AOS seal replacement

[WizPorsche944]

Questions for you guys..

Do I have to take anything else off to get to these ?
Do I have to drain the oil first ?
Does this job make a mess ?
If its only a dime sized oil puddle should I still do it ?

[John_AZ]

From your signature line, you should be the teacher with your experience .

If I were to do this in advance of a leaky head gasket replacement....
(I would wait awhile unless you have already done the HG)

I would remove the intake manifold because it is easier to work on.

Now would be the time to send out the injectors to www.whitchhunter or do a DIY clean from the tech info center instructions above.
Replace all the pinch OEM clamps on the big vacuum hoses with injector clamps or non perforated screw type.

Have new rubber mounts for the ICV/ISV valve and clean the valve. Replace the heater control valve if it is old and has a white deposit on the pivot. Change the small coolant tube above the heater control valve. Put a piece of tape over the TDC hole on the bell housing.

Regap the sensors. Clean the grounds on the bell housing. Put a piece of tape over the TDC hole on the bell housing (2nd time mentioned).

Oh and then remove the AOS to replace the 2 "O" rings.

There are a few things I missed but you will notice them when they break or have deterioated.

GL
John_AZ
1988 924S + 1987 924S DD
1979 924 + 1977.5 924 + 1970 914 1.7 +++===gone, past tutors

[Techno Duck]

For a n/a only the intake has to come off. No need to drain the oil either. On a 951 it's a different story.. Turbo removal required.

[exitwound]

Originally Posted by WizPorsche944

Questions for you guys..

Do I have to take anything else off to get to these ?

As mentioned, the intake manifold has to come off. This is done by removing the 8 hexhead bolts surrounding the 4 cylinder intakes. Don't lose or mar up the intake manifold gaskets. If they look bad, replace them.

This means you have to remove the air box, which is a few bolts. This normally has to come off to do ANY job on the 944, so you probably know how to do this already.

Also, because the intake manifold has to come off, the fuel rail has to be disconnected. 4 bolts, 10mm hold it on. Be careful not to damage the tips of the fuel injectors when removing it.

Also, you have to remove the throttle cable from the throttle cam, and all vacuum lines that are in the way. Sometimes, the vacuum lines snag on me, sometimes they don't and I don't have to disconnect them at all.

The ISV (idle stabilizer valve) hoses that connect to the underside of the intake manifold are a pain. They're the small ~4" S-shaped ones. One have to come off the ISV in order to remove the manifold from the car. Good luck getting it back on. Position the clamp that holds it on in a particular way so that you can reach it to tighten it. If not, you'll have to remove it all over again to turn the clamp the right way.

The sensor bracket at the rear of the intake manifold has to be removed out of the way. This is a simple 10mm bolt. The sensors themselves don't have to be disconnected.

If you have a cruise control box, the secondary throttle that connects to it has to be removed from the intake manifold. A simple 10mm bolt again at the top of the intake.

The AOS is just attached by 3 bolts, 10mm i think? could be 13mm. It pulls straight out afterwards. There are 2 seals. 2 different sizes.

Do I have to drain the oil first ?

Nope. Though if it's been leaking around the seals, you may get a little dirty. Wipe up the oil while you're there.

Does this job make a mess ?

Not really. You end up taking a fair bit of the top of the engine apart, but the amount of oil lost should be zero.

If its only a dime sized oil puddle should I still do it ?

AOS leaks can lead to idle issues, oil in your intake, vacuum issues. It's not a hard job if you've had the intake off before. If you haven't, then it might take a few more hours.

I did this myself on my 86 NA and took a few pictures. You can see them here: http://www.theexitwound.com/944/index.php?subaction=showfull&id=1211581659&archive=&start_from-&ucat=2

[HondaDustR]

Here's more pictures

Fuel injector job in pictures.