PCV/Catch can question

[BlitZ]

ok..might be a noob question...

All i know so far:

- used to relieve crank case pressure and in the air/pressure there is oil mist.

Where does crank case pressure come from??
and what is the crank case? is this the head?
If its the head, does that mean you might need a valve job re seat the valves assuming the pressure is coming out of the valve seats?



regards,
daniel

[tinkerbell]

Where does crank case pressure come from?? the pistons moving up and down
and what is the crank case? it is where the crankshaft is. is this the head? no.
If its the head, does that mean you might need a valve job re seat the valves assuming the pressure is coming out of the valve seats? no.

see bold

[tinkerbell]

http://en.wikipedia.org/wiki/Crankcase

[BlitZ]

see bold

Thanks for clearing things up... stupid honda-tech.. ahahha I knew it didnt sound right when they said the crank case was the head

does it then mean you rings arent sealing right and that the air is escaping into crank case?
or it is just expected from air condensation...

[BlitZ]

Thanks tink...
Extract from wikipedia


Air ventilation

During normal operation, a small amount of unburned fuel and exhaust gases escape around the piston rings and enter the crankcase, referred to as "blow-by". [6] If these gases remained in the crankcase and condensed, the oil would become more diluted over time, decreasing its ability to lubricate. Condensed water would also cause parts of the engine to rust. [7] To counter this, a crankcase ventilation system exists to draw fresh air in from the air filter and expel the gases out the PCV valve.

If an engine is damaged or enters old age, gaps can form between the cylinder walls and pistons, resulting in larger amounts of blow-by than the crankcase ventilation system can handle. The gaps cause power loss, and ultimately mean that the engine needs to be rebuilt or replaced. [6] Symptoms of excessive blow-by include oil being pushed up into the air filter, out the dipstick[8], or out the PCV valve.

lets close this bugger

[tinkerbell]

it is funny, when i first start up my B20 - the clear PCV line that runs from the back of my block to the remote PCV canister gets condensation in it...

once the air gets hot though, this condensation disappears...