Weistec Oil/Air Separator: Winter Driving
02-14-2016, 11:47 AM
#1
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Weistec Oil/Air Separator: Winter Driving
On a hunch I checked my Weistec oil/air separator this morning. I drove maybe 1,500 winter miles since the last check. To my surprise, the can was almost full with gunk. It was mostly water, and a good amount of oil sludge as well.
Lesson to self: In winter driving where the engine is often cold, those cans catch a lot of condensate and need to be checked more often.
Lesson to self: In winter driving where the engine is often cold, those cans catch a lot of condensate and need to be checked more often.
02-14-2016, 11:51 AM
#2
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It fills up with condensation quickly and can also freeze blocking the PCV air flow which can end up popping the oil cap off causing a huge mess.
Not my personal experience but it has happened to someone.
Not my personal experience but it has happened to someone.
02-14-2016, 03:07 PM
#4
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On a hunch I checked my Weistec oil/air separator this morning. I drove maybe 1,500 winter miles since the last check. To my surprise, the can was almost full with gunk. It was mostly water, and a good amount of oil sludge as well.
Lesson to self: In winter driving where the engine is often cold, those cans catch a lot of condensate and need to be checked more often.
Lesson to self: In winter driving where the engine is often cold, those cans catch a lot of condensate and need to be checked more often.
02-14-2016, 06:32 PM
#5
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M156 Has a lot of blowby. The AOS is a must for any serious M156 Tuner IMHO.
02-14-2016, 06:44 PM
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2012 P31 C63 Coupe Trackrat, 2019 GLE63S Coupe Beast
Some of these engines are tighter than others. I have 27k miles and have almost no blow-by. And I drive hard. Still a must-do mod IMO.
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02-14-2016, 07:25 PM
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I knew that was coming haha
02-14-2016, 07:42 PM
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2012 C63;1971 280SE 3.5(Sold);2023 EQS 450 SUV 4 Matic (Wife's)
Good you thought to check your catch can when you did. That is a full bowl full. Would be nasty to suck that into the intake....yuk
02-14-2016, 11:51 PM
#12
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The sheer build quality of the AOS is amazing as well. I admire good engineering.
02-15-2016, 12:46 AM
#14
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I can't imagine it would be difficult. I have no experience on the M156 motors, but, back on my GTI (2.0 Turbo), it was quite easy to install.
I'm going to have my shop pop mine in anyways, since I'm in for servicing and I have no tools, lol.
I'm going to have my shop pop mine in anyways, since I'm in for servicing and I have no tools, lol.
02-15-2016, 12:53 PM
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But i did take a look at the instructions and it seems fairly straight forward. Its a tight fit in the W204 so you have to relocate the AOS near the front headlight. Typically in most M156 equipped engine bays, you mount the AOS near the back. If you have smaller size hands and some technical skill, it should be a worth while DIY.
02-15-2016, 01:39 PM
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2012 P31 C63 Coupe Trackrat, 2019 GLE63S Coupe Beast
The aluminum fittings that press into the head are a pain cause you have to do it by feel. If you lose that c-clip out of your fingers you're not going to see it again for awhile. It's not technically difficult, but it's a tight space so you should familiarize yourself with the diagrams, shape and size of things, as you're going to be doing most of it only by touch.
02-15-2016, 02:39 PM
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W204 C63 Coupe, W166 ML350 BlueTEC, 928GT, C5 Z06 & IS300 race cars, EQE 4Matic+ on order
Yeah... seeing as I live in Canada and drive mine year-round, that's the only reason why I stayed away from installing one. A Jasonoff pointed out, it's mostly water and I've also been told that it can freeze (or just solidify in the hoses like it has in the can itself) and clog up the PCV, which would lead to bigger problems.
02-15-2016, 03:49 PM
#18
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I did the install myself not long ago. The first time it takes a while to get the air inlet Y off. Weistec has good instructions on their website. The worst thing you can do is to drop a screw or washer into the engine inlet. That would make for a really bad day......
Not really difficult, but hard to get to and requires dexterity.
Not really difficult, but hard to get to and requires dexterity.
02-15-2016, 07:05 PM
#19
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Yeah... seeing as I live in Canada and drive mine year-round, that's the only reason why I stayed away from installing one. A Jasonoff pointed out, it's mostly water and I've also been told that it can freeze (or just solidify in the hoses like it has in the can itself) and clog up the PCV, which would lead to bigger problems.
02-17-2016, 11:58 AM
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2012 P31 C63 Coupe Trackrat, 2019 GLE63S Coupe Beast
Or put a mini K&N on it and let it drip oil all over the engine bay like the old DSM days haha
02-17-2016, 12:37 PM
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W204 C63 Coupe, W166 ML350 BlueTEC, 928GT, C5 Z06 & IS300 race cars, EQE 4Matic+ on order
Aside from having your car coated with oil and/or it being a massive fire hazard if you simply vent it out, you need some kind of vaccuum to properly pull out the moisture and oil vapours from the crank case. Atmospheric pressure is not enough to eliminate the vapours - that's why it's plumbed back to the intake where it gets sucked back in and burned.
