Oil catch can

FastraxTurbo said:
On catch cans, it doesnt really matter what shape it is, as long as its large enough to contain the oil accumulated, and have adequate baffling to separate the oil from the gasses. The catch can HAS to be vented if both valve cover vents are routed to it without any other means of crankcase ventilation.
Click to expand...

To ad to what "that guy" said... Must be bored since he is loosing his magical skilz.. dont turn into a wizzard with only one z and now logs on.... lol

If vented... the diameter or total volume must be equal-to or greater than the amount of pressure to be released...

or in another words.. if your catch can has only 1 filter and the diameter of the inlet is only 1/2" or so (aka - go-ped airfilter)... your drinking a thirst buster with a coffee straw on a 3.0L v6

I hope that makes sense for people
 
nsxotic911 said:
A picture is worth ten thousand of my words, so here it is.. This is my current 'test' setup. Not everythign clamped down but you get the idea.

As mentioned, I'd like to:
1.) Provide filtration for the valve covers.
1.) Remove the filter because it sticks passed the bar, and even if it didn't I don't want the gases in there..
2.) Have as 'clean' of a setup..

Excuse the bad hondabond job that needs to be cleaned up around the edges..and all the other touch ups that need to be done..

Have at it...
Click to expand...

Ok, I think I see the issues. Yikes that's a tight fit. Ok, I might have some time tomorrow. I'll give you a call to discuss.
 
nsxotic911 said:
A picture is worth ten thousand of my words, so here it is.. This is my current 'test' setup. Not everythign clamped down but you get the idea.

As mentioned, I'd like to:
1.) Provide filtration for the valve covers.
1.) Remove the filter because it sticks passed the bar, and even if it didn't I don't want the gases in there..
2.) Have as 'clean' of a setup..

Excuse the bad hondabond job that needs to be cleaned up around the edges..and all the other touch ups that need to be done..

Have at it...
Click to expand...

Is there enough room to actually connect to the catch can ports or is that part of the problem? If that is part of the problem here are a few ideas I had:

1) Combine the two crankcase breather hoses with a T junction near the catch can. This should allow a very clean run of hoses that you can route the crankcase breather hoses, either above or below the throttle body. Then route the single hose to the catch can. Either use one of the catch can ports or seal both of them and tap a new hole to a more accessible location (perhaps right below). Leave the catch can breather filter where it is, or attach a hose and relocate it to a place you desire.

OR

2) Again combine the two crankcase breather hoses to a T joint near the catch can. Route that to the port hole where the existing filter is located. Seal both the existing breather ports on the catch can and then tap a new filter port below those ports. Then either mount the catch can breather filter horizontally out the side, or run a hose and route that the filter to a location you prefer. Just make sure to not let the catch can fill up and empty it out so it doesn't over flow and run out the filter.

As far as venting the catch can to the engine bay, it shouldn't be a problem. It's where I vent my catch can and most others. If the filter does its job, the vapor is going to be mostly water and shouldn't be a problem. I get a little steam to flow out of mine but it doesn't coat the glass or engine bay with anything oily or greasy.

As far as sealing the catch can ports, keep in mind, fortunately the catch can won't be under any pressure. So the seal doesn't have to be anything serious; it only needs to be liquid-tight. You can either just put a closed end cap on the end or tap it and put a washer/bolt on it or something similar.

Does this help? :smile:
 
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I had Dali's tank you have first. I eventually sold it to go with a different setup but if I were you I'd get that filter outlet reworked. Maybe just take it to a local shop and get a L AN fitting welded or something like that. That way you can attach a hose and route it anywhere you want with a larger filter.

Boost=more than stock crankcase pressure
Larger outlet=less crankcase pressure

There are some that are FI and don't run anything but stock set up I believe and there's someone I know that just has small little filters on their valve covers, but I know from my past experience that I want the most venting as possible...
 
sduffass said:
I had Dali's tank you have first. I eventually sold it to go with a different setup but if I were you I'd get that filter outlet reworked. Maybe just take it to a local shop and get a L AN fitting welded or something like that. That way you can attach a hose and route it anywhere you want with a larger filter.

Boost=more than stock crankcase pressure
Larger outlet=less crankcase pressure

There are some that are FI and don't run anything but stock set up I believe and there's someone I know that just has small little filters on their valve covers, but I know from my past experience that I want the most venting as possible...
Click to expand...

You can also use a E-Vac tube on your exhaust to generate a vacuum on your catch can and eliminate the filter to atmosphere, You have to make sure your catch can has an effective internal seperator to remove the oil from the crank case gasses prior to the connection to the exhaust. Most use some form of steel wool as a filter material in the catch can to allow the oil to collect in the tank better. With this type of system a closed catch can is most effective and will in extreem cases provide a vacuum to the crank case at high RPM's. Use of a check valve on the vac line is ussually recommended, and as this system has the potencial to draw oil from the engine keeping an eye on oil consumption is recommended.

Info on a E-Vac tube here:
http://vibrantperformance.com/catalog/index.php?cPath=1022_1070_1340

More info on catch cans and scaveng systems here:
http://moroso.com/catalog/categorydisplay.asp?catcode=18549

Dave
 
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DDozier said:
You can also use a E-Vac tube on your exhaust to generate a vacuum on your catch can and eliminate the filter to atmosphere, You have to make sure your catch can has an effective internal seperator to remove the oil from the crank case gasses prior to the connection to the exhaust. Most use some form of steel wool as a filter material in the catch can to allow the oil to collect in the tank better. With this type of system a closed catch can is most effective and will in extreem cases provide a vacuum to the crank case at high RPM's. Use of a check valve on the vac line is ussually recommended, and as this system has the potencial to draw oil from the engine keeping an eye on oil consumption is recommended.

Info on a E-Vac tube here:
http://vibrantperformance.com/catalog/index.php?cPath=1022_1070_1340

More info on catch cans and scaveng systems here:
http://moroso.com/catalog/categorydisplay.asp?catcode=18549

Dave
Click to expand...

That's a pretty cool idea! I'll read up more about it. Right now my system works I think very well. When my engine is warmed up and I'm doing pulls I see my breather tank in my rear view mirror. I'll post a vid one of these days.
 
I like the solution of removing the PCV valve and plugging up the intake manifold PCV hose inlet. Seems to follow the KISS method but still trying to understand the pros/cons here.

According to Rob Morrison (DAL Motorsports) earlier NSXs had problem with the rear valve cover spewing out oil. Blodi - it's interesting that you put the catch can in the rear and not in the front like Rob recommends.

Has anyone had this type of problem? Jon - was this an issue with the FXMD NSXs?

Rob offer's two solutions. Bryan - it seems you're employing something similar to his "Long" solution?

I have oil spewing into my intake manifold since i'm not currently using a catch can on my CTSC. I believe it's also causing my #4 vacuum line to clog up.

From the DAL website.
A lot of stock NSXs have had problems with oil spitting out of the rear valve cover under heavy tracking at high RPM. Honda acknowledged this design flaw by redesigning the rear valve cover on the later cars. Some have never experienced this... some don't drive hard enough. I have permanently solved the problem on all of the cars including our race cars. The problem- (Likely accentuated by your new driving capabilities or style) In V-tech your oil is routed to the heads (Via solenoid valve) to facilitate the hydro lock of the rockers below the more aggressive cam lobe. This design requires massive amounts of oil that leaks profusely like the oil pressure at the crank bearings. The rear head actually fills with oil (The reason why an Accusump is needed for extended V-tech and high G turns... Not enough left in the pan) When the rear cover is full, high-G right hand turns push pure oil out the tube... Not what a breather was designed for. In the OE design, minimal oil is routed directly back into the engine at the throttle body and burned. A breather can be bolted horizontally on the ledge behind the drivers head (In the engine compartment)

You have two options (One takes longer then the other)

(Short)

Plug the rear valve cover oil out

Plug the hole in the intake hose before the throttle body

Plug the vacuum line (engine side) going to the front valve cover PCV. (discard PCV)

Run a hose from the front valve cover (PCV hole) to the new catch can. Preferably as high as possible.

I promise, no one needs to re think this, it will work.

(Long-This one requires valve cove removal, but is the best solution)

Drill the side of the front valve cover (Similar location as the hole on the rear valve cover)

Remove the pressed in tube sticking out of the rear valve cover (It’s pressed in)

Tap both covers for AN fittings

Run a hose from one valve cover to the other

Plug the hole in the intake hose before the throttle body

Plug the vacuum line (engine side) going to the front valve cover PCV. (discard PCV)

Run a hose from the front valve cover (PCV hole) to the new catch can. Preferably as high as possible


Both variations would be more professional if the valve covers were removed for tapping to AN fittings. The PCV hole will require disassembly and reassembly of the internal baffle in order to use a bulk head fitting. Note- fittings can not be welded, as the valve covers are Magnesium.
Click to expand...
 
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I read previously from awhile somewhere where steel wool used to baffle isn't a good idea because I could rust and in time may start to fall apart. It makes sense though in time.

The linked tank you posted doesn't breath to the atmosphere so it would HAVE to be used with the PVC valve and your other valve linked above?
 
RYU said:
I like the solution of removing the PCV valve and plugging up the intake manifold PCV hose inlet. Seems to follow the KISS method but still trying to understand the pros/cons here.

According to Rob Morrison (DAL Motorsports) earlier NSXs had problem with the rear valve cover spewing out oil. Blodi - it's interesting that you put the catch can in the rear and not in the front like Rob recommends.

Has anyone had this type of problem? Jon - was this an issue with the FXMD NSXs?

I have oil spewing into my intake manifold since i'm not currently using a catch can on my CTSC. I believe it's also causing my #4 vacuum line to clog up.

From the DAL website.
Click to expand...

Why does it matter for the breather to be as high as possible? I though if there's pressure in a system and an outlet that pressure will be released anywhere it can.
 
sduffass said:
Why does it matter for the breather to be as high as possible? I though if there's pressure in a system and an outlet that pressure will be released anywhere it can.
Click to expand...

I was always told so the oil has a harder time to reach the catch can and drains back in the motor. The water and fuel junk can easily make it to the catch can
 
My catch can setup:

IMG_4840.jpg


IMG_4838.jpg


Basically just a reworked SOS tank that I modded. Works great.
 
^absolutely nothing. I deleted it and just have another filter there now. SOS instructions on plumbing the can has you run that line into the can, run a filter on the side, and tee off the two valve covers into one port on the can... If that makes any sense at all. But yeah... I wouldn't think it would do anything other than slightly pressurize the can under boost. As for the oil cap idea- I got the idea from seeing some B-Series turbo setups using them before. Future final plan would be to use a Jiffy tite quick disconnect fitting on the cap to ease with disassembly when doing oil changes.
 
RYU said:
I don't see a one-way valve on that line? ^^^
Click to expand...

RYU said:
If you have the small hose that leads from behind the TB into the catch can w/o a one-way valve then essentially you have a vacuum leak. Someone correct me if i'm wrong please.
Click to expand...

chudson1549 said:
That looks like you are correct
Click to expand...

Yup, that line is now a vacuum leak from the looks of it. Not sure if that is a FI car, if so, even worse.

BTW, I really like the vent off the top of the oil cap.
 
Elite said:
Yup, that line is now a vacuum leak from the looks of it. Not sure if that is a FI car, if so, even worse.

BTW, I really like the vent off the top of the oil cap.
Click to expand...

I gotta post pictures of the way I have it set up. This was taken right after I did the mods to the can and didnt have another filter to run. The line you guys are talking about isn't on there anymore and I have the barb off the throttle body plugged. The can now has three filters on it. It's pretty cool- I can actually watch the vapors escaping through the filters through my rear view mirror. The oil cap vent I feel really helps the crankcase breathe a lot better. I need to take off the other valve cover and make another port on it so both banks are "equally vented".
 
I am currently intalling a VISION oil catch tank on an NA NSX and want to know what's the best solution for me;

1:
-connect both valve cover lines with an Y-piece to the inlet of the catch can
-connect one line from the outlet of the can to the trottle body (like the original setup)
-put a filter on top of the can?

2:
-connect both valve cover lines with an Y-piece tot the inlet of the catch can
-close the nipple on the trottle body (so not connected with the can.)
- put a filter on the outlet of the can.

and what about the line that goes from the rear valve cover towards the intake tube? This was never mentioned in this topic? The front one goes to the trottle body, the rear one goes directly to the intake tube (small black metal line)

Many thanks
Tech7042 said:
I gotta post pictures of the way I have it set up. This was taken right after I did the mods to the can and didnt have another filter to run. The line you guys are talking about isn't on there anymore and I have the barb off the throttle body plugged. The can now has three filters on it. It's pretty cool- I can actually watch the vapors escaping through the filters through my rear view mirror. The oil cap vent I feel really helps the crankcase breathe a lot better. I need to take off the other valve cover and make another port on it so both banks are "equally vented".
Click to expand...
 
Wetteren-20130106-00097 (2).jpg


I took a picture to expain my problem. So its for an 3.O NSX, not FI (yet). I know I'm in the wrong subforum for NA but didn't want to start a new thread.

I have the front cover line(including pcv-valve on original place) and the rear cover line together on an Y-coupling. from there to the can. And then I'm starting to get confused:

1. Leave it like on the picture: Breather filter on top, nipple behind the trottle body/manifold covered or closed(still open on picture) and keep the pcv where it is?

2. replace the filter with a line going to the nipple behind the TB. and keep the pcv where it is?

3. combination of 1 and 2: leave the filter, and use an extra hole on the can to connect a hose between can and nipple behind TB?

4. and do I need an extra PCV valve anywhere on this line between nipple at intake manifold and catch can?

anyone please??
 

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