hvac vacuum actuator replacement diaphragms
08-21-2006, 12:21 PM
#32
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Gordon,
I agree with H - it is far easier to change out the diaphrgm than the complete unit as they are rivited in place.
Roger
I agree with H - it is far easier to change out the diaphrgm than the complete unit as they are rivited in place.
Roger
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
08-21-2006, 01:24 PM
#33
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Originally Posted by ROG100
Gordon,
I agree with H - it is far easier to change out the diaphrgm than the complete unit as they are rivited in place.
Roger
I agree with H - it is far easier to change out the diaphrgm than the complete unit as they are rivited in place.
Roger
11-20-2007, 12:07 AM
#36
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Did the guy ever make the smaller ones?
The "guy" was me - Roger@928sRus.com - and no I did not due to the high tooling cost.
I have the rights to the sale of Porsche Recirc. diaphragm - for what that is worth.
They are $10 each including shipping in the USA in most cases.
Still working on the smaller diaphragms and I WILL get them made somehow!!
The "guy" was me - Roger@928sRus.com - and no I did not due to the high tooling cost.
I have the rights to the sale of Porsche Recirc. diaphragm - for what that is worth.
They are $10 each including shipping in the USA in most cases.
Still working on the smaller diaphragms and I WILL get them made somehow!!
07-23-2018, 10:22 PM
#38
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I know that this is a pretty old thread but I'm getting started with restoring an 83' 928 which has the riveted attachment method. I've read that the part #928-573-077-04 is a replacement for part #928-573-077-03 which I'm beginning to think might be the riveted part. Does anyone know whether the diaphragms are interchangeable? And if not, how in the heck does the later part attach?
07-24-2018, 11:10 AM
#39
Burning Brakes
I know that this is a pretty old thread but I'm getting started with restoring an 83' 928 which has the riveted attachment method. I've read that the part #928-573-077-04 is a replacement for part #928-573-077-03 which I'm beginning to think might be the riveted part. Does anyone know whether the diaphragms are interchangeable? And if not, how in the heck does the later part attach?
New style diaphragm on left.
Old style vacuum pod attachment method. Pry off the metal retainers with a screwdriver.
New vacuum pod clips onto the recirc box with four plastic protrusions
I applied a pattern to enlarge the center hole and for the mounting points
I did my best but it is awkward to get at with the ledge above.
It was a pretty secure fit but for piece of mind I JB welded the base of the vacuum pod to the recirc box. If the diaphragm ever goes bad again you just replace the innards anyway.
Retrofit complete.
It works perfectly.
After I wrote this out I found the discussion thread https://rennlist.com/forums/928-foru...acuum-pod.html
07-24-2018, 04:10 PM
#40
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Nice work Mr. Moose. I say never be too proud to use JB Weld in the right circumstances.
I hope Roger will chime in here and correct me if I am wrong, but I believe he has the "smaller" diaphragms for the comb and footwell actuators made out of a superior silicone rubber but only has the entire actuator for the "larger" defrost and recirc flaps. For cars with the "snap in" recirc actuator old threads indicate that a Mercedes "single" diaphragm available here - http://www.perfanalysis.com/climate-...acc-version-i/ - will fit the recirc actuator. I have not verified this but have an example being shipped to my hacienda.
Are the diaphragms for the recirc and defrost interchangeable?
I hope Roger will chime in here and correct me if I am wrong, but I believe he has the "smaller" diaphragms for the comb and footwell actuators made out of a superior silicone rubber but only has the entire actuator for the "larger" defrost and recirc flaps. For cars with the "snap in" recirc actuator old threads indicate that a Mercedes "single" diaphragm available here - http://www.perfanalysis.com/climate-...acc-version-i/ - will fit the recirc actuator. I have not verified this but have an example being shipped to my hacienda.
Are the diaphragms for the recirc and defrost interchangeable?
07-26-2018, 12:35 PM
#41
Chronic Tool Dropper
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Alex & the Group --
From your pictures it looks like the diaphragm for the replacement actuator is a tad shorter in the cup than the original, has same length rod/link attached, and same diameter as the original. If this is correct, does the new part have the same available stroke as the original? I'm trying to remember if/how this might be important for the recirc flap especially. I think that's the only one I haven't replaced.
From your pictures it looks like the diaphragm for the replacement actuator is a tad shorter in the cup than the original, has same length rod/link attached, and same diameter as the original. If this is correct, does the new part have the same available stroke as the original? I'm trying to remember if/how this might be important for the recirc flap especially. I think that's the only one I haven't replaced.
07-26-2018, 06:09 PM
#42
Burning Brakes
I cannot say for sure, I replaced the whole unit. I could take apart the old defrost vacuum pod and measure the diaphragm if that helps.
The new part has the exact same stroke and fully opens and closes the recirc flap.
If this is for your '89 then it should be a direct swap, no retrofit needed.
Alex & the Group --
From your pictures it looks like the diaphragm for the replacement actuator is a tad shorter in the cup than the original, has same length rod/link attached, and same diameter as the original. If this is correct, does the new part have the same available stroke as the original? I'm trying to remember if/how this might be important for the recirc flap especially. I think that's the only one I haven't replaced.
From your pictures it looks like the diaphragm for the replacement actuator is a tad shorter in the cup than the original, has same length rod/link attached, and same diameter as the original. If this is correct, does the new part have the same available stroke as the original? I'm trying to remember if/how this might be important for the recirc flap especially. I think that's the only one I haven't replaced.
If this is for your '89 then it should be a direct swap, no retrofit needed.
07-26-2018, 06:59 PM
#43
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I used to sell the diaphragm for the recirculation actuator - Mercedes part and it was similar but not exact dimensionally to the defrost diaphragm.
Some were able to fit it and get it to seal in the defrost position but many others could not.
As the recirc. and defrost are relatively inexpensive as complete actuators I have not really looked for a replacement diaphragm.
I do have the diaphragms for the footwell and center actuator (in the center console) for $56 each.
Some were able to fit it and get it to seal in the defrost position but many others could not.
As the recirc. and defrost are relatively inexpensive as complete actuators I have not really looked for a replacement diaphragm.
I do have the diaphragms for the footwell and center actuator (in the center console) for $56 each.
