What about an oil catch can? (oil separator)

[exmowner]

After 4000 supercharged kms my air filter looked like it needed a clean/re-oil.

Taking J2m's advice I decided to buy a spare filter to have on hand and went ahead and replaced it.

I also added a K&N pre charger (RE-0810PK Filter Wraps)

This should help keep some dirt and blow by water from getting onto the filter!

Anyways while I had the liner off i decided to inspect the car to make sure nothing looked out of place. I swiped the inside of the supercharger inlet tube with a rag and to my surprise it was coated with engine oil....

This got me thinking and I realized that with the added crank pressure, oil was actually getting syphoned out of the engine threw the PCV valve and getting into the supercharger inlet pipe.

I'm not exactly happy about this extra oil finding its was into the engine. Ive read that oil sucked in threw the intake (blow by) actually reduces octane.

After some searching I came up with an oil catch can or oil separator to help keep oil off my intercooler and out of my intake.

radiumauto(dote)com sell a kit for an e46 m3 but it looks like it would also work great for the e92 m3.

I'll contact them in the morning and if it checks out i'll report back with my findings. I think it's something supercharged m owners should invest in.

Alex

[s65e90]

any catch can setup is a good idea to keep the intake clean esp. on a boosted setup. Any can will work just place it inline to the intake from the PCV; you can also just run a line to the ground (not as friendly for emissions/environment). I would also consider the PCV setup if it gets really bad but I don't think it should. You can tech. eliminate the PCV setup altogether

[s65e90]

also you can use a small clear carburator in line fuel filter spliced into the hose going to the intake pipe. this will filter some of the oil and prevent the intake from getting gummed up. (also cheap at like $ 5)

[aus]

Try to get a can with steel wool in it. The N54 catch cans with a metal filter didn't do anything for catching oil.

[exmowner]

Originally Posted by aus

Try to get a can with steel wool in it. The N54 catch cans with a metal filter didn't do anything for catching oil.

thanks for the tip!

[pbonsalb]

I have found catch cans are mixed. Some are empty and just for looks. Some have a grate inside and some have a filter inside. Massive suction, such as from a supercharger or turbo, will suck more oil vapor in than the stock system can filter out. Good luck with your search and let us know what you find.

[exmowner]

Originally Posted by pbonsalb

I have found catch cans are mixed. Some are empty and just for looks. Some have a grate inside and some have a filter inside. Massive suction, such as from a supercharger or turbo, will suck more oil vapor in than the stock system can filter out. Good luck with your search and let us know what you find.

I stumbled on this by accident, since supercharging my m I've been paying closer attention to maintenance.

Will do, placed an order today and I'll get a DIY together once it arrives.

Alex

[s65e90]

Originally Posted by pbonsalb

I have found catch cans are mixed. Some are empty and just for looks. Some have a grate inside and some have a filter inside. Massive suction, such as from a supercharger or turbo, will suck more oil vapor in than the stock system can filter out. Good luck with your search and let us know what you find.

if that's the case then you don't route back into the intake at all and go straight to a catch can only or like I said right to the ground and you won't have any more oil into the intake tract. Again the PCV setup can also be eliminated altogether if needed

[exmowner]

Originally Posted by s65e90

if that's the case then you don't route back into the intake at all and go straight to a catch can only or like I said right to the ground and you won't have any more oil into the intake tract. Again the PCV setup can also be eliminated altogether if needed

I'm confused... If the PCV is eliminated what will happen if there is excessive crank pressure?

[s65e90]

Originally Posted by exmowner

I'm confused... If the PCV is eliminated what will happen if there is excessive crank pressure?

it's not really advised unless you have excess crankcase pressure and then there's probaly/maybe other issues.


I am confused as to your post though. the pcv is a one way check valve. It can blow pressure out but can't suck in. W/out one (or a hollowed out one) you would have marginal vacuum at idle but it would work the same way pushing excess pressure out

[pbonsalb]

Not sure about the E90M3, but on some other BMWs, the crankcase vent does not use a PVC valve that incorporates a check valve. There is simply a vent from the valve cover to what is essentially a catch can with a return to the intake so vacuum sucks the vapor into the motor, and the can drains into the crankcase. With boost, a check valve is inserted into the connection to the intake so the catch can cannot see boost or the system is removed and a vent to atmosphere is used. Vacuum is more effective that atmospheric pressure at extracting crankcase pressure, though venting to atmosphere does seem to work.

[s65e90]

Originally Posted by pbonsalb

Not sure about the E90M3, but on some other BMWs, the crankcase vent does not use a PVC valve that incorporates a check valve. There is simply a vent from the valve cover to what is essentially a catch can with a return to the intake so vacuum sucks the vapor into the motor, and the can drains into the crankcase. With boost, a check valve is inserted into the connection to the intake so the catch can cannot see boost or the system is removed and a vent to atmosphere is used. Vacuum is more effective that atmospheric pressure at extracting crankcase pressure, though venting to atmosphere does seem to work.

Yeah may be diff on e9x, but I had thought there is a check valve behind intake setup; again may be wrong though. either way, emissions are the root of the nonsens when you can really get away w/ running an open line to the atmosphere.

[pbonsalb]

The open vent works, but can transmit smell into the passenger compartment. A vacuum operated system is better because it will pull more air and any pressure in the crankcase costs power. You do see plenty of high power old muscle cars with open vents (breather filters on the valve covers), but the really serious people use belt driven vacuum pumps designed for this purpose. Electric pumps have mixed results -- they typically are not powerful enough.

I am currently running an exhaust scavenge on my turbo E36M3; I have also run an open vent, a breather vent and a catch can. The only one I did not like was the recirculating catch can -- it still pulled oil vapor through into the intake manifold because the suction from the supercharger inlet (before the turbo, I was running a Vortech T Trim) was so strong.

[s65e90]

Originally Posted by pbonsalb

The open vent works, but can transmit smell into the passenger compartment. A vacuum operated system is better because it will pull more air and any pressure in the crankcase costs power. You do see plenty of high power old muscle cars with open vents (breather filters on the valve covers), but the really serious people use belt driven vacuum pumps designed for this purpose. Electric pumps have mixed results -- they typically are not powerful enough.

I am currently running an exhaust scavenge on my turbo E36M3; I have also run an open vent, a breather vent and a catch can. The only one I did not like was the recirculating catch can -- it still pulled oil vapor through into the intake manifold because the suction from the supercharger inlet (before the turbo, I was running a Vortech T Trim) was so strong.

I agree the recirculating in line catch can still isn't 100% for the cost/hassle. I like the exhaust setup though; running like a Moroso setup? into the downpipe?

[pbonsalb]

Yes, but I use the similar one by Vibrant and mine is after the downpipe. The downside here is that the oil vapor goes in the exhaust and periodically when you get on it hard, it blows a good puff of smoke out the back. That can be slightly embarrassing but does not seriously bother me.

[GIdriver]

I'm kind of lost here. Excuse my ignorance but, how does this happens? Is this a common issue with superchargers on the s65? Never heard of this.

[s65e90]

Originally Posted by GIdriver

I'm kind of lost here. Excuse my ignorance but, how does this happens? Is this a common issue with superchargers on the s65? Never heard of this.

excessive crank case pressure is not a big issue on a N/A car but moreso boosted applications where the car sees positive crankcase pressures. OEM systems recirculate this blow by back into the intake system (mainly for emissions requirements). Bypassing the setup altogether or using a catch can eliminates some of the oily mess found in intake tracts/intercoolers/etc.

[exmowner]

Originally Posted by GIdriver

I'm kind of lost here. Excuse my ignorance but, how does this happens? Is this a common issue with superchargers on the s65? Never heard of this.

I had never heard of it either...

I didn't like the fact that oil was getting into the intake filter.

I traced the root to this hose (see arrow). It seems to come from behind the plenum.

From the pictures I found on another form I realized it's possible to reuse the fittings to tap the catch can into.

[JFWM3]

Originally Posted by GIdriver

I'm kind of lost here. Excuse my ignorance but, how does this happens? Is this a common issue with superchargers on the s65? Never heard of this.

I'm a little lost on this one too. I wouldn't mind if Roman from ESS or one of the other FI suppliers would chime in. ESS did a lot of testing, and if it was problematic I am sure that they would have come up with something. And FI is used on a lot of OE applications without excessive oil in the intake system.

With excessive oil in the intake system, the catch can approach could be treating the symptom as opposed to the disease. In other words, is there something else causing excessive oil in the intake system, is it a high mileage car with the valve guides starting to wear, or rings etc. causing the issue.

Can a FI kit supplier chime in?

[Beedub]

different platform but heres my boosted z4m with the ultimate catch can from 42DD..
its an awesome piece of kit..... it even has its own dipstick!! inside it has 4 perforated SS mediums..... some vapour will always find its way but this thing catches alot of it!! very pleased and it fits in nicely too with lots of options for keeping it low key.

[exmowner]

Originally Posted by JFWM3

I'm a little lost on this one too. I wouldn't mind if Roman from ESS or one of the other FI suppliers would chime in. ESS did a lot of testing, and if it was problematic I am sure that they would have come up with something. And FI is used on a lot of OE applications without excessive oil in the intake system.

With excessive oil in the intake system, the catch can approach could be treating the symptom as opposed to the disease. In other words, is there something else causing excessive oil in the intake system, is it a high mileage car with the valve guides starting to wear, or rings etc. causing the issue.

Can a FI kit supplier chime in?

My car has 16000miles

[exmowner]

Originally Posted by Beedub

different platform but heres my boosted z4m with the ultimate catch can from 42DD..
its an awesome piece of kit..... it even has its own dipstick!! inside it has 4 perforated SS mediums..... some vapour will always find its way but this thing catches alot of it!! very pleased and it fits in nicely too with lots of options for keeping it low key.

Thanks! It looks like it was part of the kit.

PS> your engine bay is clean