997.2 3.6l AOS (Air Oil / Oil Mist Separator) DIY
04-13-2017, 09:32 PM
#18
Burning Brakes
Thread Starter
I "think" there was a change in both (seemed a little smoother) but I am always hyper aware of the potential for placebo effect. So for me it is more about having a revised part which hopefully means improvements were made from the original, and one which should last for many years.
Regarding the part revision; I still suspect the new part may be designed to operate at higher vacuum, but this is yet to be proven (see thread here - https://rennlist.com/forums/997-foru...-resource.html
)
I think Master provided some great insight in his post. I also think the membrane like any similar part will lose it's properties (particularly flexibility) over time and not just based on miles. If you don't mind a bit of DIY, this is a great project for a rainy afternoon or evening, and a very cheap update.
01-20-2020, 10:33 AM
#20
@EMC2 thanks for the great write up. I just did this yesterday. Other then the oil weeping at the driver side plenum rubber seal causing the metal to fuse to the rubber, everything came apart without much effort or trouble. Going back together was a pain in the ***. Those half moon clamps are a bear to get on and get seated. An hour or so of mangling my arms through tight places with sharp edges and they were back on and fully seated. The service manual says to lower the engine 15mm for better access and I think if I did this again I would do just that. For anyone else looking to do this I have pasted the torque specs for the fasteners below. Thanks
Jeff
Throttle body housing to resonance tube (aka plenum): 10 Nm (7.5 ftlb.)
Oil separator 1(AOS) to bracket for oil/water heat exchanger: 13 Nm (9.5 ftlb.)
Clamp for resonance tube (service manual say sto always replace but I re-used): 4.5 Nm (3.5 ftlb.)
Engine carrier to engine mounting (if you lowered the engine by loosening these two bolts): 85 Nm (63 ftlb.)
Cable duct to intake-air distributor (behind the plenum as shown in EMC2's pictures above): 13 Nm (9.5 ftlb.)
Jeff
Throttle body housing to resonance tube (aka plenum): 10 Nm (7.5 ftlb.)
Oil separator 1(AOS) to bracket for oil/water heat exchanger: 13 Nm (9.5 ftlb.)
Clamp for resonance tube (service manual say sto always replace but I re-used): 4.5 Nm (3.5 ftlb.)
Engine carrier to engine mounting (if you lowered the engine by loosening these two bolts): 85 Nm (63 ftlb.)
Cable duct to intake-air distributor (behind the plenum as shown in EMC2's pictures above): 13 Nm (9.5 ftlb.)
01-20-2020, 09:00 PM
#21
Burning Brakes
Thread Starter
Originally Posted by jbaker136
@EMC2 thanks for the great write up. I just did this yesterday. Other then the oil weeping at the driver side plenum rubber seal causing the metal to fuse to the rubber, everything came apart without much effort or trouble. Going back together was a pain in the ***. Those half moon clamps are a bear to get on and get seated. An hour or so of mangling my arms through tight places with sharp edges and they were back on and fully seated. The service manual says to lower the engine 15mm for better access and I think if I did this again I would do just that. For anyone else looking to do this I have pasted the torque specs for the fasteners below. Thanks
Jeff
Throttle body housing to resonance tube (aka plenum): 10 Nm (7.5 ftlb.)
Oil separator 1(AOS) to bracket for oil/water heat exchanger: 13 Nm (9.5 ftlb.)
Clamp for resonance tube (service manual say sto always replace but I re-used): 4.5 Nm (3.5 ftlb.)
Engine carrier to engine mounting (if you lowered the engine by loosening these two bolts): 85 Nm (63 ftlb.)
Cable duct to intake-air distributor (behind the plenum as shown in EMC2's pictures above): 13 Nm (9.5 ftlb.)
Jeff
Throttle body housing to resonance tube (aka plenum): 10 Nm (7.5 ftlb.)
Oil separator 1(AOS) to bracket for oil/water heat exchanger: 13 Nm (9.5 ftlb.)
Clamp for resonance tube (service manual say sto always replace but I re-used): 4.5 Nm (3.5 ftlb.)
Engine carrier to engine mounting (if you lowered the engine by loosening these two bolts): 85 Nm (63 ftlb.)
Cable duct to intake-air distributor (behind the plenum as shown in EMC2's pictures above): 13 Nm (9.5 ftlb.)
Did you happen to measure the oil filler neck vacuum before and/or after?
06-01-2022, 05:29 PM
#22
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Necro bump on this thread to see if anyone who, like Emc2, couldn't get the left AOS connector 100% seated ever had any issues stemming from it? I just preemptively swapped my AOS two days ago and could also not get the left connector 100% seated. My guess is the AOS was originally installed at the factory while the engine was out of the car as I'm not sure how one could get enough leverage to push it down all the way otherwise. I wasn't about to use a pry bar for fear of damaging the AOS or prying against the roof of my trunk.
The plenum half moon clamps were a pain, like others mentioned, and my vent tube cracked. Other than that, not horrible. I did lower the engine a bit as others mentioned to get some extra room. It's super easy to do, especially if you've ever changed your motor mounts before, and I'm not really sure how you could swap the AOS or remove the plenum without doing so.
Thx
The plenum half moon clamps were a pain, like others mentioned, and my vent tube cracked. Other than that, not horrible. I did lower the engine a bit as others mentioned to get some extra room. It's super easy to do, especially if you've ever changed your motor mounts before, and I'm not really sure how you could swap the AOS or remove the plenum without doing so.
Thx
06-03-2022, 07:29 AM
#25
Instructor
Did exactly the same and had the same impressions...
Removal is quite easy, re-seating of more complex and I am not even sure if it is 100% good on my case... hoping.
What i did I scew the AOS until screws just touch the AOS then wiggle it by hand while pushing it in place, tight screws a bit, wiggle and push, tight screws.... until I kind of felt it was in place.
For the rubber of manifold and half moons it was more than an hour of pain in the but trying to get everyting into place but think I did...
Removal is quite easy, re-seating of more complex and I am not even sure if it is 100% good on my case... hoping.
What i did I scew the AOS until screws just touch the AOS then wiggle it by hand while pushing it in place, tight screws a bit, wiggle and push, tight screws.... until I kind of felt it was in place.
For the rubber of manifold and half moons it was more than an hour of pain in the but trying to get everyting into place but think I did...
06-03-2022, 09:17 AM
#26
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Did exactly the same and had the same impressions...
Removal is quite easy, re-seating of more complex and I am not even sure if it is 100% good on my case... hoping.
What i did I scew the AOS until screws just touch the AOS then wiggle it by hand while pushing it in place, tight screws a bit, wiggle and push, tight screws.... until I kind of felt it was in place.
For the rubber of manifold and half moons it was more than an hour of pain in the but trying to get everyting into place but think I did...
Removal is quite easy, re-seating of more complex and I am not even sure if it is 100% good on my case... hoping.
What i did I scew the AOS until screws just touch the AOS then wiggle it by hand while pushing it in place, tight screws a bit, wiggle and push, tight screws.... until I kind of felt it was in place.
For the rubber of manifold and half moons it was more than an hour of pain in the but trying to get everyting into place but think I did...
To those attempting this, along with everything else mentioned here, definitely pick up a mechanic's mirror if you don't already have one. You will need it to ensure the half moon clamps are properly seated. Also helps with the AOS, though that one is a bit easier to tell when it's seated.