Whats this?? crankcase ventilation??

[Upon_1]

c:\desktop\pa070001.jpg
c:\desktop\pa070002.jpg
c:\desktop\pa070003.jpg

hey fellas,

I noticed a vaccum leak sound the other day and i have found this pipe in the pictures broken off, i would like to know what the pipe is used for??

Any help is appriciated

Cheers

[Upon_1]

seem's i dont know how to post pics.......

the pipe is on the lower left hand side of the throttle body and it connects to the top of the rocker covers??

Any feedback?????

[Ryzz]

You have to upload the pics onto a web server mate, Harroc & VooDoo both have guides on how to do this for their servers

[Wingnut]

I think the tube you are refering to is for the crank case ventilation. Without seeing the pictures, the tube that has split connects onto a plastic tube that runs down the drivers side cylinder head, to a y piece at the rear of the engine? If so, you can purchase a small piece of hose, cut it to length and replace. The holden dealers sell a replacement part, which costs about $80, and includes the plastic tubes (which you wont need unless you break it). I had to replace the same bit on my VXSS only recently, the old tube will slide off the throttle body without too much hassle.

[BLACK 346]

seem's i dont know how to post pics.......

the pipe is on the lower left hand side of the throttle body and it connects to the top of the rocker covers??

Any feedback?????

If it is PCV it doesn't actually connect to the T/B,
but to the intake manifold behind the T/B. Only
hoses that connect to the T/B are coolant hoses
and they are at the base on the Left and Right
sides. If it is LHS as you are facing the engine
and goes from the Intake manifold and runs
down the side of the motor as mentioned by
Wingnut above, then it would be PCV.

[Upon_1]

thanks heaps for your feed back guys. iv temporary fixed if with a bit of conduit and hi temp silcon, see how its goes before a bother gettin the part

thanks again cheers

[my_Berlina]

Crank case ventilation is fairly important. As the rings don't seal perfectly against the cylinder walls, there is always some blow-by gasses that slip past the rings. These include some nasty gasses and even some unburnt fuel. In the old days it was a basic ventilation. However this allowed some of the nasties (including some organic acids) to collect in the crank case. So one good solution was to connect a hose from the crank case to the inlet manifold, using the vacuum of the engine to suck the nasty gasses out and run them through the engine - thus Positive Crankcase Ventilation. To limit the flow there is a PCV valve in that path. It is still possible to suck more gas into the inlet than there is blow-by so a filtered breather is required. So that dirty air is not getting into the engine. Ofcause there are times when there is more blow-by than the engine is sucking so there will be some of the nasty gasses escaping out the breather - this ofcause upset the polution nazis, so in the 70s the breather was moved into the air intake. In the old carbie cars it normally plugged into the air filter housing on top of the carb. In our cars it plugs into a connector on the TB that is plumbed through to a port infront of the throttle blade (exposed to approx atmospheric pressure - not manifold vacuum).

In our cars, the circuit is:
* Connection at Throttle body (the air travelling through here has already been metered)
* Black rubber hose to front of right hand rocker cover
* Through crank case
* Connections at back of each rocker cover
* Y-connector at back of engine (part of hard plastic pipe work that comes up to near the front of the right hand bank
* Ruber hose to PCV Valve
* PCV Valve
* Rubber hose to manifold (if this one gets a leak the you end up with un-metered and un-regulated air into the manifold. and end up running lean - particularly at idle.)

http://www.dd.id.au/LS1/PCV/PCV_Points.jpg

Dave !

[BLACK 346]

Crank case ventilation is fairly important. As the rings don't seal perfectly against the cylinder walls, there is always some blow-by gasses that slip past the rings. These include some nasty gasses and even some unburnt fuel. In the old days it was a basic ventilation. However this allowed some of the nasties (including some organic acids) to collect in the crank case. So one good solution was to connect a hose from the crank case to the inlet manifold, using the vacuum of the engine to suck the nasty gasses out and run them through the engine - thus Positive Crankcase Ventilation. To limit the flow there is a PCV valve in that path. It is still possible to suck more gas into the inlet than there is blow-by so a filtered breather is required. So that dirty air is not getting into the engine. Ofcause there are times when there is more blow-by than the engine is sucking so there will be some of the nasty gasses escaping out the breather - this ofcause upset the polution nazis, so in the 70s the breather was moved into the air intake. In the old carbie cars it normally plugged into the air filter housing on top of the carb. In our cars it plugs into a connector on the TB that is plumbed through to a port infront of the throttle blade (exposed to approx atmospheric pressure - not manifold vacuum).

In our cars, the circuit is:
* Connection at Throttle body (the air travelling through here has already been metered)
* Black rubber hose to front of right hand rocker cover
* Through crank case
* Connections at back of each rocker cover
* Y-connector at back of engine (part of hard plastic pipe work that comes up to near the front of the right hand bank
* Ruber hose to PCV Valve
* PCV Valve
* Rubber hose to manifold (if this one gets a leak the you end up with un-metered and un-regulated air into the manifold. and end up running lean - particularly at idle.)

http://www.dd.id.au/LS1/PCV/PCV_Points.jpg

Dave !

Good post, and I stand corrected about the pipe going
to the top of the T/B, memory is getting bad.