[335i E92]

Hi All

I have been following the below 2 threads on both N54tech & E90 USA with some alarm and wanted to give the UK a heads up on the situ.

http://www.e90post.com/forums/showthread.php?t=515581

http://www.n54tech.com/forums/showthread.php?t=12178

It seems that the lack of necessary flow caused by excessive tubing 90 Degree bends and clogged filters are causing back pressures on our turbo’s leading to possible turbo seal failures.

My AR Design OCC has only caught a 1/2 tea spoon of oil in 10'000 and the filter is caked in thick sticky oil vapour which is definitely restricting flow. I'm also running a stage 1 evolve tune and the car get its fair share of WOT action which surprises me how little oil it's caught

I'm seriously thinking of going back to stock. I know a few on here are running OCC, what are your thoughts?

H

[zltm089]

hmmm...sorry by OCC, do you mean Oil Catch Can???....

[335i E92]

Originally Posted by zltm089

hmmm...sorry by OCC, do you mean Oil Catch Can???....

Yes!!

[mithiral67]

i have very briefly looked over those threads, but took away the following.

1. The threads talk of ONE person having failed AFTER market turbos fail after running a long time on stock turbos with no issues.
2. The OP points out that the blown turbos are not the point of the threads, just that he noted additional positive pressure from the OCC.
3. We didnt need another thread for folks to argue in.

So, I am hard pressed that one person's failed AFTER market turbos can be concluded as a general fact.

[doughboy]

H, I've read these threads too I think its a lot of hype and worry about nothing. Darren wood routed our hoses without kinks (well he sorted yours first, then I went back to have mine tweaked)

There's no 'back pressure' on turbo's per say. What they're talking about it the possibility of breaching oil seals (anywhere on the engine, but mainly crank seals, not really turbo seals) due to restricted breather flow under boost conditions leading to an overpressurised crankcase thus forcing oil out of places it should not appear.

There's a guy on there running 20psi of boost and his engine is leaking all over the shop - but hey the cars only designed for 10psi!

If you're worried mate, take the feed hose off you OCC (engine / drivers side) and attach a short clean piece of hose, (bit of garden hose will do) and just blow through it. I bet you can blow as hard as you can without feeling any / much restriction. If you feel a restriction, take out the filter element and try it again to see if it makes any difference.

I'm suprised no one has suggested this simple test. I might give it a go at the weekend if I have time.

[zltm089]

How much boost are you running on Mike? Is the engine designed only for 10psi???? ....Anyone know how much psi is the stock boost?...

[335i E92]

As some of you know i don't proclaim to be the most technical amongst us and tbh a lot within the n54 thread went over my head!!

I just wanted to give a heads up as it seems like a heavily discussed subject on n54tech and something i though we should at least be aware of.

Mike, i've e-mailed Andrew regarding new filters and will let you know when i hear back. When you say blow through the occ via the tube on the can nearest the d/s to check flow. On my car that is the exit pipe from the cc so i will be blowing in the wrong direction. Is this what you meant?

I'm going in to Woods soon for an oil change, what alterations did he make to your OCC?

Cheers

H

[335i E92]

Originally Posted by zltm089

How much boost are you running on Mike? Is the engine designed only for 10psi???? ....Anyone know how much psi is the stock boost?...

I belive stock boost is 8.5psi.

[doughboy]

Roughly 8-10psi standard I think, dependant on weather etc.

H - I mean blow in normal flow direction into the filter - you might be correct about that being the passenger side, I'm not sure now!

Woods re-routed the breather hose to remove a kink that was occuring in the return hose. They said they had learnt that method when fitting it on your car and they changed mine to match yours (no charge of course).

So yours is already OK

[335i E92]

Originally Posted by doughboy

Roughly 8-10psi standard I think, dependant on weather etc.

H - I mean blow in normal flow direction into the filter - you might be correct about that being the passenger side, I'm not sure now!

Woods re-routed the breather hose to remove a kink that was occuring in the return hose. They said they had learnt that method when fitting it on your car and they changed mine to match yours (no charge of course).

So yours is already OK

Ok great, understud!! I'll check it tomorrow!!

[Yahoo]

Originally Posted by doughboy

Roughly 8-10psi standard I think, dependant on weather etc.

The stock ECU is programmed to boost up to 0.8 bar (11.6 psi) under certain elevations / barometric conditions.

[335i E92]

Just thought it right to put minds at rest after my alert.

Yesterday i took the rocker cover off the engine to expose the occ pipe work from the breather, no oil drip and everything looked in order.

I completely detached the pipe leading to the occ and drained it of oil as there is a section of the pipe that has to go up hill slightly to reach it.
This was definitely worth doing as there was a good 1/5 cup of oil in the pipe itself that didn't make it to the can.

Connected the pipe back to the can and blew down, given state of the below filter there was no resistance whatsoever and you could blow easily through the whole system.

Mike, if you read this the only thing we need to be aware of with the position on of our AR Design is the fact the pipe has to climb to get to the can.
As above, whilst my can never collected any oil there was a good amount in the piping, might be worth empting it every few months.

[doughboy]

Good work H.

[fastloop]

335i E92, what side is your OCC on? The passenger side option has a very long hose and it's really important that there are no dips in the hose run as otherwise it will collect oil there.

So much for oil vapor and a much shorter hose would have been preffered.

[335i E92]

Originally Posted by 335rocks

335i E92, what side is your OCC on? The passenger side option has a very long hose and it's really important that there are no dips in the hose run as otherwise it will collect oil there.

So much for oil vapor and a much shorter hose would have been preffered.

The can is on the passager side and the hose is about 3.5 feet long. It dips down then curves right up vertically to the can. In 10 months it hasn't collected hardly a drop. As stated in the last post it was ALL in the pipe.

I'll see if can shorten the pipe and get rid of the dip!!

TBH i did think it was strange that the oil feed in has a virtical section to feed oil in. Seems wrong and obviously the pressure isn't high enough to push it up

Thanks for the heads up, I'll have look after work tomoz and report back.

[doughboy]

H, my hoses are horizontal both sides where they leave the OCC, i'll get some pics later.

Also, I don't care if oil collects in the pipes a little, it still won't get through the filter and that's the important part.

[335i E92]

Originally Posted by doughboy

H, my hoses are horizontal both sides where they leave the OCC, i'll get some pics later.

Also, I don't care if oil collects in the pipes a little, it still won't get through the filter and that's the important part.

Hi Mike

My concern is that as the inlet pipe has a complete vertical section leading to the can of which the oil is failing to climb. My inlet connection on the can ponts straight down!!

Whilst the set up is still doing its job of not feeding oil back in to the system, if too much oil builds up in the pipe it will cause a significant restriction in air flow.

I'll take some pics tonight and post later also.

H

[335i E92]

Quick question!!

The closable valve at the bottom of the can where the oil collects, should this be closed tight to keep the system a closed loop or should it be open sligtly?

[doughboy]

H, just twist the 90deg elbows into the OCC, they're threaded and will rotate to what angle you want.

The valve needs to be SHUT, its the drain off point for oil.

[335i E92]

The reason i ask about the valve is that i noticed at the w'end that it was slightly open and was leaking air. I've closed it now, could i have done any harm?

As for the inlet pipe on the can, i know it pivots but the way the pipe has been routed to the can it has no choice but to point straight down. As i said I’ll take some photos tonight of how it was before i make the adjustments.

[doughboy]

Photos...

The feed pipe (from cylinder head) in on the left of the OCC.

The return pipe is the long one that goes back over the top of the engine to the air intake conection.

The feed pipe is fairly level, mostly downhill if anything, with a bit of a dip as it passes the air box.

[335i E92]

Top bloke, ta for the pics

Mine is set up completely different to yours!!

I'll take photos tonight, firstly my catch can has been bolted to the metal plate the other way around. My outlet is nearest the engine and the inlet is on the right fed coming up from underneath and the pipe dips right down. It like a the big dipper at Blackpool.

I’m going to switch it all around tonight and shorten the pipe accordingly. Can’t really blame Woods as this isn’t an OEM part and not something they are used to fitting.

I will however point it out to them when I go in for oil next month.

When you see the photo’s you’ll see that it’s not set up right at all.

Will the valve at the bottom of the catch can being slightly open and passing air have fooked anything up? It’s closed now but just concerned that it effectively hasn’t been running as a closed system for 10k.