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Heat coming up through tunnel

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Old 04-01-2010, 11:19 PM
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jpitman2
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Default Heat coming up through tunnel

On anything like a warm day after a half hour or so I start getting quite a bit of heat coming up around the area of the window/sunroof switches. Obvious next thought is engine mounts, but I have NO other symptoms consistent with this - no vibration of any sort at any speed that feels like engine related, and I have looked for signs of sagging down there to no avail. My suspicion is the PO had something done and the insulating pad is damaged or incomplete. Does anybody have a pic please of the relevant foam thing that is supposed to be up there ? I cant even find it in PET so far, but havent given up yet. Is it possible to push one up there (if missing) without dropping the TT ? Will the exhaust have to some down?
Found the part - 928 424 182 00 for Autos, early. Looks big.....
thanks
jp 83 Euro S AT 52k
Old 04-01-2010, 11:21 PM
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Rick Carter
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I would still guess MM.
Old 04-01-2010, 11:34 PM
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dprantl
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Here it is. I'm not sure you will be able to get it up there without dropping the TT. I also doubt that it is completely missing on your car.

Dan
'91 928GT S/C 475hp/460lb.ft
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Old 04-02-2010, 12:04 AM
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jpitman2
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Thanks guys. Looks like its time to get it on a hoist and find out for sure if the mounts need doing, or what?

jp
Old 04-02-2010, 12:09 AM
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Stromius
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Just look at the hooks of the motor mounts. You can lie on the ground and peek in behind the passenger wheel to see if there's a finger's width or more of gap. I have about that and a bit and am planning a MM/OPG job very soon....good times right
Old 04-02-2010, 12:19 AM
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Dave928S
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Hi John
My guess is that the seal below the main boot on your shifter might be torn. I would also doubt that your insulation is missing as you have to take heaps out to even get at it. On a manual the tunnel insulation is just that and wouldn't let a draft of hot air through, the boot on the gear lever is just window dressing and the part that does the sealing of the tunnel opening is what is referred to as the frame .. weird name to call it. Looks like part 25 on the diagram. I was thrown off target by the description on the manual parts diagram, but sure enough the frame was a rubber boot. Can post pics if you like .. but mines manual of course.
Dave
Old 04-02-2010, 12:25 AM
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Dave928S
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oops ... looked at that and thought it was tunnel insulation and its the torque tube foam block ... still almost impossible to get to with TT in though. Still reckon rubber seal below boot. let me know if you want pics.
Old 04-02-2010, 12:45 AM
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Dave928S
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Here are some pics of the foam TT noise absorber and the seal which is under the shifter boot ... mine was letting hot air in where the seal was split.
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Old 04-02-2010, 12:48 AM
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jon928se
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Originally Posted by Dave928S
oops ... looked at that and thought it was tunnel insulation and its the torque tube foam block ... still almost impossible to get to with TT in though. Still reckon rubber seal below boot. let me know if you want pics.
Definitely impossible to install without dropping TT. Will probably come out in un-reusable pieces without removing TT though.
Old 04-02-2010, 12:57 AM
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Lizard928
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You can use "the great stuff" expanding foam to make up the difference for missing material.

Redoing the MM will help though.
Old 04-02-2010, 12:59 AM
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Dave928S
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Jon
If you can see it there it will be OK because it's not a perfect seal anyway. Air can travel along the shifter shaft hole in the foam and get to under the console because its not a tight fit. They're originally held on with a couple of bands of PVC tape .. looks like. It seems to me that they principally keep the shifter parts free of thrown up water and dirt and have a marginal affect on insulating. The rubber seal is accessed from the top under the centre console and is held in place by a metal surround and could definitely allow hot air to under the switches.
Old 04-02-2010, 01:14 AM
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Valentine911
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having same issue with heat coming up on my '83 S Auto trans. Just took it out of storage, so it's going into the shop tomorrow for an oil change, so I'll have it looked into...
Old 06-01-2010, 02:43 AM
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jpitman2
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Anybody know from experience whats involved in lifting enough of the shifter stuff (on a 3speed, from the top side) to check the rubber boot please?
jp 83 Euro S AT 52k
Old 06-01-2010, 03:18 AM
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Dave928S
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On mine the plastic frame which is at the base of the leather boot has a plastic projection which clicks into the opening at the back and front.

All I did to remove it was push/flex the frame forward at the back which allowed it to disengage from the opening and it lifted up and out. I have no idea how your 3 speed auto top boot/cover compares, but imagine it would clip in similarly?? ( a manual type boot is sold to replace the traditional auto one so I would think it should just click in).

Once you have that out you can see the boot which I showed a pic of in post 8. Mine was letting heaps of hot air in and heating up that back section around the switches, even though the foam below was OK (it doesn't seal well)
Old 06-01-2010, 03:21 AM
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jpitman2
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Thanks Dave, I will check out mine in more detail next opportunity....not such a big deal now thats itscool down here, but still needs fixing.
jp


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