Sorry to bump an old tread, but this seem to be one of the most thorough ones I found so figured it would be a good place to post and keep everything in one spot...

I see that many people are putting really long hoses on their catch cans so they can mount it up front where it is more accessible (which makes sense, I agree) but I find it interesting that Weistec has their OCC kit crammed in the back corner of the engine, giving it super short runs from the pickup/outlet points, which I'm wondering if it was on purpose. I mean, why else would you mount the can in a PITA location like that if you had plenty of room up front and it would do the exact same thing? I'm wondering if they were concerned about the vaporized oil condensing and falling out of suspension before it hit the catch can and then building up in the hose? Of course if the hose is partially blocked there could be a restriction in crank case ventilation which means it will put pressure on seals and other fittings that weren't designed for it...

So catch can experts: is it better to keep the inlet/outlet distance as short as possible on these setups or doesn't it matter at all?

 

doesn't matter.

 

For as long as you don't pinch the hoses and end up impeding the airflow, it doesn't matter.

 

Actually, I was thinking it WOULD be a good idea to pitch the lines back slightly so the line from the crank case drains back to the block after the engine is shut off...

 

i'm planning on doing this myself when i get around to installing my catch can. looking for a junked OEM PCV valve first though as i'll need 2 valves. one for the flow through, and one for the drain back. not sure if space will permit though.

 

How did you remove the hose from the PCV valve?

 

Mira just a tight fit the outer rubber hose will slide off of the plastic fitting (has barbed ends to help it hold

 

https://mbworld.org/forums/c63-amg-w...-opinions.html

 

Just finished my catch can today I’m sure the information I’ll post has been covered before but here are some part numbers for things that I had to replace due to it being one time use, breaking, and or user error

(10) screws A0049905312

(2) manifold gaskets A1591410580

PCV valve A1560100370

4mm Connector A1162760929

IAT Sensor A6511530028

If the PCV valve in your car is original it will snap on you. Get the new one and you can get these fittings on eBay for about $80 (https://www.ebay.com/itm/Engine-Oil-...wAAOSwr05eIL7P). Use -10 or 5/8” lines and route a universal catch can to the front. This will help with a cooling effect making it that much more effective. Heat up the new PCV so you can spin the diaphragm and orientate it properly. With the eBay fittings above it will not fit behind the cramped C63 engine bay unless you reorientate the PCV.

The 4mm connector broke on me as I tried to pull apart the vacuum reservoir line from the U-vacuum hose connection beneath. I would recommend undoing right from the vacuum reservoir instead. It is attached to a nipple just beneath the reservoir (the thing that sits above the Y-pipe). It will take a lot of force because there’s vacuum pressure.

IAT sensor - I’ve read that either cleaning it or replacing it will help free up HP as the old one degrades over time. It’s cheap insurance/maintenance. Mine was brittle so I needed to get a new one.

Last few bits of advice.

Pull the wire loom at the back of the firewall (the S wavy thing) up and out from the passenger side. Just use a lot of force! This will give you SO MUCH more room to work and undo the Y-pipe. After you route the catch can on the passenger side the only way to remove the y-pipe clips is by accessing it from behind and beneath this hard plastic wire loom.

Blow out the nooks and crannies of the intake manifold before you remove it. Let the dust settle and you’ll decrease the chances of debris falling into the valves.

For reasembly, I used Vaseline on the vacuum connections and the new gaskets. Honestly a thin film worked perfectly.

Should be a no brainer but unplug your battery before to prevent any codes once you’re all done. It took me 7 hours having to clean the manifold and so I’d save this type of job for a weekend.

In the photo below I would highly highly highly recommend against what people have written before and from videos online. Removing this front bung right from the manifold will cause it to break. Instead twist and pull this vacuum hose from the black and blue check valve. It came off way easier this way and you will not find the bung/clamp/fitting piece anywhere!



Good luck!

Courtesy photo of the bay after the oil separator install:

 

You can now get fittings similar to a $600 catch can https://www.ebay.com/itm/124049691640

 

Nice! Great price as well!

 

The one thing I still question about the weistec style is if moving the check valve further from the manifold affects anything or if it should be closer to crankcase

 

Same one I bought. I can vouch for them fitting well. The rubber seals were a little large but worked with some oil.

My valve is still attached at the normal location and I had the eBay parts attached after the PCV.

 

Your check valve is in the normal location at the crankcase but now almost 6 feet of hose further from the intake manifold

 

Im happy with that since it’s all “cleaner“ air going into the manifold.

 

The shorter the hoses the less you will condense suspended material on the walls of the tube vs IN the OAS/Catch Can. Also, a warmer location for AOS/Can, and especially lines, the less likely those lines will coagulate and eventually clog (especially in colder climates). Having the AOS/Can in a low point will make condensed liquids on the walls more likely to flow back into the AOS/Can vs making its way to the intake tract.

 

Lines would have to be quite long to overcome the engine bay temp

 

Loop it outside the around the car. That should do it...

 

Blow-by gasses can easily exceed 300 degrees. Those temps drop as soon as they exit the engine. Length, path, and location, can influence function.

I was just trying to add some perspective based on my own experience designing and testing high performance crankcase venting and separation products.

 

Do you have any engineering to back it up? The hose lengths are about 36" and run along the hot side of the heat shield right above the header log.

I will re-locate my can if it's in a bad location.

 

Catch cans are already engineered with several layers of different types of filterA to accommodate for all this. At least I know mine is routed specifically through 4 layers of different filters to do it’s job. It’s not just an empty pop can.

 

Are you asking for a copy of my resume

If it's working as it should, don't do a thing. If not, making some simple changes can improve its functionality.

Depends on the unit. Some use baffles, some use media, some swirl pots, and some use vortex flow. My personal preference is vortex flow as it doesn't induce a flow restriction like baffles or media, and functions more efficiently over a much wider flow range. The unfortunate downside is a bigger hole in your wallet with though.

The premise behind the large can or Gatorade bottle is that blow-by gasses expand, cool, and suspended liquids condense in the can. It's not a bad theory, and often better than nothing, but certainly not an optimized solution.

 

No, you made a significant comment about the effectiveness of the hose length on existing solutions. It came across as it being inferior.
So it was a shìts and giggles comment?

 

I apologize on the hose comment. I think it may have been taken out of context, or maybe I should have been clearer in my commenting. I was merely trying to be informative; if anyone had interest in seeing the effectiveness of their unit, it's one of the things that can be inspected, checked, and if need be, improved upon.. The end-all being is there anything on the interior surfaces of the AOS/Can outlet hose and intake tract.

 

Hello. Did you determine which Catch Can suited the ML350?
I am hoping its a W166 Bluetec version.