Catch cans and PCV systems - Do we need them ?
25 September 2003, 06:37 AM
#61
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I found a Pure orange juice bottle worked better
Everytime i lifted the bonnet people asked what it was doing under there.
Rob
[Edited by tweenierob - 9/25/2003 6:38:15 AM]
Everytime i lifted the bonnet people asked what it was doing under there.
Rob
[Edited by tweenierob - 9/25/2003 6:38:15 AM]
25 September 2003, 08:37 PM
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01 October 2003, 01:11 PM
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So what is the collectives option on the various methods ?
I was thinking of blocking off the PCV valve. Then venting both rocker covers to air down beside the anti-roll bar.
I was thinking of blocking off the PCV valve. Then venting both rocker covers to air down beside the anti-roll bar.
01 October 2003, 02:46 PM
#65
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I have reservations doing it that way. It means that the oil returns from the heads have to go against the gas flow. At high rpm/boost this can delay the oil returns to the sump which in turn lowers the sump level........I don't need to explain the next bit 
There are some racers in the USA actually bleeding boost air into the camcovers and out the block vent (hence assisting oil flow) in order to stop the above happening.
This is a known issue on V8 cars when breathers are only taken from the covers. Many of them use mechanically driven crankcase vacuum systems to aid oil drain back.
Andy
There are some racers in the USA actually bleeding boost air into the camcovers and out the block vent (hence assisting oil flow) in order to stop the above happening.
This is a known issue on V8 cars when breathers are only taken from the covers. Many of them use mechanically driven crankcase vacuum systems to aid oil drain back.
Andy
01 October 2003, 11:29 PM
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Ken
Plug off the valve on the inlet manifold and throw away all the original pipes. Take 3 hoses, one from the connection on the block and one from each cam cover and lead them either to a catch tank or down to the ARB area to vent to atmosphere.
Andy
Plug off the valve on the inlet manifold and throw away all the original pipes. Take 3 hoses, one from the connection on the block and one from each cam cover and lead them either to a catch tank or down to the ARB area to vent to atmosphere.
Andy
02 October 2003, 10:52 AM
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Pardon my elbow but do you mean one of these?
http://www.autospeed.com/A_0338/P_1/article.html
The steel scourer thingies (and the bigger volume/slower fluid speed, promote dropout of the oil dropletts.
All seems a bit roll-royce considering a coke bottle can do the job. And it's possible to see if there's oil in it and it's possible to empty it easily.
Vindaloo.
http://www.autospeed.com/A_0338/P_1/article.html
The steel scourer thingies (and the bigger volume/slower fluid speed, promote dropout of the oil dropletts.
All seems a bit roll-royce considering a coke bottle can do the job. And it's possible to see if there's oil in it and it's possible to empty it easily.
Vindaloo.
04 October 2003, 10:20 PM
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Went for the hi-tech three bits of hose pointing at the road, should keep our biker friends on their toes 
Does anyone know the thread on the PCV valve ? At the moment I have bunged up the pipe with a large grub screw, but would like to remove the valve at some point in time.
Does anyone know the thread on the PCV valve ? At the moment I have bunged up the pipe with a large grub screw, but would like to remove the valve at some point in time.
16 May 2004, 08:54 PM
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bttt, interesting thread....anyone put a catch can, vented to atmosphere etc on a JDM STI7 to make sure octane rating stays high by not mixing oil with the gas and air ?
Anyone have pics on what pipes to vent to coke bottle or atmosphere and what things to clog up after removing hoses for a JDM STI7 ?
Cheers,
Ray
Anyone have pics on what pipes to vent to coke bottle or atmosphere and what things to clog up after removing hoses for a JDM STI7 ?
Cheers,
Ray
Last edited by Razor2001; 16 May 2004 at 10:21 PM.
17 May 2004, 01:55 AM
#76
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Drawing a small vaccuum on the crankcase should help with ring seal, aid oil return to the sump, help to evacuate blowby gasses and water vapours and reduce parasitic losses around the crank... So I guess its a fairly good idea. 
Of course, if you are using the manifold PCV to draw the vaccuum, an inline catch can would probably be a good idea.
Of course, if you are using the manifold PCV to draw the vaccuum, an inline catch can would probably be a good idea.
18 May 2004, 01:53 AM
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ok, I have read and re read all sorts of times this post .....is it fair to say that no special filters etc are needed, just three tubes to be run pointing towards ground and then plug the one entry to the block for when engine is on vacuum ? what about the 3 tubes venting towards the ground....won't they suck things into your engine on vacuum ?
Cheers,
Ray
PS: Wish I had some pics or a diagram....LOL
.....is it fair to say that no special filters etc are needed, just three tubes to be run pointing towards ground and then plug the one entry to the block for when engine is on vacuum ? what about the 3 tubes venting towards the ground....won't they suck things into your engine on vacuum ?Cheers,
Ray
PS: Wish I had some pics or a diagram....LOL
21 May 2004, 08:12 PM
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FWIW, on my UK98 I fed all 3 breathers into a catch tank and with my 12 mile drive to/from work every day got lots of water condensation in the long pipes running into the oil and resulting mayo in the pipes/ catch tank and oil filler, leading to comments suggesting my head gaskets had blown. I knew this was just my engine/journey combo and had happened for many months. Having recently changed the heads and confirming that the head gaskets were fine, I put small VTA filters on the cam cover vents (v short pipes) and left the c/case venting to the c/tank.
Result - no more mayo.
Stan
Result - no more mayo.
Stan
21 May 2004, 08:24 PM
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Hi StanS,
Thanks for that.
Can you help me a little please as I am no engine tech guru.
What are the:
3 breathers ? how do I identify them ?
VTA filter ? any pics, I assume this is a vent to atmosphere filter that lets air in and out of the pipes ? did you put this on all three pipes ?
OK, I have just re-read so 3 breathers, 1 = crank case (where is that one located?) that you stuck into the catch tank and then reconnected ?
other 2 = cam covers (where are they) that you vented to atmosphere with a little tube with a filter that lets air in and out at the end ?
Cheers,
Ray
Thanks for that.
Can you help me a little please as I am no engine tech guru.
What are the:
3 breathers ? how do I identify them ?
VTA filter ? any pics, I assume this is a vent to atmosphere filter that lets air in and out of the pipes ? did you put this on all three pipes ?
OK, I have just re-read
so 3 breathers, 1 = crank case (where is that one located?) that you stuck into the catch tank and then reconnected ?other 2 = cam covers (where are they) that you vented to atmosphere with a little tube with a filter that lets air in and out at the end ?
Cheers,
Ray
