Oil catch can

[curtsr]

I was gonna start a thread on todays oil change and this old one was bumped.

After about 4k miles between two oil changes I drained mine today and here is the disgusting goo:

Update: After 3 days the contents had settled into 4 distinct layers:

This presents with an odor between oil and gas. Kinda expected it to smell like bongwater but it still had an automotive type smell. I mean, it looks like people tell me bongwater smells like. Oh whatever... :smile:

No volume listed on the Kerr mason jar but I'm pretty sure that it is 16oz. So call the contents 12oz but this is after two oil changes over 5K miles. So 6oz per 2k miles since I changed my oil today after just 2K miles and it was really dirty. SouceOne did my last change when he did my dual carbon clutch install and while it was up in air I asked him to do a change. He used Mobil 1 5W - 30 that change and I used it for this change also. Since my LoveFab rebuild, a change every 2K has happened but not by design.

After Brian did the clutch I drove the car back to Cody for him to install an AEM series 2. And he routed the catch can gas discharge from vented to atmosphere to the intake stream. I doubt that this contributed to the dirty condition after 2K miles but it appears that where I used to change oil every 3K, the new rule is 2K because it was that bad visually. But, at 600+ whp maybe I'll be down to 2K between rear sets too.

 

[Cody@LoveFab]

A solution that we've since introduced is a drain back to the oil pan, which will make the catch can system maintenance-free. Curt, your car should be pretty easy to convert with a couple of fittings. No more "messy" drainings.

We will be releasing several new products in the coming weeks, so stay tuned.

 

[Stephen@NCAutoUSA]

Cody, other than the maintenance issue with emptying a catch can "which btw takes a whole 2 min" is there any reason why you'd want the contents of that jar recirculated back into the engine?

I personally wouldn't want that jar back in my engine.

 

[Cody@LoveFab]

The catch can was filled by the engine, therefore, its already in your engine. With no way to escape, the vapors, oil, and sludge just accumulates there and is reacts with air and moisture which gives the false assumption that its actually "filtering". The inside of your valve covers go through the same condensation transformation during every heat cycle.

Obviously its the end-user's choice, but personally, I have enough things to worry about and prefer a simple drain back to the oil pan.

 

[curtsr]

Cody, other than the maintenance issue with emptying a catch can "which btw takes a whole 2 min" is there any reason why you'd want the contents of that jar recirculated back into the engine?

I personally wouldn't want that jar back in my engine.

Thanks for reminding me about that.

My initial thought after the contents had settled was that it is a secondary oil filter, one that clearly traps its share of contaminants.

So yes, I think that I would not want it reintroduced once filtered.

Draining every 4,000 miles really isn't a problem. My only problem is remembering which way to turn the petcock since its inverted. :redface:

A solution that we've since introduced is a drain back to the oil pan, which will make the catch can system maintenance-free. Curt, your car should be pretty easy to convert with a couple of fittings. No more "messy" drainings.

We will be releasing several new products in the coming weeks, so stay tuned.

A bigger concern to me is the smokescreen that the car throws after some spirited driving. Getting off the highway and sitting at a light for a minute when I leave the light occasionally it will leave a large blanket of smoke. Not often, and only after spirited driving- but it is kinda embarassing. Almost like it "loads up". The embarassment does go away the next time that the boost hits.

 

[Cody@LoveFab]

I wonder if the catch can was "full", essentially blocking all crankcase evacuation? Just throwing ideas out there. The randomness is odd.

 

[curtsr]

I wonder if the catch can was "full", essentially blocking all crankcase evacuation? Just throwing ideas out there. The randomness is odd.

No, I wish. It did it again literally right after the oil change/ can drain.

About 5 miles of spirited highway driving I got off at an exit. I stopped momentarily turned right and drove 4 blocks normally where I stopped at a light for about three minutes. When the light changed I pulled away and discharged a smokescreen. It was done after that and usually does stop after that.

It's like when its under boost for a period, oil gets somewhere it shouldn't be and then burns off. I don't think that it is built-up crankcase smoke but I could be wrong.

 

[Stephen@NCAutoUSA]

The catch can was filled by the engine, therefore, its already in your engine. With no way to escape, the vapors, oil, and sludge just accumulates there and is reacts with air and moisture which gives the false assumption that its actually "filtering". The inside of your valve covers go through the same condensation transformation during every heat cycle.

Obviously its the end-user's choice, but personally, I have enough things to worry about and prefer a simple drain back to the oil pan.

Yeah I hear you. I've heard before that whatever is in the catch can doesn't always equal what's inside or being circulated inside the motor. Just like how some have stated that during different seasons depending on the weather it fills up quicker than other times.

Personally I've only emptied mine a few times. Every time I check my oil level, about 1k miles I empty my catch can. I can say that when I was driving last year during the winter/colder months there was more stuff in there then when I was driving in the late spring/summer time. Not sure if there's a correlation between that or not.

I've heard of some owners draining back to the oil pan, I'm just not one of them. It takes me 2 seconds to unscrew my drain plug and for me I'd rather just be safe.

- - - Updated - - -

Curtsr.

Has your problem happened before or was it just after when you changed your previous catch can set up?

Can you post a picture of your current setup? From my understanding instead of venting to the atmosphere via filters you have a hose going into your intake?

 

[type-Rman]

I don't think you want to split the Y like that. The reason being one side is neg pressure and the other is positive pressure. One changes depending on throttle but I forget which one "it's listed in the thread somewhere broken down". Also the whole propose of a catch can is for the vapors to go pass, vent, and the baffle separate the liquor and other things and make it drop to the bottom which you can drain later. The set up you have will probably have the tendency to suck back in those vapors and things.

You need to tap the other side of your catch can and put an AN fitting in there forcing your vapors to flow through. But I'm not sure of the internal construction of your tank so it may or may not be baffled so you wouldn't want to tap and drill into the baffle itself and mess anything up.

I thought both of the covers have positive pressure? And the intake manifold negative on an ATMOSPHERIC ENGINE? Since I have no return line towards the intake manifold (I closed the nipple) It can't be any problem, or am I seeing this wrong?
And allright, it's not ideal for the moment, since it's not baffled and oil doesn't drain back to the engine, but, with the bolt underneath the can I can simply drain, and a non-FI NSX won't be throwing out that much of oil anyway. Most important for me at the moment is that it's not throwing oily gasses back to the manifold.

SO, If someone can confirm all of this?

 

[Stephen@NCAutoUSA]

Ops my bad. I was getting things mixed up. I reread some of the earlier posts and think I was getting some thing mixed up.

 

[type-Rman]

Ops my bad. I was getting things mixed up. I reread some of the earlier posts and think I was getting some thing mixed up.

No problem, really appreciate you are trying to help :smile:

So my setup will work like this?

 

[curtsr]

Updated my post with updated pic of CC residue.
When we get back OT I'll post a pic of my CC set-up.

 

[rjwong]

how does a catch can without a vent/breather filter work? IE the cusco and greedy type canisters? How would one hook up a fully enclosed catch can?

 

[SuperSonic]

So for a fi car, it seems this is recomended. What's different on mine is my front valve cover just has a filter on it while my rear bank ties back into the throttle body. Is there something wrong with this? I know Wil's turbo set up doesn't have the nipple for the 00 up air pump (not that it matters) or for the front bank valve cover, so I just put a filter on it lol. At one point I tried to connect the two valve covers into one, but that threw off the vacuum in the system. Would running a catch can even do anything? I need to check that filter since if I get in it my engine bay smokes a tiny bit from around that filter.

 

[BATMANs]

when my engine popped i needed an oil catch can.

Now that it's rebuilt i don't need it.

Same story with my service writer that has a turbod NSX when he blew the engine and after it was rebuilt.

Our thoughts are that if you need one, especially if ur normally aspirated it's very likely that something is wrong like the pistons are not sealing that well.

 

[bngl3rt]

On my car (NA) I used a ARO-Flo pneumatic filter inbetween the valve cover and PCV valve.

Bump from the dead, anyone got more ideas/resources on how to do this in the NSX?

 

[Mac Attack]

Bump from the dead, anyone got more ideas/resources on how to do this in the NSX?

Sure. On a N/A vehicle, just insert a generic air/oil separator (I use Moroso's setup with internal wire mesh) in between your PCV valve on the valve cover and the hose that goes into your air intake.

For a F/I system where you loose your traditional intake vacuum source, I use dual air/oil separators (one for each valve cover) with a venturi tube upstream of the compressor(s) for a "vacuum source" and a pancake valve for vacuum control. Or, you can use the exhaust system for the traditional hot-rod way of supplying vacuum.

Read through the Service Manual for a nice overview of the PCV system, the flow paths, and what it is doing. The PCV system is important to keep your oil clean in 90% of your driving (unless it is a track-only vehicle). Therefore, I dislike any idea of just venting it to the atmosphere since it is doing more harm than good. It's not just for emissions.

Low-tension rings and vacuum pumps are another discussion....

Dave

 

[CB72]

Sure. On a N/A vehicle, just insert a generic air/oil separator (I use Moroso's setup with internal wire mesh) in between your PCV valve on the valve cover and the hose that goes into your air intake.

For a F/I system where you loose your traditional intake vacuum source, I use dual air/oil separators (one for each valve cover) with a venturi tube upstream of the compressor(s) for a "vacuum source" and a pancake valve for vacuum control. Or, you can use the exhaust system for the traditional hot-rod way of supplying vacuum.

Read through the Service Manual for a nice overview of the PCV system, the flow paths, and what it is doing. The PCV system is important to keep your oil clean in 90% of your driving (unless it is a track-only vehicle). Therefore, I dislike any idea of just venting it to the atmosphere since it is doing more harm than good. It's not just for emissions.

Low-tension rings and vacuum pumps are another discussion....

Dave

During a recent track day at the Spa Francorchamps circuit in Belgium with my LoveFab turbocharged NSX, I discovered that oil was coming out of my crankcase breather...
The engine internals are 100% stock and I remember that before installing the turbo there was some oil in the throttle body.
There is absolutely no smoke coming out of the exhaust and no more oil appeared during the 400 km drive back home.
What's wrong with my home built crankcase breather?
Clearly there is no connection to any vacuum source as I don't quite understand how to do this with a turbo set-up?
How come the crankcase breathers on the market ( SoS , LoveFab) don't connect to a vacuum source?
Will they also let oil come out during track days?

As a side note, I was the sole NSX owner amongst maybe 80 to 100 Porsches mostly GT3's.
It's with examples like the crankcase breather that one measures how difficult it is to bridge 20 years of ongoing development the P cars have received since the NSX came out on the market.
Here's a picture of my set-up

It's r

 

[Stephen@NCAutoUSA]

Like literally oil coming out of the top of that filter?

 

[CB72]

Like literally oil coming out of the top of that filter?

Well I suppose so because I don't see where it could come from anywhere else?
In the meantime I looked into the crankcase breather and guess what...there are NO internal divider walls!
So in practice, any pressure build-up is fed directly to the tiny little filter.
I suppose that in well built breather the hot oil fumes are routed through dividers to allow the oil to condense and thus remain in the breather?

 

[DDozier]

What's wrong with my home built crankcase breather?
Clearly there is no connection to any vacuum source as I don't quite understand how to do this with a turbo set-up?
How come the crankcase breathers on the market ( SoS , LoveFab) don't connect to a vacuum source?
Will they also let oil come out during track days?

You can try and add some course steal wool to the part of the canister where the filters in connected to the canister to act as a prefilter and allow the hot oil vapors to condence on the steel wool and drip back into the canister, but the real solution is to add the steel wool and add a vacuum source in place of the filter to atmosphere. The vacuum source needs to be after the air intake filter but before the turbo. To get maximum draw on that line it is best to weld a tube in your intake pipe at a 45* angle and allow a small amount of the tube to protrude into the intake tube cut on a 45* angle.

Dave

 

[CB72]

Dave,

Many thanks for this detailed reply!
I really like the idea and I believe there is an added advantage in recirculating the oil vapors as the car will no longer smell like a hot rod...
It will also suit the LoveFab design as the air filter stands vertically and there will thus be no issue of oil residues dripping on the filter itself.
Given the volume of air going through the engine, I suppose any negative aspect of routing the blow-by gasses into the intake are negligeable?
Thanks again

John

 

[MinnesotaR6]

how does a catch can without a vent/breather filter work? IE the cusco and greedy type canisters? How would one hook up a fully enclosed catch can?

im with this guy! im thinking about purchasing a catch can WITHOUT a breather attached.

My current catch can has a filter/breather and vents the oil smell in my engine bay making my cabin smell like a race car!

 

[RYU]

Bumpity bump..

So what catch can is everyone running?

I've had 2+yrs on mine and maybe a dozen track days or so. I'm considering changing it up.

 

[Stephen@NCAutoUSA]

I haven't driven in awhile but I still run my Stmpo tank. It's still going strong.