Spare McMaster AOS O Ring Cap seal?

Talk and Tech about turbocharged 924/944/968 cars
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Glassmuseum
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Hi! I am about to pull/replace my turbo and will be doing the AOS seals as well. just checking to see if anyone has a spare McMaster O Ring- https://www.mcmaster.com/product/9396K172 that replaces the top cap O Ring for the air oil separator.

I was about to hit the order button but seems silly to spend 25 bucks with shipping on a 10 pack if someone has one laying around. Happy to throw a few bucks if someone has a spare. Thanks!

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PSU_Crash
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Glassmuseum wrote: Tue Apr 21, 2026 8:39 am Hi! I am about to pull/replace my turbo and will be doing the AOS seals as well. just checking to see if anyone has a spare McMaster O Ring- https://www.mcmaster.com/product/9396K172 that replaces the top cap O Ring for the air oil separator.

I was about to hit the order button but seems silly to spend 25 bucks with shipping on a 10 pack if someone has one laying around. Happy to throw a few bucks if someone has a spare. Thanks!
I have spare seals for this very reason and I'd be happy to send you one. When I get home this evening I'll grab the specs and send you a message.
'86 Zermatt Silver 944 N/A :thumbup:
'86 Mitsubishi Starion - Purpose built SM class Autocross car
'87 Chrysler Conquest - Mid LS Swap

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Glassmuseum
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Amazing @PSU_Crash ! Really appreciate it.

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michaelmount123
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This o-ring may be suitable, but I imagine the original is a metric piece. McMaster carries metric too.

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PSU_Crash
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This is the o-ring I used on mine. 2k miles later and it's still good. I call that a win. 8-)
If you got this far you haven't detroyed the cap while prying it off. Congratulations!

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'86 Zermatt Silver 944 N/A :thumbup:
'86 Mitsubishi Starion - Purpose built SM class Autocross car
'87 Chrysler Conquest - Mid LS Swap

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Glassmuseum
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PSU_Crash wrote: Tue Apr 21, 2026 4:07 pm This is the o-ring I used on mine. 2k miles later and it's still good. I call that a win. 8-)
If you got this far you haven't detroyed the cap while prying it off. Congratulations!

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Appreciate you! Just sent over my address via pm.

And yes if you have any good pointers lmk. I did this once with a NA I had a few years ago and it mostly went well. Trying to find a cheap used turbo AOS as backup bc i’m anticipating something getting cracked.

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PSU_Crash
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I followed NC944er with his method and used a little heat gun action. Much harder to remove than I had anticipated!
https://www.youtube.com/watch?v=lGaXEykh7nI
'86 Zermatt Silver 944 N/A :thumbup:
'86 Mitsubishi Starion - Purpose built SM class Autocross car
'87 Chrysler Conquest - Mid LS Swap

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