AOS replacement tips

[liifesfun]

There seems to many references to AOS replacement and varying opinion on the degree of difficulty.

One thing I think can be said, its not an easy job, even with instructions and should be regarded as difficult but do-able and I can see its a 2-5 hour job (suspect a hoist makes it much easier)

A lot of threads lead to BF instructions which are rather simplistic but thats understandable given its hard to get pictures of all the parts and where they live and hence its a messy and awkward job. I think a key is to study the new AOS noting all the connections and size so that you have a picture in your mind as to where relatively you will find the clamps and bolts as you will work from the top and bottom of the car and at first not know where all the related parts are.

One thing I found differing from the instructions, was that the middle tube doesnt have to be disconnected prior to removing the AOS its easier to pull the AOS partly out and then remove this hose as there is some slack and its, of in a second (not sure if being a TIP and Australian delivered makes any difference, extra plumbing?, but I must have played for 1/2 hour trying to get it out insitu.)

I agree on cutting the bellows, the new AOS has them on it, in fact you may not need to cut the bellows, give it a good tug and see if it rips (ie its rotten) and then take the clamp off from the top after the AOS is removed.

I did the worm drive clamp replacement BUT would like to know if anyone has a good trick to refitting the belows, I found there is little room and as you are working blind with one hand virtually hidden from site its a matter of feeling your way around and pulling it over the joining pipe, even with the clamp sitting loosely over the bellows its was unbelievable, I ended undoing the clamp so it came out of the worm dive after removing it. Once I had the bellows (like pulling on a boot) on it, I "'threaded" the clamp around the belows and back into the worm drive (which isnt that easy either) . I have thought about it since and wondered if your blue tacked the clamp to the top of the belows against the AOS, maybe is the trick whilst you fit the rubber bellows tube. You could then slide the clamp down into position. One benefit of the worm clamp is that its easy to spot and hence locate the bellows to check that have seated right afterwards, you can see with a torch from underneath without jacking the car.

That all said, REALLY pleased its done, Car idles perfectly, doesnt smoke, whiffy smell is gone, discovered that was the oil leak source (bellows had a slight split I think) and starts like new. PS Loren, from 6 months ago, thats was the final part of the idle issue (post MAF replacement, ICV clean, throttle body clean), once again THANKS to this site, the car is running beautifully and I know a lot more about it which makes for more enjoyable driving

So now I have a car I proud to drive again, dont have to wait to everyone has gone to start it, LOL, saved a bundle of money (minus the physio bill and skun knuckles medical treatment), sorry dont have pictures that I wanted to take as my hands were that filthy it was 33c and too hot for gloves.

Hope this helps someone and interested if others have the tips for the clamp and belows fitting.

Here endeth my therapy.

Bruce

[juniinc]

It isn't easy! good job Bruce. So what was the longest waiting time? LOL

There seems to many references to AOS replacement and varying opinion on the degree of difficulty.

One thing I think can be said, its not an easy job, even with instructions and should be regarded as difficult but do-able and I can see its a 2-5 hour job (suspect a hoist makes it much easier)

A lot of threads lead to BF instructions which are rather simplistic but thats understandable given its hard to get pictures of all the parts and where they live and hence its a messy and awkward job. I think a key is to study the new AOS noting all the connections and size so that you have a picture in your mind as to where relatively you will find the clamps and bolts as you will work from the top and bottom of the car and at first not know where all the related parts are.

One thing I found differing from the instructions, was that the middle tube doesnt have to be disconnected prior to removing the AOS its easier to pull the AOS partly out and then remove this hose as there is some slack and its, of in a second (not sure if being a TIP and Australian delivered makes any difference, extra plumbing?, but I must have played for 1/2 hour trying to get it out insitu.)

I agree on cutting the bellows, the new AOS has them on it, in fact you may not need to cut the bellows, give it a good tug and see if it rips (ie its rotten) and then take the clamp off from the top after the AOS is removed.

I did the worm drive clamp replacement BUT would like to know if anyone has a good trick to refitting the belows, I found there is little room and as you are working blind with one hand virtually hidden from site its a matter of feeling your way around and pulling it over the joining pipe, even with the clamp sitting loosely over the bellows its was unbelievable, I ended undoing the clamp so it came out of the worm dive after removing it. Once I had the bellows (like pulling on a boot) on it, I "'threaded" the clamp around the belows and back into the worm drive (which isnt that easy either) . I have thought about it since and wondered if your blue tacked the clamp to the top of the belows against the AOS, maybe is the trick whilst you fit the rubber bellows tube. You could then slide the clamp down into position. One benefit of the worm clamp is that its easy to spot and hence locate the bellows to check that have seated right afterwards, you can see with a torch from underneath without jacking the car.

That all said, REALLY pleased its done, Car idles perfectly, doesnt smoke, whiffy smell is gone, discovered that was the oil leak source (bellows had a slight split I think) and starts like new. PS Loren, from 6 months ago, thats was the final part of the idle issue (post MAF replacement, ICV clean, throttle body clean), once again THANKS to this site, the car is running beautifully and I know a lot more about it which makes for more enjoyable driving

So now I have a car I proud to drive again, dont have to wait to everyone has gone to start it, LOL, saved a bundle of money (minus the physio bill and skun knuckles medical treatment), sorry dont have pictures that I wanted to take as my hands were that filthy it was 33c and too hot for gloves.

Hope this helps someone and interested if others have the tips for the clamp and belows fitting.

Here endeth my therapy.

Bruce

[Tool Pants]

There is a spring band clamp that comes with a plastic blue thing that compresses the clamp so that the clamp is open. When the clamp is in position the blue thing is pulled away and the clamp closes. I have seen the mechanics use it so I took a picture.

[Cassiebox]

Bruce-

Good job. Agree, it certainly isn't as easy as changing the cabin filter ;)

Not sure when you cleaned the TB last but if your AOS was really bad and you had a fair amount of oil in the j-tube, you'll probably benefit from cleaning it again.... JM2C

Good tips - thanks for sharing.

[Stefan]

I highly recommend using a spring clamp tool. It makes the job much easier. Then there is no need to cut the bellows. Here's the one I got (for $10):

"Craftsman Swivel Jaw Hose Plier"

http://www.sears.com/shc/s/p_10153_12605_0...05&sLevel=0

I also advise against replacing the spring clamp with a screw type one. The spring clamp automatically has the right tension and with the above tool it is pretty easy to put in place.

[JP-"S"]

PLEASE PLEASE PLEASE listen. I DYI'd the AOS last year and did not change the bottom tube because I was told it was always the top the had the issue. Recently the car had been dumping oil on the ground. I just had a friend of mine who is a Porsche cup car mech. dig into it to find the root of the issue. After removing a ton of oil from the engine compartment we found the bottom tube had cracked and split and was indeed the issue in question. So if you do do the AOS PLEASE change that piece also. Trust me otherwise you will not drive the car and the drop another grand into finding what the problem is.

__________________

[Stefan]

I agree completly. Nowadays, they seem to always sell the AOS with the bottom rubber tube. But it's worth asking them to be sure. If not, the part is very cheap anyway.

[Cassiebox]

I agree completly. Nowadays, they seem to always sell the AOS with the bottom rubber tube. But it's worth asking them to be sure. If not, the part is very cheap anyway.

correct Stefan - per what I was told by sunset - revision .04 comes w/ the bellows

[JP-"S"]

I agree completly. Nowadays, they seem to always sell the AOS with the bottom rubber tube. But it's worth asking them to be sure. If not, the part is very cheap anyway.

correct Stefan - per what I was told by sunset - revision .04 comes w/ the bellows

Nope...Just purchased last week 118 bucks for the AOS and $65 for the newest version of the lower Bellow tube.

[liifesfun]

It isn't easy! good job Bruce. So what was the longest waiting time? LOL

Juniinc

All I am prepared to say is that the smoke was enough that I discovered, you cant fit much camping gear into a Boxster ....... LOL

Bruce

[Stefan]

Nope...Just purchased last week 118 bucks for the AOS and $65 for the newest version of the lower Bellow tube.

We must be talking about two different things. I just bought an extra bellows tube (part # 996.107.237.52) for $13.

Part # 10 in this picture

Looks like this

[Cassiebox]

Nope...Just purchased last week 118 bucks for the AOS and $65 for the newest version of the lower Bellow tube.

Yikes! For future reference, you might want to price things out w/ Sunset Imports. Back in July, I bought the newest version AOS (p/n 996-107-023-04 which includes bellows) for $76.50 from them. Shipping was just $7.50 to PA....

[JP-"S"]

Part is the number 4 in pic.

I agree last year when I did the AOS I went through Sunset, but this time the car was at the shop and in pcs.

Edited December 10, 2007 by JP-"S"

[Tool Pants]

When you buy the oil separator it comes with the bellows.

In the parts diagram above you see the separator is #1. There is a line below the 1 and the numbers #2, #10, and #11. That means if your order part #1 then it also comes with parts #2, #10, and #11. #10 is the bellows and #11 is the upper clamp for the bellows.

The J-tube is a separate item.

[pomocanthus]

Bruce, Toolpants, JP, Stefan,

I decided to do AOS R&R myself and am stuck at step #2 (I managed to remove the J tube connecting the AOS to TB) :lol: I looked at detailed instruction from Mike Focke website where he recommends lifting and removing passenger rear tire to access the two 10mm bolts. The bolts and bellows should be visible when looking through the wheel well. I have a '99 tip and it must be different because I cannot see the AOS through the wheel well. It seems like I can get at the two bolts from above the car (through normal engine access bay) using a flex extension. Working from above the car, I can feel the bellows underneath the AOS (but cannot see it). I think I can remove it using a clamp hose pliers but I wonder how I would be able to connect the bellows on the new AOS. Also the hose (#4 in diagram above) is hidden under two bundles of wiring that I cannot move. Bruce said that it can be disconnected after removing the two bolts and pulling the AOS partly out. JP mentioned that this hose should be replaced. It seems pretty difficult to replace this hose. Any hints? Thanks in advanced for all your help. This DIY stuff is fun, frustrating, dirty, back breaking, but mostly rewarding. At the moment it is mostly frustrating :cursing:

thanks,

Hung

Edited December 29, 2007 by pomocanthus

[Stefan]

If you remove the right rear wheel you still cannot see the lower AOS bellows. But you can see part of the plastic of the AOS unit and you can also see the bolts that hold the AOS in place. You should be able to fairly easily reach them with a socket.

To connect the bellows using the clamp pliers, you compress the lower clamp and put it around the lower bellows. From above you wiggle the AOS down into approximate correct position. Then go under the car through the wheel well and use your hand to put the lower bellows on the metal tube. You can verify that it is in place by using a little mirror and a light. Then release the pliers. The rest of the connections (the bolts and the other hoses) are relatively easy. The bolts can be put back from below and all of the rest of the connections can be done from above.

If you PM me your e-mail address I can send you some pictures. For some reason, my router crashes whenever I try to upload pictures to Renntech or any other pictures site.

[liifesfun]

Hung, Stefan

Sorry to hear your grief.

My experience is the same as Stefans , the two bolts can be reached from the top, from memory I used a mini socket set with a universal joint on a mini tool bar and manged to then screw them out with my fingers. Not sure if Americans use the same term , "universal joint", its a knuckle like joint you can get for socket sets.

The bellows on the Australian (USA model ??) model can be seen from underneath but its very narrow view and you need to look underneath from about the the corner of the rear bumper (rear of the car not level with the axle) and you can shine a torch through a narrow gap but you need to know what your looking at (you can see the bottom of the belows), I only discovered once I had fitted it, thus verifying how difficult it is too see. (I think you'll find its closer to the front of the car than you expect

If Stefans photos dont arrive let me know.

If you have skype you can try me, send me a private email ,I'll give you my contact details, happy to talk on the phone.

Happy Xmas and New Year to you both

Bruce

Bruce, Toolpants, JP, Stefan,

I decided to do AOS R&R myself and am stuck at step #2 (I managed to remove the J tube connecting the AOS to TB) :lol: I looked at detailed instruction from Mike Focke website where he recommends lifting and removing passenger rear tire to access the two 10mm bolts. The bolts and bellows should be visible when looking through the wheel well. I have a '99 tip and it must be different because I cannot see the AOS through the wheel well. It seems like I can get at the two bolts from above the car (through normal engine access bay) using a flex extension. Working from above the car, I can feel the bellows underneath the AOS (but cannot see it). I think I can remove it using a clamp hose pliers but I wonder how I would be able to connect the bellows on the new AOS. Also the hose (#4 in diagram above) is hidden under two bundles of wiring that I cannot move. Bruce said that it can be disconnected after removing the two bolts and pulling the AOS partly out. JP mentioned that this hose should be replaced. It seems pretty difficult to replace this hose. Any hints? Thanks in advanced for all your help. This DIY stuff is fun, frustrating, dirty, back breaking, but mostly rewarding. At the moment it is mostly frustrating :cursing:

thanks,

Hung

[liifesfun]

Hung, Stefan

The bellow tube you can see in the attached photo (note the hose clamp on the bottom of the tube)

Bruce

If you remove the right rear wheel you still cannot see the lower AOS bellows. But you can see part of the plastic of the AOS unit and you can also see the bolts that hold the AOS in place. You should be able to fairly easily reach them with a socket.

To connect the bellows using the clamp pliers, you compress the lower clamp and put it around the lower bellows. From above you wiggle the AOS down into approximate correct position. Then go under the car through the wheel well and use your hand to put the lower bellows on the metal tube. You can verify that it is in place by using a little mirror and a light. Then release the pliers. The rest of the connections (the bolts and the other hoses) are relatively easy. The bolts can be put back from below and all of the rest of the connections can be done from above.

If you PM me your e-mail address I can send you some pictures. For some reason, my router crashes whenever I try to upload pictures to Renntech or any other pictures site.

boxster_aos_bellows_location.htm

[pomocanthus]

Hung, Stefan

The bellow tube you can see in the attached photo (note the hose clamp on the bottom of the tube)

Bruce

Bruce & Stefan,

It has gotten dark here and I've given up for the day. I will resume in the morning with your picture. I will keep everyone posted.

Thanks for such quick responses,

Hung

[Stefan]

I have sent Hung some pictures. He is welcome to post them.

[pomocanthus]

I have sent Hung some pictures. He is welcome to post them.

Here is what Stefan sent me. I think it will be helpful to others as well ...

[Picture 1 is a] picture of a failed attempt when I tried bolting the AOS before putting on the bellows. I couldn't get the bellows to go on correctly. In this picture you can see how the AOS bolts in (2 bolts just under the joint of the mirror).

[Picture 2 is of the] AOS properly installed. You cannot see this through the wheel well without a mirror. I held the camera out to ensure that it was installed properly.

[pomocanthus]

Here is more from Stefan ...

In this shot, the right rear wheel is off and the camera is actually outside of the wheel well. I have circled the lower AOS bolt. The upper one is a couple of inches above that, just barely out of sight from this picture.

Here are both bolts, closer. You can just barely see the lower bellows in the upper right of this picture.

[pomocanthus]

I'm finally done with my AOS R&R adventure. Many thanks to Stefan, Bruce and others for the direct (e-mails) and indirect (old posts) help. Once Stefan pointed out where to look for the bellows, it was just a matter of patience. Here are some observations I made.

1. removing the J-hose is pretty straight forward but reinstalling new hose took some muscle. The J or hook end that connects to the throttle body is difficult to push into place. There is not much to grab onto. Make sure the connector snaps into place.

2. removing and installing the two 10mm bolts; This is a blind operation. Once you have the car lifted and rear tire off, sit in front of the disc brake as if you're going to bear hug it and reach with your left arm into the opening shown in Stefan's pix. Feel your way around. I always felt for the bellows first as it is the most distinguishing feature. Then use your new AOS as a visual reference to feel your way to the bolts. I didn't have much success with using a wobble or universal joint to help align the socket with the bolts (as mentioned Bruce). I used a short 10mm socket with a stubby ratcheting wrench.

3. removing the hose clamps and releasing the old bellows; a cable operated hose clamp pliers from Sears ( Sears item# 00947390000) helped tremendously. The head on these pliers are a bit large and it was difficult to get it aligned just right to engage the hose clamp but it can be done. It took me a good 1/2 hour of trying. I highly recommend having a helper to squeeze the pliers and lock them while you use both hands to align with the hose clamps.

4. dislodging the AOS; I had to disconnect the oil filler hose that runs across the top of the AOS. Then the trick is to pull the AOS straight up and at the same time lean top of it toward the throttle body. Think of it as pulling up and rotating the AOS toward the driver side rear wheel.

5. disconnecting the middle hose; As someone noted, it is easier to disconnect the middle hose after dislodging the AOS. This hose is flexible and can be moved around quite a bit even when connected.

6. installing the lower hose clamp over the new bellows; similar comments as #3. A helper will makes things immensely easier as you push the bellows down on the metal tube. I didn't have a helper and by some stroke of Divine Intervention, I managed to force the bellows onto the metal tube and at the same time inadvertently releasing the hose clamp. Be careful because a releasing hose clamp can do some damage to your fingers.

7. reconnecting the middle hose; I found it easier to connect this hose AFTER the new AOS is in place but before reinstalling the 10mm bolts.

After all this my car still isn't running optimally, but it is running better with less smoke. Now I have to chase down an air leak or clog in the secondary air system. Thanks again to Stefan and Bruce for their help.

Edited January 4, 2008 by pomocanthus

[Stefan]

Bravo!

I can assure you that this job gets significantly easier in subsequent tries so be sure to lend a hand to any local Boxster owners who need this done.

Since you were having AOS problems you might want to pull one of your spark plugs and check for fouling. That can happen if the AOS dumps enough oil into the air intake.

[pomocanthus]

Will do. Thanks again for all your help Stefan.