AOS Replacement not in a traditional way?

I have been planning to do this service as I am starting to have early symptoms of AOS failure. As with most things in life I spend a lot of time researching "why" it is done a certain way. I have been viewing the thread here: http://www.pelicanparts.com/techarti..._Separator.htm And am having a very hard time understanding if the majority of the AOS is exposed at the back underside of the engine as indicated in figure 17.. It appears the only need for top access is the hose connection indicated in figure 16.. Am I missing something? Is there NO WAY to simply somehow squeeze the easy release connection once loosening the two 13mm bolts on the engine case pulling it down a little and then loosening the connection? I'm trying to understand why this is impossible. Anyone tried this?

I don't understand the entire thing but if your car is a 996.1 I have a in the box brand new AOS I could sell for cheap.

Mine is a MkII but similar. It's impossible because the hoses don't have that much slack. BTW, don't try to remove the rear plenum before you loosen the bolts on the left intake manifold. Here's what works for me and yours should be even easier since your AOS bolts are very accessible from teh bottom. https://rennlist.com/forums/996-foru...i-aos-diy.html

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Pm me a price shipped to 37174

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Long needle nose couldn't make it up there for the easy disconnect.?

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I contemplated the same but just jack up the left rear, look up and you will understand. But in case you are successful, that will be a break through that deserves celebrations

I may do some exploring. I am also considering destructive surgical removal if I can devise a way to re-install

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You have a PM sir

Well I am continuing to think on this. I have another idea, what about disconnecting the hoses at the front of the engine where they connect and then having the ability to pull the AOS down enough to disconnect/ reconnect? Are the hoses hard or soft?

Two hard and two soft. If you lower the engine as much as it goes, you may have a chance.

So many AOS threads ,yet no long term durable solution. There must be a better product ? With an M96 on an engine stand(mine) it requires some well directed rocking,pushing and aligning to snug-up gently. My engine had a new AOS fitted by the P.O's. mechanic. He had torn the small diameter corrugated seal.That would have created a small vacuum leak that would have been very elusive to locate. I smeared a little grease over the corrugations of the replacement seal to help it slide in without damage. Easily done on a stand ,but from underneath with difficult access - ugh! Rennlisters report the "motorsports" AOS is not such an effective upgrade(except in huge price) . Some have hinted about using a different system to prevent it becoming overwhelmed and to make changing the diaphragm easier(instead of the entire AOS). BMW parts were mentioned but no write-ups of exactly what they do. THAT is what we really need ! But I am wondering if a contributory factor in overwhelming the AOS is insufficient anti-foam additive(silicone) in the engine oil and too much detergent(indirectly Calcium) ?

I have done this job and it is a royal PITA. Even dropping the engine to the cross-member still leaves very limited space and is a bleeder job (blood sweat tears and a lot of cursing). What is needed is a total re-design of this component. It is a crankcase bleeder at best with an intake port and exhaust port to the manifold, also heated by two coolant lines. What would be better is an LN Engineering retro fit to port the crankcase hole, maybe threaded, via hose to a remote AOS located somewhere easier to get at. Since it "blows" every 60,000 miles because it is made of plastic with a diaphragm heated by engine coolant and the engine itself, I think an engineering mind could come up with a more permanent remote solution much easier to replace. I would pay some fairly big $$$ to never have to do that job again.

DBj, I like your analysis -and the challenge to LN to develop something. It would be great to delete the coolant supply to the AOS -just one more thing to go(disastrously) wrong.Eventually engine heat + gravity would make it work well enough? Perhaps DT40 helps with the foam issue??

The Motorsport AOS does solve the problem it has double the volume of the stock. However it does have 2 issues one is the price and the other is the fitment. Engine needs to be out and it needs some custom fitting depending on your engine type and intake.

Jake replaced mine when he had the engine out, I think if he thought there was a better one he would have told me.

A point of curiosity - anyone know what Subaru do for an AOS upgrade & if it is relevant to our needs ? Since Subaru often have turbos, they are even more inclined to have oil-ingestion problems. I ask because the Subie-sports suppliers seem to have alternatives that look quite different to anything offered for the M96 despite the similar engine configuration.Sometimes it helps to look over the fence to find ideas? http://www.importimageracing.com/eng...separator.html

Its absolutely good to look over the fence, but without cutting one open and looking inside, are you willing to risk your shiny new rebuild on one? If you are staying on the street, use the stock one and make it a maintenance item along with the IMS bearing, if tracking just go to the MS one and be done.

In theory, the 'fix'? -would be to put one of the Subaru catch/drain cans ahead of the AOS to catch and return the bulk of the condensing oil. This would allow the AOS to function satisfactorily. Some of the race-prep & Track guys use this concept?

Pull the back "seats" and go in through the fire wall? Didn't one of the V8 conversions on here recently do that for easier access? Found it: http://ls1tech.com/forums/conversion...version-4.html