8 cylinder front engine iconic vehicle
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By ChrisZ
#176601
The other day in a storm my 86.5 928's alarm decided to go off. Not the horn, the factory alarm.

I disabled it by disconnecting the battery, but I noticed that the passenger tray was damp, which means a rain infused water leak (not the AC unfortunately). Car is slightly nose-down, rain trays are good and installed.

Where might the leak be coming from? I pulled and replaced the AC blower fan over the summer, is it possible it's leaking from there and if so do I need a new seal at the bottom of the blower?

Thanks!
Chris
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By worf
#176609
ChrisZ wrote: Sat Oct 15, 2022 2:10 pm but I noticed that the passenger tray was damp,
The interior parcel shelf?

ChrisZ wrote: Sat Oct 15, 2022 2:10 pm Where might the leak be coming from? I pulled and replaced the AC blower fan over the summer, is it possible it's leaking from there and if so do I need a new seal at the bottom of the blower?
In short: yes. Did the new fan come with a seal? What was the condition of the original seal?

Long story:
Recirc box seal (strip caulk) is a leak possibility if it has ever been out and was not specifically tested upon install.
Recirc flap seal.
Seal between fan and recirc box. But, more likely - if there *is* still a seal there - is that one or more of the three screws is missing, or that the rubber bellows between the fan and HVAC air box isn’t installed properly.

Dump water on it, and then look up there and see from where the water is coming. (Remove parcel tray, disconnect battery, withdraw brain case.)
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By ChrisZ
#176615
New fan used my existing housing. Seal was there but kind of meh. Is the seal sold separately?

Hm. I'll take a look for the screws, maybe I forgot to install one. Off the top of head know what kind of screws they are?
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By worf
#176621
ChrisZ wrote: Sat Oct 15, 2022 5:07 pm New fan used my existing housing. Seal was there but kind of meh. Is the seal sold separately?
It was: 92857413302

Now, NLA. It’s just a circular closed-cell high-density foam piece, IIRC.
ChrisZ wrote: Sat Oct 15, 2022 5:07 pm Hm. I'll take a look for the screws, maybe I forgot to install one. Off the top of head know what kind of screws they are?
Two 8mm-hexhead coarse-threaded screws about 16mm length from the top-side. One under the hood hinge, the other (the bitch one) in the middle of the air outlet.

One 10mm-hexhead coarse-threaded screw about 25mm long that goes in from the fuse panel side through the recirc box into the base of the fan enclosure.
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By linderpat
#176780
don't forget to look at the drain area behind the rubber flap in the engine bay, passenger side - if that gets clogged with debris, then leaks into the cabin by the CE panel happen.
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By ChrisZ
#177646
Oh, the 10mm inside one. I *totally* forgot about that and of course that is right under where the leak is. THANK YOU! Should I put any sealant on the bolt?

When I took out the blower I cleaned under the bracket it is on, there was so much crap there it was insane. Vacuum, then claw grabber then endless pulling bits out with pliers. Fortunately no rust. Much more airflow....
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By worf
#177649
ChrisZ wrote: Thu Oct 20, 2022 9:16 pm Oh, the 10mm inside one. I *totally* forgot about that and of course that is right under where the leak is. THANK YOU! Should I put any sealant on the bolt?
3M strip caulk. Wrap a pea-sized glob around the shaft at the base of the screw and install it.
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By ChrisZ
#179339
Got it. Just to be clear, that's a 4.8*50mm tapping screw? I don't remember having one of those around here. I take it you have to hold the fresh air flap open to get it installed?
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By worf
#179408
ChrisZ wrote: Fri Oct 28, 2022 11:28 pm Got it. Just to be clear, that's a 4.8*50mm tapping screw?
If you’re asking me if that is the exact size: I don’t know. Seems about right.

Parts diagram says you are right.
ChrisZ wrote: Fri Oct 28, 2022 11:28 pmI take it you have to hold the fresh air flap open to get it installed?
Nope. Not even a bit. There’s two holes in the recirc box on the trailing edge. One of those holes gets the screw. Which hole? The one that leads to the fan enclosure.
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By ChrisZ
#179688
worf wrote: Sat Oct 29, 2022 11:51 am Parts diagram says you are right.
Yep, found it in the PET. Then ordered it from a proper 928 vendor, this might be the smallest $ value order, but I'm ensured of getting the right part. Nothing like a screw too long going into the fan blades or whatnot.
Nope. Not even a bit. There’s two holes in the recirc box on the trailing edge. One of those holes gets the screw. Which hole? The one that leads to the fan enclosure.
Okies, I'll look for it. Thank you!
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By ChrisZ
#181656
Wow. Ok, trying to figure out where this screw goes *sucks*. I took off the tray so I could get in there and took a look.

The screw goes somewhere in the fresh air vent above and to the car's rear of the fuse box. I can see that. However there is the fresh air/recirc flap in the way and with the car off it's closed.

Fired up the car, the flap does open but I can't get my head or a camera in there to see where the bolt goes in. Anyone got a picture of it installed or something to help guide me other than pull the passenger seat so I can fit my head under there?

It's always the little things that are the biggest annoyances
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By Gary Knox
#181659
That is probably the screw installed by Helga, the person with the smallest hands in the production line. Maybe even the first part itself installed during fabrication of the car!! Good Luck.

Iit seems there are MANY items on my 928's that required hands the size of my 10 year old granddaughter and strength similar to Arnold Schwarzenegger to access/repair..
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By worf
#181709
The flap has nothing to do with this fastener. It can be open, closed, or mooning you.

I’ll see if I can dig up a picture or take a new one as I have two loose recirc boxes at the moment.
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By worf
#181817
The first picture is from the reference point of the passenger seat. The fan is flipped over the horizontal axis. Fastener locations are circled.

Image

This, second picture is as if you were upside down in the passenger well with your legs draped over the seat back. The fan is slightly offset from the box so that you can see your problem holes.

Note the blob of strip caulk on the box used to seal the screw.

Image
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