can I see oil vent catch cans

[911pcars]

Crankcase blowby exits the engine at relatively high velocity. Routing this into the oil tank allows most of the liquid oil to separate from pressurized gases/air. The oil tank provides an area that allows the blowby/oil mist flow to decrease so a smaller tank can further separate liquid from vapor.

Another plus 1 to not allow condensed H2o, raw fuel, other liquids, etc. to drain/return to the crankcase.

Sherwood

[pmax]

Originally Posted by 911pcars

Crankcase blowby exits the engine at a retatively high velocity. Routing this into the oil tank allows most of the liquid oil to separate from pressurized gases/air. The oil tank provides an area that allows the blowby/oil mist flow to decrease so a smaller tank can further separate liquid from vapor.

From that, I gather the typical catch can is too small if connected to the breather hose directly and the oil loss would be excessive if the blowby is not routed back to the oil tank.

Another plus 1 to not allow condensed H2o, raw fuel, other liquids, etc. to drain/return to the crankcase.

Sherwood

That's the rationale for my previous question i.e. given the blowby oil is contaminated stuff anyway, why not filter first before dumping it back into the oil tank to be recirculated if the oil loss is acceptable.

[chrisbalich]

Originally Posted by pmax

That's the rationale for my previous question i.e. given the blowby oil is contaminated stuff anyway, why not filter first before dumping it back into the oil tank to be recirculated if the oil loss is acceptable.

the fuel and water will be vaporized and should push right back out of the tank into the can whereas the oil will be droplets and fall into the tank as soon as the velocity of the air/oil/water/fuel mixture starts to slow down or cool off.

[KTL]

I'll add that the volume of oil discharged by the crankcase breather can be a major amount of oil that no catch can is able to hold. It's so much oil that it must be returned to the tank. It's also very advisable that the hose from the crankcase breather is humped upward to use gravity to limit the amount of oil that the engine pukes out. Basically at lower rpms the oil can climb up the hose and then slide back back to the crankcase. But at sustained high rpms that oil will keep coming and go all the way to the tank.

In racecars that have a forward mounted tank in the trunk's smuggler's box, the crankcase breather hose is typically routed along the roof line (usually strapped to the roll cage tubing) and that helps limit the amount of oil discharge. Even with the high routing, it still spits a bunch of oil into the tank. I've heard racers that use the clear fiber-reinforced hose say they're shocked how much oil they can see going thru that hose.

[theenico]

Originally Posted by juanbenae

thats closer to 16 AN ? is a single "AN" 1/16"?

AN sizing is 16ths of inch I.D.

-3 = 3/16"
-4 = 4/16" (1/4)
-6 = 6/16" (3/8)
-8 = 8/16" (1/2)
-10 = 10/16" (5/8)
-12 = 12/16" (3/4)
-16 = 16/16" (1)
-20 = 20/16" (1 1/4)

[theenico]

Originally Posted by KTL

In racecars that have a forward mounted tank in the trunk's smuggler's box, the crankcase breather hose is typically routed along the roof line (usually strapped to the roll cage tubing) and that helps limit the amount of oil discharge. Even with the high routing, it still spits a bunch of oil into the tank. I've heard racers that use the clear fiber-reinforced hose say they're shocked how much oil they can see going thru that hose.

This gave me a good chuckle. Back in the late 90s I worked at Cox Motorsports. We did this setup in one of the customer's cars and it messed with his peripheral vision enough that we changed out the clear tubing for black.

[alpenstrasse]

For those of you with Moroso catch cans, are they serviceable? Product description states " internal baffling with mesh media for air-oil separation."
Can the mesh media be cleaned out to make sure they don't clog?

I just have a filter attached to a hose extension from fill neck currently. I get a modest drip here or there so don't realy _need_ a catch can. Just want to make sure that I don't create a problem I don't have by adding a catch can.

Thx.

[80TargaSC]

Hi all,
Can I use a catch can for CIS system?

Thanks,
Khuong

[PeteKz]

Yes, but why would you want to?

If you have the early CIS where the breather hose goes into the right side of the air box, then no changes necessary. If you have later CIS, where the breather hose goes into the intake boot, then you need to plug the hole in the intake boot.

[80TargaSC]

Originally Posted by PeteKz

Yes, but why would you want to?

If you have the early CIS where the breather hose goes into the right side of the air box, then no changes necessary. If you have later CIS, where the breather hose goes into the intake boot, then you need to plug the hole in the intake boot.

Thank you!