Pcv System On 4Age

[the_van_can]

hi all,

 

So I have had the most annoying noise coming from my car latly, originally thought it was the water pump bearing but I was wrong.

I am getting some sort of negative pressure in my pcv system,

 

i think it's negative is negative normal? Anyway I pull the dipstick

while the car is running and whooosshhh, it sucks air from the dipstick and the sound goes away. So i gather the sound is from air being

sucked in through seals. I have a smallport 4age with a cut n shut inlet and this could be where the problem lies, but I've been using the

car for a year and a half till now and now the sound starts.

 

Bigger issue now, So I figure if its sucking air from the dipstick then something in the pcv system is not working properly, I have a catch can

setup and I thought I would unscrew the big bolt on top of the catch can while the car was running, and whooosshhh again sucking air so I leave

the car on for about 15 seconds like that, idle raised a little but then I noticed a puddle of oil leak from the front main seal, put the bolt back

on and babied the car home. I have no idea what this means any help is much appreciated.

[Trev]

http://www.rollaclub.com/board/index.php?showtopic=34517&st=0&p=378597&fromsearch=1entry378597

 

You need to run the pcv tube to the intake pipe as close to the throttle body as possible.

 

I would be inclined to change the seals.

[the_van_can]

cheers trev,

 

also trying to understand the seal giving way, so if it was under vaccume all the time then when I gave it a big breathing hole did it show the

true condition of the front main seal? because the seals wernt held in place with as much vaccume pressure.

[Trev]

Well it is weird that you say it was under vacuum as the PCV gets rid of positive crankcase pressure along with any oil that goes with it but if this were the case then your dipstick would be blowing out, are you sure it is under vacuum though?

 

Pressurising the seals would of forced them outwards making more of a seal but a different wear on the seal, taking the pressure away returns the seal to it's normal position allowing it to leak.

[the_van_can]

ok thanks trev much appreciated