850 steering rack teardown and rebuild

[Chuck W]

So, I've been chasing around a rattle in my 850's passenger front corner and a few months back, after going through EVERYTHING on the front of the car, I narrowed the noise down to the rack itself. Specifically, it sounds like the rack is a little loose in the housing plug (The big white plastic piece at the end of the rack housing).
When I did the manual swap on the car, the rack was fine, but seeing as I had things apart, I replaced the outer rack seal on the PS. Other than that, original rack to the car (217K).
When I swapped out tie rods on that side chasing the noise, I did find a little fluid leakage and a sharp "whack" on the end of the rack can cause a clunk sound.

Now, I have the old TRW rack from my wife's '97 GLT (which we replaced with the rebuilt unit from my old '96 GLT).


I got that all torn apart and am working on getting it cleaned up.
Going through the seal kit I picked up for it, I found that it didn't come with the inner oil seal, only the outer. Looking through the remnants of the other seal kit I had bought when I replaced that outer seal before, I didn't find another oil seal, but I did find a set of the seals that are used on the valve drum on the pinion assy, as well as for the rack valve in the middle of the rack.

The old write-up on the rack rebuilding that I pulled down says leave these alone, as they are "non-serviceable". Is that true? I mean, you can't wrestle them on like regular o-rings (they are rectangular in cross-section, and not super stretchy), but with some light-handedness, I think replacement should be possible.


Anyone have any experience in this?
I need to order more seals anyway, so I have a little time to kill on this.

[abscate]

The Volvo uk group might have some more on this, I’ll drift around the web this am while watching

Is the kit you bought?

https://usparts.volvocars.com/p/Volvo__ ... 71558.html

[Chuck W]

It was not. I don't recall the manf of either kit, but both were specified for TRW racks.

Right now the biggest PITA is getting the lower pinion seal out of the housing. It's "glued" in place, which is making things difficult.
I need to sort out what "hydraulic adhesive" actually is for when I install the new one. Everything else is gravy.

[abscate]

I’m still wrestling with if I should pull the OE rack of Shagg before sending to crusher. It’s got 250k miles on it, didn’t leak. I do have engine out so rack is an easy pull. I probably will as I want the alloys , and once I commit to flat bed , off comes the rack

(Apologies for thread drift)

[Chuck W]

A little heat helped to dislodge the lower seal.


Working up a plan on those pinion drum seals. Gotta CAD up something first.

[jreed]

Thanks for writing this up and especially the photos -- very sharp. Much appreciated!

[Chuck W]

So, I printed up this little taper tool to install those seals, with minimal stretching.


When I get the extra seals, I'll give this a go. What I'll do is wrap some electrical tape around the drum barrel and expose the grooves one at a time. I'll install the furthest one first and work back towards the tool.

[Sveedy]

Love it ! ^

[foggydogg]

Many years ago I saw a guy in a transmission shop use kitchen cling-wrap to get those square shoulder seals over splines. ( To date the memory, he was working on a Slim Jim. You Youngsters look it up.) The transmission assembly lube those guys used looked a lot like Vaseline with a bit of ATF mixed in for color - and to reduce viscosity a half-point or so.
Great writeup. Soldier on.

[Chuck W]

My new seals have been taking the slow truck from the west coast. Hopefully I'll have them in a couple days.