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Toyota Owners Club - Australia > Toyota Models > Corolla / Corolla Sportivo
spillige
just wanted to throw this question out there, is it posible to remove the pcv system and replace it with a traditionl setup? or is there no point to this, im guessing the pcv system is better cause it uses a vacuem system... but would it hurt to change it to traditional setup?
CHA54
what's your definition of a traditional pcv setup?

Every Toyota Twincam I can think of from the last 20 years or so has the PCV routed to manifold vacuum.
spillige
what im asking is can i remove the pcv valve all together, and replace the pcv valve setup for a straight thru system, will this harm the motor?
qkslvr
QUOTE (spillige @ Nov 10 2008, 03:54 PM) *
what im asking is can i remove the pcv valve all together, and replace the pcv valve setup for a straight thru system, will this harm the motor?


Straight through?
CHA54
leave the valve alone.
spillige
will do...
RODNZ
QUOTE (spillige @ Nov 10 2008, 04:06 AM) *
just wanted to throw this question out there, is it posible to remove the pcv system and replace it with a traditionl setup? or is there no point to this, im guessing the pcv system is better cause it uses a vacuem system... but would it hurt to change it to traditional setup?


Whats the traditional setup?
CHA54
a traditional setup is also the PCV routed to manifold vacuum.

ZZ's have the cam inlet breather routed pre-throttle and the pcv outlet routed post-throttle
spillige
i know how the system works, just asking can i remove the valve and run my hoses derectly to a breather can with out a vaceum, but im thinking this wouldnt be very effective
Hiro Protagonist
QUOTE (spillige @ Nov 10 2008, 10:55 PM) *
i know how the system works, just asking can i remove the valve and run my hoses derectly to a breather can with out a vaceum, but im thinking this wouldnt be very effective


Considering the vacuum is the thing providing the suckage, bypassing the manifold and just plumbing it to a catch can will do jack all. Something has to suck the vapour out of the cam cover, it isn't just going to go by itself.
the_random_hero
QUOTE (Hiro Protagonist @ Nov 10 2008, 11:13 PM) *
QUOTE (spillige @ Nov 10 2008, 10:55 PM) *
i know how the system works, just asking can i remove the valve and run my hoses derectly to a breather can with out a vaceum, but im thinking this wouldnt be very effective


Considering the vacuum is the thing providing the suckage, bypassing the manifold and just plumbing it to a catch can will do jack all. Something has to suck the vapour out of the cam cover, it isn't just going to go by itself.



Actually, the whole point of the breathers on the cam cover is to prevent the build-up of positive pressure in the head. If there's no restrictions between the breather and the catch can, any positively-pressured gas will flow out of it's own accord.
spillage - leave the system alone, or do a catch can plumbed back into your intake manifold properly.
spillige
ill be leaving it how it is just intergrating the oil catch on to it, one thing i dont get is why they made the out let on the valve so small yet the plenum nozzle is 15mm
Hiro Protagonist
QUOTE (the_random_hero @ Nov 12 2008, 08:26 PM) *
QUOTE (Hiro Protagonist @ Nov 10 2008, 11:13 PM) *
QUOTE (spillige @ Nov 10 2008, 10:55 PM) *
i know how the system works, just asking can i remove the valve and run my hoses derectly to a breather can with out a vaceum, but im thinking this wouldnt be very effective


Considering the vacuum is the thing providing the suckage, bypassing the manifold and just plumbing it to a catch can will do jack all. Something has to suck the vapour out of the cam cover, it isn't just going to go by itself.



Actually, the whole point of the breathers on the cam cover is to prevent the build-up of positive pressure in the head. If there's no restrictions between the breather and the catch can, any positively-pressured gas will flow out of it's own accord.
spillage - leave the system alone, or do a catch can plumbed back into your intake manifold properly.


Actually, on most cars the breather is there to draw air into the cam cover for the PCV system. Intake air goes into the cam cover, circulates through the engine, mixes with crank-case blow-by gases, and then when there is a large manifold vacuum the PCV valve opens and this mixture gets sucked into the manifold and then the engine, and burnt. That's how the PCV system works, PCV standing for Positive Crankcase Ventilation. If there was no breather, then no air could get drawn into the covers and the PCV circulation system wouldn't work, and the vapours would stay in the crankcase and mix with the oil (a bad thing).

Some people don't like the idea of the blow-by/oil vapour blow-by getting re-circulated into the engine, so they fit an oil catch can on the PCV hose, which strains out the oil whilst still flowing air (basically a filter). This oil can get returned to the sump, or just periodically emptied. The gas output of the catch-can gets routed back into the intake manifold through the PCV valve.
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