C5 X7 Steering Rack - Again!

[MattBLancs]

Oh don't worry about me, I'm fine, just slip into Economy Mode Active more readily than I used to!

The little ones (one and four) are great fun and wouldn't change anything other than perhaps eldest not sharing every germ he's picked up at Pre school with the rest of us here would be nice!

Anyway I am going off topic as usual, so here's a relevant question to keep me in the good books:

Reading some of this long thread, I saw pinion in housing has:
Gear,
Alloy valve thing with O-rings,
Bush/bearing,
R21 lip seal,
Then at the top
Sound sort of rubber seal, dust seal??

Can anyone confirm this top item/ function, part number etc?

[bobins]

Then at the top
Sound sort of rubber seal, dust seal??

Can anyone confirm this top item/ function, part number etc?

I think it's supposed to sit in the rubber boot that's at the bottom of the steering column, but it rarely stays there and seems as much use as a..... <insert saying of choice here>

[Jay-Bruce]

I showed a mate of mine who's an industrial refridgeration engineer the pipes and problems we have with the steering rack. He was bemused about how they ever thought the aluminium pipe and steel clamping bracket would work well together and suggested the best fix for the ongoing issues would be a belt and braces approach of all three of a thicker 'O' ring, a thin shimming washer between the pipe swage and its seat, and some hydraulic sealing gloop for good measure. Either that, or graft in a new section of pipe.
As for making up a new pipe section - he's well used to putting swages into steel and stainless pipes, but never had cause to do so on aluminium, and the 'O' ring groove would add to the job.
Adding in a new pipe section for the last 6" or so of pipe wouldn't be a problem as he said just to use hydraulic compression fittings for the join as they come in all shapes and flavours for the job in hand.

The fridge-tech was the right guy to speak to as the steering rack fittings are more akin to refrigeration technology than they are to "real world" hydraulics.

[MattBLancs]

I couldn't resist any longer - so I set about taking my old spare leaking rack apart to see what I could see. And the result is... inconclusive.



After a bit of work the housing came off the shaft. The black ring sitting on the stud is a somewhat useless rubber dust ring that sits uppermost in the housing - this is the rubber seal you can see when you look down at the shaft on a steering rack.



Above you can see the single oil seal (a bit mangled) in the housing, and beneath that there's a thin bushing/bearing sitting in a bigger bushing - clearer on the next picture....



Looking from inside the housing you can see the thin bushing sitting in its larger ring.
See also....


The problem i've got now is how to remove the oil seal. The bushing and ring are in fairly solid and all the time they're sitting there the oil seal can't be removed. I'm presuming they're either threaded in or it's just an interference fit. The three pilot holes around the circumference lead me to think you need a three pronged tool to turn them to remove them.

Although it would be possible to fit a Speedi-Sleeve, unless you can get the old oil seal out to fit a new one, fitting a Speedi-Sleeve might prove a short term fix.

Ah, I've re-read this post, I see now what's been said - this is external to the pinion housing.

Presumably intended to deflect stuff away from the back of the lip seal, which is the uppermost item inside the housing.

Pinion housing in the oven at about 150°C was bush (and lip seal) removal strategy.

I'm thinking if of benefit to drill the aluminium housing for a grease nipple, exiting just above the lip seal. That would allow me to flood back of the seal with grease and hopefully prevent water sitting on top of the seal.

I know there was also discussion of the tiny green plastic ring, believed to be the "modified" shaft addition, hence why digging the photo out from here.

[darbuck]

Hi Matt be careful in the pinion housing the shaft has oil runs in it and is essentially a torsion valve which acts as the wheel is turned so introducing grease below the seal could risk blocking the oil channels. It will need further eyeballing to see if this is the case.ifit is possible to do, it would probably lighten the steering a bit due to lower friction at the seal face. What do you think.

[GiveMeABreak]

...and as it's all the same oil source for hydractive systems, you don't want any grease getting into the suspension circuit

[darbuck]

Exactly if you end up with it mixing you would never get it back out the car could be destroyed.

[MattBLancs]

All, good points, will leave it without nipple(s) then


(Just to be clear, was intending the grease to be fed above the lip seal, rather than below = agree below definitely a bad idea as you've both said would be mixing with the LDS. I'll have a think about it some more)

[darbuck]

I understand your logic though we will come up with a long term solution.

[Jay-Bruce]

I am not sure that "grease would kill the hydraulics", grease is merely an oil suspending a clay to create the gelatinous behaviour. I'm going to try dissolving some grease in LDS tomorrow at the workshop, will post my findings. I suspect that as grease is a clay suspended in oil to create a gel, the oil would dissolve the grease. I also suspect that if you had grease in a port with a pressure differential across it, and pressure is mereely force divided by area, the pressuirsed fluid would simply exert it's pressure times the area of the port in force onto the grease and push it to hell out of the way of fluid. I've built a few systems over the years where manufacturers have sspecified either petroleum jelly (vaseling - oo-err) or a light grese about the consistency of hand cream be applied to orings and shuttles, so I'm guessing that grease is unlikely to be the absolute of death to hydraulics systems?

[darbuck]

The issue is the amount of grease that would be pushed into the system through the nipple, would likely increase the viscosity of the oil causing it to clog small ports and channels over time. Potentially leaving parts of the system unlubricated even temporarily, could cause significant damage.Too much time on the rigs Jay vaseline eh

[MattBLancs]

My "buying parts I don't need, and hope to continue not needing them" has stepped up a notch this morning, now on order:

Stuff

From thebearingcompany.co.uk

This was cheapest price I could find the speedi sleeves for. Thought would be stung for £3.75+VAT postage on top but seems is free over £25. So will have 4 lip seals and two sleeves to go at when the time comes.

I've found a couple of tins that claim to be Belzona when making a start on my Grandad's garage clearing. Wondering if any good as expect they are forty years old! (unopened small paint tin type containers)

[darbuck]

Not so bad a new bad habit to accompany your Citroen buying problem

[MattBLancs]

Not so bad a new bad habit to accompany your Citroen buying problem

Anyone who has seen the state of my garage would argue it's definitely less stuff I need rather than more "in stock, will come in handy"

[darbuck]

you and me both I have a shed full of car junk from over the years.