I replaced mine about a year ago because it was “wet.” What happens is the pair of o-rings inside the connector harden/shrink/take a “set” and then leak fluid and/or admit air. It was not dripping but the way these are put together, they more so ‘weep’ than drip when they are bad. Because leaks at high pressure connectors tend to suck air when running and leak fluid when stopped – but that fluid tends not to be under much pressure so not much leaks out.
You can replace the o-rings in the connector if you can figure out what size they are, HOWEVER it’s likely you’ll damage them on the way in if you do because of how they are installed. And, since the connectors are standardized, actually they are cheap. Here is an example: https://www.amazon.com/AUTOHAUX-9-89mm-Release-Connector-Disconnect/dp/B0BR95T2XK
You can cut the power steering hose just after the connector on the quick release (there is just enough slack in the hose if this has not already been re-terminated), then install the new connector and snap it onto the PS reservoir nipple. To install the new connector you will want to use a single-ear hose clamp. Here is an example: https://www.amazon.com/Hydencamm-250PCS-5-3-33-1mm-Stainless-Automotive/dp/B0CZRSYZBM – yes they are exactly the same type as people now use to secure PEX plumbing connectors. Some people call them Oetiker clamps. You just need the clamp rings that will fit, I think they are 10mm or 10.5mm or so and that size will be among the zillion (well, 200+) that you get in a kit such as I shared a link to.
The connector size will be printed on or molded into the connector you currently have – check that and then get the connector. A “full line” auto parts store is likely to have them. In my area that would be a NAPA or Advance Auto. The parts are not pricey if you can find them locally but if it matters to you they will be cheaper if you do a web search for them and order.
I replaced mine because my power steering pump seals had failed and so there were problems; replaced the pump and still had leaks from somewhere as when I put vacuum on the reservoir the system kept drawing air from somewhere or other. So I replaced all the o-rings at the connectors (most of them just unscrew) to the pump and rack. A friend of mine, local mechanic, looked at the reservoir connector and said “it looks like a fuel line connector but that’s the power steering line, most steering lines just screw on, I’m not sure what’s going on here.” So I took a cellphone snapshot of it and started investigating. Volvo does not list a part number for it in my VIDA, probably because it’s supplied along with the power steering hose. At the time our cars was made, though, it was a Ford platform (EUCD) and you can bet Ford had a Volvo SKU for that part listed somewhere, or else tracks them as shop spares by the generic SAE description of something like “9.89 ID6 8×6 90”. I searched for the RAY 9.89″ molded into the part and it did not take long to figure out that any fuel line connector the right size would work fine. Looking at how it was connected with a single-ear clamp, I had to do some more digging and found out how those are installed and removed (with the same tool, basically a pair of nippers).
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