How much to tighten O-ring fittings

Information on some common auto air conditioning topics.
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Osiris610
Posts: 3
Joined: Mon Apr 09, 2018 12:57 pm

How much to tighten O-ring fittings

Postby Osiris610 » Sat Apr 14, 2018 9:35 am

How tight should I make automobile O-ring A/C fittings? Is finger-tight enough?

Thanks, Mike Whalen
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Cusser
Posts: 319
Joined: Sun Apr 24, 2016 6:29 am

Re: How much to tighten O-ring fittings

Postby Cusser » Sun Apr 15, 2018 6:59 am

I do tighter than finger tight, but not gorilla; so that's not much help.

With an O-ring, the compression forces the O-ring to expand and seal. So I'm saying firm, and when you pull a vacuum or check with bubble solution after refrigerant fill, you should know if you need to tighten a tad more.

Use new refrigeration O-rings only, and oil them with a small amount of refrigeration oil before installing.
Osiris610
Posts: 3
Joined: Mon Apr 09, 2018 12:57 pm

Re: How much to tighten O-ring fittings

Postby Osiris610 » Sun Apr 15, 2018 9:58 am

Just what I needed to know. Thanks!
pete_89t2
Posts: 11
Joined: Thu May 04, 2017 9:38 am

Re: How much to tighten O-ring fittings

Postby pete_89t2 » Mon Apr 16, 2018 4:52 am

One other point you need to know about installing O-rings is to never install them dry. Always lube them with whatever compressor oil your AC system uses prior to installation.

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