PCV pressure...

Post 676670 by M-R-P on 2014-01-02 15:26:45

Just wondering... Is there any pressure in the PCV at idle? I've been buggering about with my PCV system recently (all will become clear later but that's for another thread) and noticed that, at idle, there's not even a whisp coming through the pipe that connects to the inlet (maf to turbo) pipe. I know the PCV system is clear and the engine is healthy. The PCV gathers pressure from a small banjo bolt on the inlet manifold and whatever blow-by occurs in the block but to have nothing at idle seems a little weird? Or am I just looking for something that shouldn't be there? I'm happy there's nothing wrong but thought I'd bung the question out there for the sake of something new to talk about :)

Post 676678 by p fandango on 2014-01-02 15:52:36

i've binned BT's PCV, but the catch-tank always has quite a noticable outlet even on tickover

Post 676679 by M-R-P on 2014-01-02 15:53:59

[QUOTE=p fandango;676678]i've binned BT's PCV, but the catch-tank always has quite a noticable outlet even on tickover[/QUOTE] Is it solely fed from the block? There's no banjo bolt thingy on the early manifold is there?

Post 676682 by oblark on 2014-01-02 15:58:28

The banjo on the inlet manifold is for a vacuum I think :)

Post 676683 by p fandango on 2014-01-02 16:01:44

[QUOTE=M-R-P;676679]Is it solely fed from the block? There's no banjo bolt thingy on the early manifold is there?[/QUOTE] theirs nothing coming off the manifold, but it is fed from a port lower down on the block next to the PCV tank. you can see the 2 inlets for the PCV plumbed with silver tube here which go to feed the catch tank, the bottom outlet from the PCV is bunged

Post 676685 by M-R-P on 2014-01-02 16:04:09

[QUOTE=oblark;676682]The banjo on the inlet manifold is for a vacuum I think :)[/QUOTE] It's not valved, so it'll be doing both ;)

Post 676686 by M-R-P on 2014-01-02 16:05:55

[QUOTE=p fandango;676683]theirs nothing coming off the manifold, but it is fed from a port lower down on the block next to the PCV tank. you can see the 2 inlets for the PCV plumbed with silver tube here which go to feed the catch tank, the bottom outlet from the PCV is bunged Interesting. I know how the PCV works, this is kinda the reason for the thread. I have a feeling there's a small leak in one of the connections I added when fitting the custom maf to turbo pipe. I'll investigate that later.

Post 676688 by M-R-P on 2014-01-02 16:07:03

[QUOTE=p fandango;676683]theirs nothing coming off the manifold, but it is fed from a port lower down on the block next to the PCV tank. you can see the 2 inlets for the PCV plumbed with silver tube here which go to feed the catch tank, the bottom outlet from the PCV is bunged [/QUOTE] Interesting. I know how the PCV works, this is kinda the reason for the thread. I have a feeling there's a small leak in one of the connections I added when fitting the custom maf to turbo pipe. I'll investigate that later.

Post 676692 by oblark on 2014-01-02 16:14:38

The P2 PCV is slightly different to the 850 PCV. The part in the red circle conects to the under side of the inlet manifold [ATTACH=CONFIG]23400[/ATTACH]

Post 676695 by M-R-P on 2014-01-02 16:28:40

[QUOTE=oblark;676692]The P2 PCV is slightly different to the 850 PCV. The part in the red circle conects to the under side of the inlet manifold [ATTACH=CONFIG]23400[/ATTACH][/QUOTE] Indeed. I took my entire PCV system off and found it to be clean as the proverbial whistle. Turned out to be that banjo bolt causing the problem :) I'm presuming yours is blocked-off Rob?

Post 676701 by oblark on 2014-01-02 16:40:48

The pipe that comes off the pcv and goes around the engine is not on mine, the pcv now vents to atmosphere :)

Post 676704 by deathrider311271 on 2014-01-02 16:56:26

if its the one that screws in the bottom off the manifold as on all ME7 cars then Tim filled mine with chemical metal as he said its no use

Post 676708 by Mongo on 2014-01-02 17:16:32

Mate pcv is a pain. Ive had untold problems with oil leaking out my oil filler cap im now running 2 catch cans 1st is for the main block 2nd is for cam cover and iv drilled and taped my oil cap all 19mm hoses plus my cam cover has been baffled at the oil filler hole and still it leaks oil through the cap. Impossible lol

Post 676711 by JT on 2014-01-02 17:38:45

Mine was also leaking out of the oil cap! IPD advise the seal is changed at every service or replace it with one of their 'uprated' versions

Post 676715 by Mongo on 2014-01-02 17:50:17

I know i have tried everything lol im now using a oil resistant 4ply hose cut out to wedge between the cap and cover. Its a bodge but its slowed it down. I have not tried the uprated one from ipd yet i must admit i will order one.

Post 676717 by M-R-P on 2014-01-02 17:57:48

[QUOTE=deathrider311271;676704]if its the one that screws in the bottom off the manifold as on all ME7 cars then Tim filled mine with chemical metal as he said its no use[/QUOTE] when I cleaned my pcv (lots of smoke from the dipstick etc) the only blockage was in that banjo bolt. after clearing it, no more smoke. perhaps it's just a coincidence. anyway, I'll sort the leaky connection later (if there is one) and see if there's any pressure in the pipe. I'm presuming it's not a problem if there isn't any pressure?

Post 676721 by oblark on 2014-01-02 18:17:58

[QUOTE=M-R-P;676717]when I cleaned my pcv (lots of smoke from the dipstick etc) the only blockage was in that banjo bolt. [COLOR="#FF0000"]after clearing it, no more smoke[/COLOR]. perhaps it's just a coincidence. anyway, I'll sort the leaky connection later (if there is one) and see if there's any pressure in the pipe. I'm presuming it's not a problem if there isn't any pressure?[/QUOTE] As the banjo bolt is on the inlet manifold whem the engine is running it will suck the smoke into the engine. :)

Post 676723 by M-R-P on 2014-01-02 18:23:08

[QUOTE=oblark;676721]As the banjo bolt is on the inlet manifold whem the engine is running it will suck the smoke into the engine. :)[/QUOTE] it's only a very tiny hole... (said the bishop to the actress) I can't see it making that much difference but I like your logic.

Post 676726 by oblark on 2014-01-02 18:28:38

[QUOTE=M-R-P;676723][COLOR="#FF0000"]it's only a very tiny hole[/COLOR]... (said the bishop to the actress) I can't see it making that much difference but I like your logic.[/QUOTE] On all the S60R`s i`ve broken the hole in the banjo bolt was normal for thet size of bolt :)

Post 676731 by M-R-P on 2014-01-02 18:34:45

about 3 or 4mm iirc

Post 676733 by oblark on 2014-01-02 18:39:36

[QUOTE=M-R-P;676731]about 3 or 4mm iirc[/QUOTE] Yeah :) about that.

Post 676739 by JT on 2014-01-02 19:10:24

[QUOTE=Mongo;676715]I know i have tried everything lol im now using a oil resistant 4ply hose cut out to wedge between the cap and cover. Its a bodge but its slowed it down. I have not tried the uprated one from ipd yet i must admit i will order one.[/QUOTE] I ordered 1, but my current engine doesnt leak! :doh: lol

Post 676740 by Harvey on 2014-01-02 19:12:55

The banjo bolt at the inlet manifold only comes in to play when the engine is at tickover as there is a vacuum at the inlet manifold as the turbo is not working ( no boost ),so it sucks the blow by gasses out from the block throught the banjo bolt into the clyinders ,the pct nipple that plugs into the turbo inlet pipe is not working also because the turbo is not sucking air in so no vacuum present there,that's why they also heat the banjo pipe with the engine water pipe work. But when the turbo is on boost the inlet manifold is under pressure so the pressure there is blowing air throught the banjo bolt back to the fire trap box,but now the the pct valve is under vacuum from the turbo via the inlet pipe so it is now sucking the blow by gasses throught the turbo,pipework back to the inlet manifold under boost this time.

Post 676744 by M-R-P on 2014-01-02 19:23:23

other than the firetrap not existing on any 5-pot past 1996 and the ptc nipple infact is merely a heater, that explanation confirms what I thought to be the case. Cheerz Harv ;) (I know, pedantic git ain't I lol)

Post 676745 by oblark on 2014-01-02 19:24:42

[QUOTE=Harvey;676740]The banjo bolt at the inlet manifold only comes in to play when the engine is at tickover as there is a vacuum at the inlet manifold as the turbo is not working ( no boost ),so it sucks the blow by gasses out from the block throught the banjo bolt into the clyinders ,the pct nipple that plugs into the turbo inlet pipe is not working also because the turbo is not sucking air in so no vacuum present there,that's why they also heat the banjo pipe with the engine water pipe work. But when the turbo is on boost the inlet manifold is under pressure so the pressure there is blowing air throught the banjo bolt back to the fire trap box,but now the the pct valve is under vacuum from the turbo via the inlet pipe so it is now sucking the blow by gasses throught the turbo,pipework back to the inlet manifold under boost this time.[/QUOTE] That`s what I said :)