Well after going through the HVAC system earlier in my 87 5 speed, I learnt that I had 2 pods which were not holding vacuum.

The recirc flap, and the one under the pod.

Well I had 2 of these in good nik off another car. So I decided to tackle the recirc first.

I looked at it and in order to do this one really must remove the entire recirc flap from the car. Not something I relish doing.
Reason is that you have to practically remove the fuse panel from the car. And then you have to reseal the piece to the car.
So I looked at a recirc flap that I had sitting in my garage. I decided to simply cut a circular hole in the recirc box above the vacuum pod. I first removed the blower motor, and then disconnected the pod and shuffled it out of the way so as to prevent damaging it. I then took a air rotary tool with a large viened cutter, and worked out a nice area, not damaging any of the box other than the area to cut. I then pulled the old one out the top, and popped the good one in. Clipped it back into place and reattached the arm.
Then I tested it with a vacuum guage and buttoned it back up, and reconnected the power to the vacuum solinoid to that pod. I then tested operation and it worked perfectly.

The other pod was extremely easy with the dash pod out of the way.

I also reran the solder on another cruise control brain and tested it confirming its functionality after the repair too. I would recommend to remove the protective coating off the back before resoldering, it gives off some nasty fuses, and prevents the solder from running nicely when thick.

I just thought I would post this up for any of you who might be interested in performing this modification to the box to be able to replace the diaphram without requiring the removal of the entire recirc flap.

I cannot see any real downside to doing this, and it will never be seen either.

 

Colin........there's some that believe the 928 design has no faults; you, I and many others differ.

Thx for the tip

 

every car has faults just some have less than others.

 

Do you have any pics of this process / modification. Sounds great but I need to see it if possible.

 

I will get a picture of the recirc flap that is in the garage and draw a line on it photophop to show where I made the cut. I cannot show you it on the car as it is back together. And in typical fashion, I finished up and then thought damn I should have gotten a pic or two of that!

 

you are the only one I know who tackled this, it is not worth the effort for others so I don't actually know anyone else that actually did this, good work!
for the rest I usually follow pirtle's write up:
http://members.rennlist.com/pirtle/svc_act.html

 

Colin will any of these pics work to photoshop?

http://members.rennlist.com/v1uhoh/air.htm

 

The hardest part about replacing the recirc diaphragm is getting the blower motor out and then realigning the hood.

After that, you don't need to remove the fuse panel - just unbolt it and lay it forward. The only trick to installing the recirc airbox is getting new strip caulk - easy.

Colin - did you test the water integrity of your mod by pouring water around the blower after you'd put it back?

 

When I did the recirc on my 89 I followed this write-up here:

https://rennlist.com/forums/928-foru...vaporator.html

Look further down than the top post for more pics.

Nice idea Colin, how'd you seal up the hole afterwards? Silicone goop? A pic showing hole location would be good for when/if I have to tackle this on another 928

 

Getting the blower motor out really is something else. If you guys saw a video of me trying to get this thing out, you'd pay to see it again... Embarrassing...

 

Ok I will put up pics in a minute.

However to answer some questions.

Worf, you are correct you do not have to remove the fuse panel, but it makes it easier as you have to pretty much remove the two supports for it. And cleaning that goop and relaying more is messy work that I would rather avoid. As to the water, the plastic trim is above this and keeps most of the water out. However irregardless, I did still test it and there was no additional water that entered the cabin.

Hilton, I did not seal the hole at all after making it. No need to.

BB, Yes getting the blower motor out is a pain. However for this entire process I did not remove the hood from the car. I put a pair of vicegrips on the drivers side shock to hold it up and removed the 2 bolts on the passengers side. This allows you to simply raise that corner of the hood for extraction of the blower motor. I also remove the screw and bolt allowing the wiper trim to be lifted slightly so as to avoid damaging it.

 

Ok,

I just grabbed this picture from one of the other links, Rich if you have a problem with me using it let me know.

The circular area is what I cut out. When cutting it watch where the red arrow is, this is one of the tie down area for the blower motor and you need to leave this intact. But the area below the red section is of no importance and can be removed without any problems.

To remove the vacuum pod I just reached in unclipped the plastic connector holding the pod to the metal arm. There is no need or point to removing the c-clips. But if you do, you dont need to worry about putting them back. That metal arm can go nowhere anyways. Once the plastic connector is undone use your finger and lift up on the top two plastic locking feet holding it onto the recirc flap. Once you do it will pop out (easily I may add). And removal and reinstallation is pretty easy. Though you may consider having a hand vacuum pump on hald to pull the pod closed a little to aid in the attachment of the plastic adapter after installing the pod back on.

 

Getting the blower motor out/in wasn't as big an issue as getting the 'condom' to reseal..........PITA.

 

If you do this outside the car, and simply stretch the outter ring a little it is alot easier.

 

Zoltan,

People were replacing vac pods years ago. I should know, I was one of them. Check the archives.