To Breathe or Block?

[Robbbyg]

3.0 930
with added
3.3 intake manifold
3.3 BOV assembly
Intercooler

Hi when i reassembled the bits i also installed a BMC Air Intake setup,


There was a hose going from a pipe next to the turbo up to where the Air Filter used to be, was this hose in a vacuum? or does it simply breathe and doesnt matter where i route it with a filter on it? or is it best to block it off completely?, there are no references on this matter ive looked on the BMC website,

(ive pulled the blue silicone back with my hand it is not bent)


You can see the pipe here..
Thoughts?

[Hams930T]

You need to plug that.

[WERK I]

It's the breather line coming off the turbocharger drip tank. I would put a line in from that point back to the air cleaner......or you can put a breather/filter on it. Don't leave it as it is as water could drip down into it and contaminate the oil in the tank.

[Robbbyg]

I did have a hose an filter on it i only removed it to show in photo.

But we have a Tie! ??

I can Plug it.
I can also breathe it.

????? which??

Would it be ok if i blocked it on Mondays, Wednesdays and Fridays,
And Breathe it Tueadays, Thursdays, and Saturdays..

And just leave it with nothing on it on Sundays??

[Ronnie's.930]

Originally Posted by Robbbyg

But we have a Tie! ??

I can Plug it.
I can also breathe it.

????? which??

Ha! Yep, and that "tie" bit seems to be pretty normal even when it comes to tech info (lots of differing opinions on what "works")!

The reason for the tie is this - the turbo, oil drip tank seems to work both ways (or like Paul "goes both ways" ) . . . the OEM one is vented and most aftermarket ones, including custom built ones you see on here, are not vented. The unvented ones do not cause problems for 99% of the people that use them (including me), but about 1% think the lack of venting causes oil to leak past the turbo shaft seals. Brian (RarlyL8) makes a tank with vent options, and points out that the vent can actually help "show" a problem (for example, oil not pumping out of the tank properly).

So there you have it, but given that you have the OEM vented tank in place, and like WERK suggested, why not continue to vent it as designed?

[Robbbyg]

She breathes,,
But it fell off today (little bmc filter) up the road somewhere....

Ill get there

[ertech]

Funny I was going to buy a fitter today for it before I install my engine tomorow.
So I think after reading this will plug it....
Unless I hear more negatives
Thanks

[ertech]

So what is the concesus?
Thanks

[Speedy Squirrel]

The turbo oil pump turns at camshaft speed. This is not ideal from a scavenging point of view, so a compromise is made. The pump pumps too much at high engine speed, and too little at idle. If you do not have a vent, and you idle for long periods of time, the resulting vacuum can slow the scavenging to the point that the tank can start to fill up. If you idle a really long time, the bearing housing on the turbo will start to back up with oil and you may get some smoking.

In practice I think this scenario is uncommon, and thus gives the appearance that a vent is not needed.

[Robbbyg]

Funny you should post this as ive just developed a problem with the breathe line from the Oil Turbo Tank,

Yesterday while driving back from the shops i had smoking and when i got back i had oil everywhere in the engine bay where it had sprayed from the Breather i dont know why it started to do this as i didnt change anything relating to Oil as far as i know,

Before i had his problem all i did was remove a crimped Smog injection and replaced with PLugs, i also took off the exhaust manifolds and checked the gaskets and resealed as i had a small leak at the middle pipe, engine system pressure i have not checked neither have i checked system oil pressure as i dont have the gear and taking it into a shop is out of the question,

I have checked compression but they were all on 105 psi give or take 1 psi i havent checked them when engine is warm though but as there was little/no variation across the board i dont think it is necessary.

So the oil is leaking /spraying against gravity uphill to exit the filter,
Can ethe type of oil used cause this?

What is the best thing i should i do to troubleshoot/alleviate this symptom?

heres a pic i just took today i havent driven the engine since i noticed the problem,

second pic shows the hose layout from the breather

could using a smaller diameter than dare i say it (factory) hose cause this?

[Robbbyg]

Just a thought would it be better to extend the breather line?
originally it extended to to the top back of the engine to the where the Airbox was probably about 3 feet

[quattrorunner]

Deviating from the factory are we?
I'm more worried about your scavenge pump.

[quattrorunner]

The way you check that is to disconnect the pump suction line from the tank. Let the oil flow from the tank into a big bowel and let the scavenge pump draw from the bowel. Let's hope it keeps up.

[Robbbyg]

Originally Posted by quattrorunner

Deviating from the factory are we?
I'm more worried about your scavenge pump.

Yes and see what happens when i do? lol

[Robbbyg]

Originally Posted by quattrorunner

The way you check that is to disconnect the pump suction line from the tank. Let the oil flow from the tank into a big bowel and let the scavenge pump draw from the bowel. Let's hope it keeps up.

You mean the big fat oil line from the MAIN Engine oil Tank? disconnect that one ?
And If so do i disconnect A or B ?

What causes them to fail if thats the case here? aren't they mechanical? can they be fixed at home?

[Robbbyg]

Can you also tell me which pipe on the Turbo oil feeder is the scavenge line?

This is not looking to be a happy job

[quattrorunner]

Originally Posted by Robbbyg

You mean the big fat oil line from the MAIN Engine oil Tank? disconnect that one ?
And If so do i disconnect A or B ?

What causes them to fail if thats the case here? aren't they mechanical? can they be fixed at home?

No!!!!! Don't disconnect those at all.

I'm talking about the scavenge lint to turbo tank. Disconnect that and let the turbo tank drain into a bowel.

[quattrorunner]

Follow the line to the scavenge pump and use that line to draw from the bowel. You might need to add some rubber line to the hard line to allow it to dip into the bowel.
Hey......did you paint the oil tank? Porsche most definitely doe not do that!

[quattrorunner]

I'm falling for it guys. I know we're being punked here. It's just too much.

[Robbbyg]

Originally Posted by quattrorunner

I'm falling for it guys. I know we're being punked here. It's just too much.

lol

Im man enough to inform you that my questions are completely legitimate i honestly dont know , how could i, Ive never done this task b4.

But b im doing it now, i just hope I am not being punked and this is completely unnecessary!, ive just turned 90 and my 2 tonne trolley jack is getting hard to push around not counting the fact that i have to get on my back and under the flippin car again.