Crankcase Breather VS. Oil Catch Can

BSM 135i · 06-16-2009, 04:39 PM

i just saw on N54Tech.com that BMS is working on a crankcase breather in place of an OCC HERE. They give reasons why the breather would be better but as of right now people are concerned with the breather leaking with oil over time and it's giving the cabin a pretty nasty odor. What are your opinions on it vs. an OCC?

Triple DDD · 06-17-2009, 11:36 AM

bump

ronnyek · 06-17-2009, 11:41 AM

My concerns are that it would seem they solve two different problems. Oil catch can basically intercepts oil in the intake between turbos and throttlebody.... I just dont see how a crankcase breather is going to fix that... I didnt think pcv's were a MAJOR source of oil as much as oil blowby occuring in the turbos themselves.

My135 · 06-17-2009, 12:24 PM

I've checked out Terry's crank case breather design and the biggest flow is they let the oil vapor discharge to the air, and very soon, the engine bay will have oil sludge build up and some of the oil vapor get inside your car and which can smell bad.

I think oil catch can may not condense all oil vapor but it is the best simple design on the market.

BSM 135i · 06-27-2009, 08:04 PM

anyone else wanna chime in on this?

J x K · 09-25-2009, 01:31 AM

occ > breather

akak1997 · 09-25-2009, 02:00 AM

Pros and Cons
OCC
Pros:
no smell.
no environmental or emission issues since every thing is still in a close system.
Engine Bay Bling.

Cons:
maintenance - requires cleaning and emptying oil every now and then creates restrictions
might leak......

Breather (beta Race version, no word on ETA, If the race version works, Terry might make a street version, where it'll be a close system):
Pros: Cheap (beta breather for $20)
Low or No maintenance (might have to clean the filter?)
no restriction
one less thing that will leak
Cons:
smell
might have sludge deposit in engine bay or near the breather
Emission/Environmental issue, venting oil vapor can't be a good thing.

However, Terry did put a filter there to prevent excessive oil vapor getting vented into the air/engine bay, and according to him, because of the placement of the breather, oil collected on the filter will flow back into the crankcase due to gravity. And that's why I sign up for the beta, to see if it actually works.

06-16-2009, 04:39 PM	#1
BSM 135i Colonel 208 Rep 2,229 Posts Drives: 08' BSM E82 Join Date: Dec 2008 Location: Cali iTrader: (23)	Crankcase Breather VS. Oil Catch Can i just saw on N54Tech.com that BMS is working on a crankcase breather in place of an OCC HERE. They give reasons why the breather would be better but as of right now people are concerned with the breather leaking with oil over time and it's giving the cabin a pretty nasty odor. What are your opinions on it vs. an OCC?
	Appreciate 0 Tweet Quote

06-17-2009, 11:36 AM	#2
Triple DDD Enlisted Member 0 Rep 32 Posts Drives: pick 'em up truck Join Date: Apr 2009 Location: P'cola iTrader: (0)	bump
	Appreciate 0 Quote

06-17-2009, 11:41 AM	#3
ronnyek Captain 24 Rep 682 Posts Drives: 2010 Evo MR Touring Join Date: Mar 2008 Location: space iTrader: (1)	My concerns are that it would seem they solve two different problems. Oil catch can basically intercepts oil in the intake between turbos and throttlebody.... I just dont see how a crankcase breather is going to fix that... I didnt think pcv's were a MAJOR source of oil as much as oil blowby occuring in the turbos themselves.
	Appreciate 0 Quote

06-17-2009, 12:24 PM	#4
My135 Lieutenant Colonel 85 Rep 1,609 Posts Drives: Join Date: Mar 2008 iTrader: (0)	I've checked out Terry's crank case breather design and the biggest flow is they let the oil vapor discharge to the air, and very soon, the engine bay will have oil sludge build up and some of the oil vapor get inside your car and which can smell bad. I think oil catch can may not condense all oil vapor but it is the best simple design on the market. __________________ 7/08 135 Coupe, Crimson Red, 6 SP, Sport, Taupe Lette/Aluminum. Performance Mods: JB4 on Map 5, BMS DP Fix V3, Injen polished intake, AR Catless DP, Maddad resonated mid-pipes, aFe exhaust polished tips, ST Suspension Coil Over and Hotchkis front sway bar. Others: BMS OCC, BT Scanner, Mud Flap. Next Mods: AA Front Strut Brace.
	Appreciate 0 Quote

06-27-2009, 08:04 PM	#5
BSM 135i Colonel 208 Rep 2,229 Posts Drives: 08' BSM E82 Join Date: Dec 2008 Location: Cali iTrader: (23)	anyone else wanna chime in on this?
	Appreciate 0 Quote

09-25-2009, 01:31 AM	#6
J x K NF@ E82 28 Rep 264 Posts Drives: E82 Join Date: Sep 2009 Location: FL iTrader: (0)	occ > breather
	Appreciate 0 Quote

09-25-2009, 02:00 AM	#7
akak1997 Major 66 Rep 1,159 Posts Drives: BMW 135 @ 135mph Join Date: Aug 2008 Location: Los Angeles iTrader: (2) Garage List 2008 135i [0.00]	Pros and Cons OCC Pros: no smell. no environmental or emission issues since every thing is still in a close system. Engine Bay Bling. Cons: maintenance - requires cleaning and emptying oil every now and then creates restrictions might leak...... Breather (beta Race version, no word on ETA, If the race version works, Terry might make a street version, where it'll be a close system): Pros: Cheap (beta breather for $20) Low or No maintenance (might have to clean the filter?) no restriction one less thing that will leak Cons: smell might have sludge deposit in engine bay or near the breather Emission/Environmental issue, venting oil vapor can't be a good thing. However, Terry did put a filter there to prevent excessive oil vapor getting vented into the air/engine bay, and according to him, because of the placement of the breather, oil collected on the filter will flow back into the crankcase due to gravity. And that's why I sign up for the beta, to see if it actually works.
	Appreciate 0 Quote