Crankcase ventilation/Oil Separator Mod - PeachParts Mercedes-Benz Forum

#1 09-01-2006, 12:04 AM

I got a free air line water/oil separator from work. The bowl has a small crack and hissed with the 160psi line pressure. It works with centrifugal force and a porous plastic filter.

So far it's working pretty well. After a hard run to get the engine hot, it no longer looks like I have a steam engine under my car. The exit is still vented to the atmosphere until I'm satisfied the system works. The air cleaner and u-tube are from a 79 300SD (The reason for the lack of an CCV port in the lid and the plug in the u-tube.)

It's already gathered a few drops worth of oil, but it's only been on for 30 miles.

bgkast · #2 09-01-2006, 12:51 AM

Cool. What do they cost for us people with-out such job perks and where can we get one?

Did you just have the hose venting to the atmosphere before you put it on?

Johnhef · #3 09-01-2006, 12:54 AM

Where do you have your drip tube attached to?

edit: duh same spot as mine.. for some reason I was thinking you had a 116 SD engine

#4 09-01-2006, 01:05 AM

Quote:

Originally Posted by bgkast

Cool. What do they cost for us people with-out such job perks and where can we get one?

Did you just have the hose venting to the atmosphere before you put it on?

In the $60-100 range depending on size and brand.
Yes, it was the same as now, just no separator.

Quote:

Originally Posted by Johnhef

Where do you have your drip tube attached to?

edit: duh same spot as mine.. for some reason I was thinking you had a 116 SD engine

Actually, I have the drip tube going into a pepsi bottle sitting in the old A/C receiver/dryer hole.

I just want to see how much oil it removes and how well it drains. (And it's a 300SD/300TD combo engine, BTW.

)

PanzerSD · #5 09-01-2006, 01:08 AM

By the looks of your Oil cap you got some good blowby happeing!

but the Oil separator idea is pretty ingenious! I'll have to try that!
I HATE how oil seeps from my aircleaner and fouls my nice clean turbocharger!

bgkast · #6 09-01-2006, 01:16 AM

Spendy. Next time you find a cracked one send it my way.

Admiral Ahani · #7 09-01-2006, 04:22 AM

I've been looking high and low for a used 240D oil separator to no avail. I'll try finding one of these now!

Johnhef · #8 09-01-2006, 08:27 AM

I used a 240D oil seperator on mine, works great

Diesel Giant · #9 09-01-2006, 08:30 AM

The can in the stock air cleaner is an oil/vapor seperator. The vapor is drawn into the intake and the oil condenses out of the vapor and runs back down into the oil pan. Well that is what is supposed to happen. Not having it done in the air cleaner will prevent oil residue problems.

#10 09-01-2006, 09:47 AM

Quote:

Originally Posted by Got_The_Benz

By the looks of your Oil cap you got some good blowby happeing!

I solved that by cutting a new gasket and installing it on top of the existing gasket. The original gasket seems to just dry out and leak. I should just order a new one sometime:

http://catalog.eautopartscatalog.com/mercedesshop/sophio/quote.jsp?clientid=catalog.mercedesshop&cookieid=1CQ0J3JZ41VY0KXEPH&baseurl=http://catalog.peachparts.com/&partner=mercedesshop&year=1982&product=A6150-64628&application=000001211

BioBens · #11 09-01-2006, 10:28 AM

[QUOTE=Got_The_Benz;1263894]By the looks of your Oil cap you got some good blowby happeing!

Oil seeping from the filler cap's an indicator of blowby?

#12 09-01-2006, 10:35 AM

Quote:

Originally Posted by BioBens

Oil seeping from the filler cap's an indicator of blowby?

Usually its just an indicator of a worn out cap gasket, or possibly a restriction in the vent line. All engines have some blowby, it should vent through the vent line, and the cap should be more or less leak tight.

#13 09-01-2006, 07:22 PM

Quote:

Originally Posted by BioBens

Oil seeping from the filler cap's an indicator of blowby?

Not really. Just a leaky seal. I wiped it off and put some new wheel bearing grease on it today. That should last for the next few oil changes. Doing the cap dance test makes a little jiggling with the breather plugged.

I'd be all over a 240D oil separator, if I could find one. Unfortunately my 80 was too early to have one as stock equipment.

The stock setup inside the aircleaner works OK, but I'd prefer my intake air to be oil free. When the VNT gets installed I want it to stay clean.

aklim · #14 09-02-2006, 09:52 AM

On the Ford Powerstroke boards, it is common for us to vent it or have it plumbed into the rear section of the exhaust pipe to create some sort of vacuum to suck the fumes out.

retmil46 · #15 09-02-2006, 01:31 PM

I use a Mann and Hummel Provent 200 on both my '05 Jeep Liberty CRD and '87 300D Turbo. Designed to handle the CCV on up to a 500 hp diesel and 200 liters/minute of air flow. Distributor said that on the size engine I was putting them on, it'd be upwards of 2 years or more before I'd have to worry about changing the filter element.

When I picked up the '87 with 132K on it, it was obvious that the intake had never been cleaned out. So much oil had leaked out of the boot on the suction side of the turbo, and ran down the side of the engine, that at first glance I thought the turbo drain seals had gone south. Nearly 1/4" thick oil and gunk all thru the intake. Overboost sensor and ALDA ports were completely stopped up.

Cleaned out the intake, ALDA, and all the plastic lines, and installed a Provent. Like a totally new car, will take off and run like a scalded ape now.