Technical JTD Airbox / Oil Catch Tank / Vapour Trap

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Technical JTD Airbox / Oil Catch Tank / Vapour Trap

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May 18, 2008
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a mate was talking about his oil catch tank the other day at jap fest. he briefly expained what it did. what i understood was that it filters out the oil thats in the fumes that are fed from the oil breather pipe into the air intake.

would my stilo jtd benefit from having one, i've been looking at them on ebay and they're around £40.

any thoughts guys?

cheers
 
i've read alot about them on this Honda site:

http://images.google.co.uk/imgres?imgurl=http://www.gassavers.org/files/gassavers/pvc_catchcan0.jpg&imgrefurl=http://www.ek9.org/forum/engine/3486-oil-catch-tank.html&usg=__VuPIgMy5cOJFj5RrYH1Ntk3NtJs=&h=411&w=364&sz=52&hl=en&start=1&tbnid=akH1yVoOF-HTZM:&tbnh=125&tbnw=111&prev=/images%3Fq%3Doil%2Bcatch%2Btank%26gbv%3D2%26hl%3Den

sounds like theres two types, one to catch oil, and one to release crank pressure? the crank presure one seems to be conected to a PCV valve, do the JTD's have on of these? or is the crank pressure just a problem for the Hondas as they have Vetec engines?

any suggestions on what setup would be best for a jtd would be great, any guidance on where to feed which pipe would aslo be great.

cheers
 
Quite so (y)

Well worth checking it's in place though as we heard one horror story of the box falling down onto the road surface and being dragged along until he bottom was completely worn off (can't happen if your undertray is still in place).

Basically converted it into a road level gravel scoop intake for the engine :eek:
 
have a look on here
https://www.fiatforum.com/stilo/192665-pcv-valve-location-jtd-16v.html
mine has an oil seperator tank(item 1) its between back of engine and bulkhead this seems to be a smaller version of catch tank but drains oil back to sump and less oily air passes on down to turbo inlet, just have a look incase you already have one(follow breather pipe from oil filler neck or rocker cover).i planned on fitting an ebay tank to the outlet from original seperator and drain at intervals,but now i have it there isnt much space to put it in(i got a 1 litre tank) also if you do get one spend abit of time making some baffles for inside otherwise oily air will simply go in and straight out again.
 
just had a look on eper the 8v is different looks like no seperator tank.

cant see where the breather gets over to induction side if it does?but i think mine joins back onto pipe 11 i think it is on here.

p.s.stuart this diagram may help with your k+n filter change the maf is 7 ,
 
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Useful post (y)

The part that gets compressed when you try to open air box cover is #10 which is a corrugated plastic coupling between MAF and turbo. It will compress a bit with a lot of effort but what makes changing the air filter really easy is if this part is removed. You don't actually need to remove the MAF assembly at all but it's still a tricky and messy job.

On the 8v JTD vapour from crankcase is fed directly into turbo but the vapour/oil trap is directly underneath so is well positioned to catch any ejected oil which you don't really want going directly into the turbo.

Any oil caught this way isn't returned to the sump but would imagine it evaporates away over time due to constant air-flow across the connecting pipe :chin:
 
this is a home made baffle plate to split in/out goes approx 2/3rd down into tank and has holes in bottom half just incase it ever fills up to level of plate.
[URL=http://img507.imageshack.us/my.php?image=s1030431.jpg]
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this is profile at top,same as internal profile of lid.
[URL=http://img507.imageshack.us/my.php?image=s1030432.jpg]
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these are some other loose baffles to aid oil to condense(hopefully)without blocking airflow.
[URL=http://img516.imageshack.us/my.php?image=s1030433.jpg]
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this is baffles in place.
[URL=http://img222.imageshack.us/my.php?image=s1030434.jpg]
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none of the above is tested(until i can squeeze it in somewhere)but should be sound in theory.
hope these help.
 
depends why you want a catch tank i guess, i assumed their main use was in motorsport - and they're meant to have a larger capacity than the engines oil system, so in the event of an engine failure that leads to a pressurised sump, the oil is dumped into the tank and not on the track.

if you're on the road then i'd just vent it to atmosphere and be done with it.
 
depends why you want a catch tank i guess, i assumed their main use was in motorsport - and they're meant to have a larger capacity than the engines oil system, so in the event of an engine failure that leads to a pressurised sump, the oil is dumped into the tank and not on the track.
Ah! I see - so it's purely to keep the track clean

f you're on the road then i'd just vent it to atmosphere and be done with it.
Bit naughty :nono:

Do that in California and you'd want to check what the visiting hours are first :D
 
i would expect the pipe feeding the turbo to be at a lower pressure than atmosphere and therefore should be better at extracting excess crancase and rocker box pressure which can occur from engine blowby gas from piston rings, valve guides etc than venting to atmosphere. the problem is getting rid of the wet oily part of the breather gases before they are fed back into the system, as this mixed with soot from egr system can cause quite a sludge(bear in mind i have the problematic swirl valves in inlet manifold).
all systems on cars are built to a cost,just cos they havn't fitted something doesn't mean its not worth fitting.
also bear in mind with all tuned jtd's to whatever value above std will have higher values of blow by gases due to higher boost pressure and higher cylinder pressures etc.
on a std car probably not necessary, running extra 30-40% cant do any harm?
 
On the 8v JTD vapour from crankcase is fed directly into turbo but the vapour/oil trap is directly underneath so is well positioned to catch any ejected oil which you don't really want going directly into the turbo.

i havn't checked if mines still in tack lol. i dont see how the oil trap would work well... because my 8v JTD has the pipe going from the oil breather pipe on the engine cover going into the pipe that goes straight into the trubo, so wouldn't the turbo suck it all in before any oild falls into the trap?


the problem is getting rid of the wet oily part of the breather gases before they are fed back into the system

so would an oil catch tank be benficail if it could remove the oil faster than the oil trap can (if what i said above is right) ?

plus can anyone tell me why some have little filters on top and other don't? beacuse my understanding was that it uses a kind of suction power to remove the oilly vapours from the engine cover, seperate them and process the gas. but with the filter ontop, wouldn't you just suck air in from outside?

also how do you get the eper thing to work, not really sure what it is put it looks like there are some useful diagrams on there
 
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all systems on cars are built to a cost,just cos they havn't fitted something doesn't mean its not worth fitting.
But didn't you say the mJet already has a more advanced system than the std JTD (as it returns collected oil to the sump). I was just a bit surprised that you wanted to modify it.

bear in mind with all tuned jtd's to whatever value above std will have higher values of blow by gases due to higher boost pressure and higher cylinder pressures etc.
on a std car probably not necessary, running extra 30-40% cant do any harm?
Yes; the thought of oil being sucked into the turbo would certainly worry me although can't see a big issue with gases. Never had any issues even when taking it to the red line :devil:

I've heard stories of the vapour/oil trap being removed completely on some aftermarket inductions systems - now that would worry me (n)
 
this wikipedia page has alot of good info, and it kind of has an answer to sussex's question as to where the pcv valve is on is mjet. it does say at the top its a part of gasolin combustion engines

[ame]http://en.wikipedia.org/wiki/Pcv_valve[/ame]

so would the JTDs blow by etc be released from the oil breather pipe thing on the engine cover? but then that wouldn't be getting the gases from the crank case would it :-S
 
had first heard of a problem with tuned jtd 16v engines on the astra websites(their 1.9cdti is 1.9jtd 16v good as)

quote
We found lots of tiny issues with the higher power upgrade which slowly have now been Ironed out.

First Major issue is the Breather system on the CDTI .It is Ok for Standard power, but anything over a standard set up , used regularly hard will benefit from the Catch Tank we have in place on this Car.

The oil surges under higher boost pressures, causing the nose of the turbo to be flooded with oil as the breather vents into the Turbo inlet.

I developed now a system that will cut down oil into the inlet system by 80% by fitting a seperator pot which drains back in to the sump.
This is the single most important thing when tuning this engine.
end quote

this DAP catch tank looks a lot like the one fitted by fiat to my car
and the thread was tuning cdti to 220bhp-240bhp

stuart, my original seperator has feed from rockerbox and feed from crankcase going into tank and drain going from tank to sump and lastly a pipe feeding out that passes over to feed into turbo inlet pipe position as yours.this pipe is where im going to stick ebay tank inline hopefully just belt and braces i guess.
 
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i dont see how the oil trap would work well... because my 8v JTD has the pipe going from the oil breather pipe on the engine cover going into the pipe that goes straight into the trubo, so wouldn't the turbo suck it all in before any oild falls into the trap?
That's extremely valid but at some point you just have to trust the engineers that designed the JTD aren't stupid. I'd imagine Alfa use a very similar system.

If you look carefully, the outlet to the oil trap is directly opposite and underneath the crank breather pipe (the diagram looks a little wrong to me) so it's easy to imagine oil being blasted across the path of the incoming air stream but what happens under say full boost is another matter :chin:

Like I say, you just have to take some things on trust. You don't hear of too many turbo failures (even when mapped) so they must have got something right (y)
 
Well when i had my escort td's both the 90bhp intercoolers, The breather from the rocker cover used to feed into the inlet side of the turbo about two inches away from the vanes of the turbo.
The first one i blanked off and ran it too 150,000 miles with no ill effects and the 2nd one i didnt touch and ran that to 130,000 and never touched the engines at all.

Now having looked at the set up on the jtd i dont quite get the intercooler setup or the airfilter as it appears to be a split intake and i was aways under the impression that all the air that goes into a turbo was cooled but its not????????????
Would it not be better for the air to all go through the intercooler and the turbo???

Mind having said that the escorts aways had the intercooler after the turbo which always seemed odd but it seemed to work ok.

Oh and just a slight change of subject this is my current air filter set up and no beep beeps at all.
DSCF0109.jpg
 
i guess your refering to the pipe and box under that non std cone filter?i think thats the vapour trap and dont know why its there unless its for all the oil residue or possibly water from that filter(as that is close to floor and open to elements)to run down into this box and then dry out rather than procede into turbo inlet.all outlet from turbo goes to intercooler but pipes not shown in that pic.
re- eper i tend to find this link works most times i get straight on.
http://212.187.114.126:7080/navi?CO...INT_MODE=0&EPER_CAT=SP&GUI_LANG=3&WINDOW_ID=1
checked alfa systems(alfa 159)and all parts look as fiat except different air filter box layout and turbo intake pipes.1.9 8v =no seperator tank
1.9 16v=same tank as fiat 16v 2.4 20v=same tank as fiat 16v
 
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