffled too
Hope to run both lines to it and just let it free vent. If that doesn't work, I'll hook up vacuum from somewhere ?

ZONES89RS

iTrader: (25)

Nice, think I might look for one at that price.

Doug G

Act quick

http://www.ebay.com/itm/BLEMISHED-Polished-Aluminum-Breather-Tank-Oil-Catch-Can-Tube-with-1-2-Ports-/251448032754?pt=Motors_Car_Truck_Parts_Accessories&hash=item3a8b787df2

Doug G

Damn... just found some $40 ones .....darnit.

speedtigger

iTrader: (16)

I have always considered the whole point of the catch can was to allow you to run positive crankcase ventilation while keeping the oil out of your intake tract.

Doug G

I know you're old enough to remember that the old cars just vented to atmosphere then the EPA came along and said we needed the PCV.
Not a bad thing with low friction rings and a vacuum pump

I don't have the rings or pump

But, as I said. I'll see how it does as pictured with the 2 lines off the valve covers and maybe add a fitting where the filter is for a vacuum source later if needed ?

My first outing oiled the track due to the internal pressure and blew out a spray of oil from the dipstick tube.
I added just a filter (like the one in the picture) to the oil fill cap for my next outing.....no oil down or smoke trail but did see oil residue in a few spots.
I'm adding this to the system and we'll see if it's gone
Could the internal pressure have been from the rings not seated ? Motor (fresh build) did have less than 100 miles on it with rings gapped for a 150 hit....hell, might not have 100 yet

Pop N Wood

iTrader: (1)

How do vented catch cans work with a PCV system? Seems like intake vacuum would just draw air in through the filter and not the crankcase.

speedtigger

iTrader: (16)

Turns out, that is not what he is after. He just wanted a breather that would not drip oil on his valve covers.

Doug G

Yes.... IF I remove the filter and add a vacuum line then the baffles will still work.

As it sits it would just allow the motor to vent with no vacuum and not build pressure.

Serioussn95

iTrader: (1)

i have this exact catch can. Its very nice and quality built, cannot beat for the price.

newschool72

iTrader: (12)

Im with you Pop. I understand the catch can idea. It more or less, just gives the oil some place to drop out before it feeds back in the intake, but the vented part doesn't compute with me? The vent is a place for fresh air to enter the engine, while the intake vacuum pulls air out, while at part throttle, then doesn't do too much while at WOT, other than maybe be another place for the pressure to vent out of.
Great price though! I guess you could put a plug in the breather hole in the catch can.

Doug G

Yes, only a breather to allow filtered air into motor and any pressure built up (like blow-by) an escape route.

Not a PCV in there is NO vacuum. But does allow the motor to vent, soooo really is a positive crankcase vent....roughly speaking.

Prorac1

iTrader: (4)

I have mine set up with a fitting on the driverside valve cover going to a baffled/vented catch can to atmosphere. I have expiermented with adding another breather on the pass side with no perceptible difference. I don't have any problems with back pressure, etc. I street drove this setup about 3000 miles last year and it worked great.

Also, Ive never had a problem with oil mist from the can vent AT ALL. That's the part that kinda shocked me. Eric L

newschool72

iTrader: (12)

Ive never had an issue with oil mist either, but Im running a PCV. I don't have a catch can, although I think I should. Funny story, some of you might know about my cookie cutter cold air pan . At some point in the construction and testing, I had my filter setup too restrictive AND the seal to my cowl hood is very tight. I did a test run and my car started smoking so bad that I couldn't see behind me at WOT! The only extra air my engine could draw was from the crankcase and it was sucking oil and air from my PCV like a straw! I freed the filter setup, up and it hasn't smoked a bit since. I never would have thought that could happen, but it did. Good thing my test spot isn't long enough to stay in it for very long, or I might have sucked the engine dry, LOL.

fast89stang

iTrader: (2)

I had no issue with pressure escaping before, but now ,with the crankcase evac set up, it works like a charm and It has always picked me up a tenth, with no oil smoke out my exhaust. I didnt even check my ring gap, but I eyeballed them. Maybe with only 70k it was ok. I havent touched mine this winter yet, had lots of plans, but nothing yet.

camarozz383

iTrader: (3)

hey guys, should I use a catch can on my 5.3 carb motor? cant seam to figure out what to do with the ports on my valve covers and valley cover, here's a pic circled in red, cant see the one on the left, but there one on the cover there as well, thanks

Doug G

Couldn't hurt.

My issue was first run at the strip, the dip stick blew out and sprayed oil everywhere.
My first fix was to ad a breather to the oil fill cap. I'm still seeing oil in PCV lines to intake/carb....so I'm adding this can and deleting the lines to the carb/intake, then go from there.

Some guys have no issue and others do.....haven't figured out yet

WE TODD DID

iTrader: (2)

Yes, you're on the right track by getting rid of the pcv. You don't want oil sucking in the intake side of the engine.

baronsmith98

iTrader: (2)

You could maybe try the catch can In between the pcv and carb but plug the filter hole. This should allow the unburnt air/fuel ( mostly just air) to recirculate back to the intake at idle and slow speeds and capture the oil in the can and keep it out of your carb and intake. I have the same catch can and am going to try this.

newschool72

iTrader: (12)

You need the vent filter to allow fresh air into the engine. The catch can is designed to allow the oil droplet to drop out of the crankcase pressure, before it gets to the intake. If air is going out of the engine via the crankcase, fresh air needs a way to come in. 7K rpms turns the crankcase into a violent tornado of oil and air. If you don't suck it out, it will find another way out, and all over your engine, and the track . The LS engines need a catch can because they create a lot of case pressure compared to a lot of other engine styles. Why, I don't know.