Engine Breather Pipes/System?

**shimmy** · 02-07-2012, 12:42 AM

Can anybody explain to me about this system

1. what does it do?
2. how does it work
3. what would happen if it got blocked or leaked?

**AlexGTT** · 02-07-2012, 12:52 AM

Shim, engine breather system vents any pressure build up and excessive oil vapour from the engine crankcase. As the pistons move up and down and to a certain extent as crankshaft rotates, any piston blow by (there is some in every engine) starts to pressurise the crankcase. A breather system simply vents this pressure.

In earlier years, venting to atmosphere or a catch tank of some sort was all that's required. However, as emissions regs increased this led to slightly more complicated systems to "re-cylce" the pressure into the induction system.

If it blocks there can be excessive pressure build up leading to oil leaks. A leaking system will simply be messy but may also lead to rough running if it's linked to the induction manifold.

Hope that helps.

The Gorilla · 02-07-2012, 11:07 AM

Hi,

Shimmy- there was a thread when
''CantFindOne'' fitted an Oil Catch Tank
which was on the same theme.

As AlexGTT has already posted, its
about Emissions etc

I beleive a Catch Tank is a ''Fail'' in
some European Countries under things
like TUV or CTt.

Regards,

The Gorilla.

**shimmy** · 02-07-2012, 02:23 PM

cheers guys, but what could happen if the system is blocked or leaks?

im particularly thinking about overheating again

shane@mbtech · 02-07-2012, 08:57 PM

Quote:

Originally Posted by shimmy

cheers guys, but what could happen if the system is blocked or leaks?

im particularly thinking about overheating again

It would promote premature engine wear if they were severely blocked, but to get to that stage IMO you would note engine oil leaks first.

PM me everything you have changed on your car.

**AlexGTT** · 06-07-2012, 10:02 PM

Shim, it won't lead to overheating. The excessive pressure build up starts to push pressure/oil past various oil seals in the engine. The main problem would be leaks pass main crankshaft seals, cam seals, etc. It may even blow a breather pipe off/dip stick out, that sort of thing. Also engine pumping would increase leading to small power loss.

The end result would lead to engine wear/damage as Shane said but you'd have to have absolutely no mechanical sympathy if you let it get that bad. Even you'd notice.

**shimmy** · 06-07-2012, 10:09 PM

Quote:

Originally Posted by AlexGTT

...... Even you'd notice.

Don't bet on it

**AlexGTT** · 06-07-2012, 10:11 PM

Quote:

Originally Posted by shimmy

Don't bet on it

Agreed.

02-07-2012, 12:42 AM	#1
shimmy CSL Register Uber-poster! Join Date: Apr 2008 Location: Uk Posts: 14,646 Casino cash: $43909	Engine Breather Pipes/System? Can anybody explain to me about this system 1. what does it do? 2. how does it work 3. what would happen if it got blocked or leaked? __________________ .

02-07-2012, 12:52 AM	#2
AlexGTT CSL Register Uber-poster! Join Date: Apr 2008 Location: Herefordshire Posts: 4,374 Casino cash: $8572	Shim, engine breather system vents any pressure build up and excessive oil vapour from the engine crankcase. As the pistons move up and down and to a certain extent as crankshaft rotates, any piston blow by (there is some in every engine) starts to pressurise the crankcase. A breather system simply vents this pressure. In earlier years, venting to atmosphere or a catch tank of some sort was all that's required. However, as emissions regs increased this led to slightly more complicated systems to "re-cylce" the pressure into the induction system. If it blocks there can be excessive pressure build up leading to oil leaks. A leaking system will simply be messy but may also lead to rough running if it's linked to the induction manifold. Hope that helps. __________________ CSL Register Alcoholics Anonymous Group Leader & Businessman of the Year '93! www.earleyengineering.com Last edited by AlexGTT; 02-07-2012 at 12:54 AM.

02-07-2012, 02:23 PM	#4
shimmy CSL Register Uber-poster! Join Date: Apr 2008 Location: Uk Posts: 14,646 Casino cash: $43909	cheers guys, but what could happen if the system is blocked or leaks? im particularly thinking about overheating again __________________ .

06-07-2012, 10:02 PM	#6
AlexGTT CSL Register Uber-poster! Join Date: Apr 2008 Location: Herefordshire Posts: 4,374 Casino cash: $8572	Shim, it won't lead to overheating. The excessive pressure build up starts to push pressure/oil past various oil seals in the engine. The main problem would be leaks pass main crankshaft seals, cam seals, etc. It may even blow a breather pipe off/dip stick out, that sort of thing. Also engine pumping would increase leading to small power loss. The end result would lead to engine wear/damage as Shane said but you'd have to have absolutely no mechanical sympathy if you let it get that bad. Even you'd notice. __________________ CSL Register Alcoholics Anonymous Group Leader & Businessman of the Year '93! www.earleyengineering.com

02-07-2012, 11:07 AM	#3
The Gorilla S5, Sport Off, DSC M-track Join Date: Apr 2008 Posts: 740 Casino cash: $14401	Hi, Shimmy- there was a thread when ''CantFindOne'' fitted an Oil Catch Tank which was on the same theme. As AlexGTT has already posted, its about Emissions etc I beleive a Catch Tank is a ''Fail'' in some European Countries under things like TUV or CTt. Regards, The Gorilla.