Leaky PS pump V8

TXMatti · Post by **TXMatti** » 26 Jan 2020, 13:16

Allright, lets get real specific here...

So the patient is a 2009 XC90 with the V8. Issue is that it keeps puking power steering fluid from up top near the pump. Judging by previous posts on this forum, could be very likely it's a blown O-ring up there.

So, here's my question... Do I have to take the upper plenum out and open up the cooling system to do this, or is there a way to wrangle new o-rings in there without tearing the whole place apart?

Post by **ggleavitt** » 27 Jan 2020, 17:40

See photo, you can probably get to the high pressure side in place (O-ring is PN 988119). Power steering pump (exch) is PN 36000748, will be happy for you if it's only the o-ring. Plenum upper gasket are PNs 30720327 and 30720328 and if top comes off, you'll need to drain some coolant (good time to swap out with OE). My seeping was from the back seam, replaced before it got worse and still have the original pump- if someone knows where to get them quality rebuilt, let me know. When pump comes off belt comes off. If the vehicle is over 100k and the tensioner and idlers have already not been replaced, probably good time to do them all together. Keep the tensioner bracket if you do replace, you'll use it again some day.

Sunstar33 · Post by **Sunstar33** » 31 Jan 2020, 08:28

Dealer wont sell specific o-ring . so heading to autoparts and finding a correct size is a easy fix for about 5 bucks.

Post by **ggleavitt** » 31 Jan 2020, 12:08

The steering rack side (high pressure) o-ring is readily available, PN 988119 as noted above. Reservoir (pump fluid input) side o-ring is not a replaceable PN on it's own, see photos for reference. I took a micrometer to the o-ring: approximate measurements are 14mm ID, 17mmOD, and 2-3mm thick (mine are flat on the sides).

88domer · Post by **88domer** » 25 Mar 2020, 15:15

Okay, as you know ggleavitt, I’m embarrassed that I didn’t come here first.

Quick question - does the pump come with the reservoir o-ring already installed, or will I need to track down one at a hardware store before I tackle this? Already have PN 988119 on the way with the pump and intake manifold gaskets.

Thanks as always!

BD

Post by **ggleavitt** » 26 Mar 2020, 16:58

No need to get anything, pump will come with that piece already bolted on. I took it apart (it's my old pump waiting on someone smart to start rebuilding them) in order to get a photo of the o-ring which the earlier poster had specifically asked about. If you have the rack side o-ring 988119, you're good to go.

Welcome to MVS!

88domer · Post by **88domer** » 28 Mar 2020, 06:59

Thanks, glad to be back on the forum! Got the pump out yesterday; didn’t take pics because I was in a rush to get to the dealer to pick up parts for one of my other Volvos before they closed for the weekend, and wanted to get the core charge back. It looked to be in good shape, but at this point I’m not taking my chances.

Lots of inspection to do today on the area after I get the idler pulleys and tensioner out. Hoping that was the only issue, but still worry there was collateral damage to hoses that caused the loss of coolant and ps fluid.

BD