THIS is why you must remember to depressurise

[Stickyfinger]

THIS is why you must remember to depressurise .......... never forget to do it when working on older Citroen models

[Jay-Bruce]

This thread should be stickied.

I used to carry my (now lapsed) British Water Jetting Society card in my wallet, on the back of the card it had medical instructions, the injection wound was to be treated like a gunshot wound. Also worth noting is that the residual oil that remains inside an injection wound, like the blue paint that remained inside the gel in the video, starts necrotising (killing) the surrounding flesh, as such doctors have to resort to cutting, like napoleonic era battleship surgeons, injection in the hand will likely mean losing the lower arm etc...

If you get a leak, do not try to dive in and intervene, no nipping up a fitting, dabbing a rag to it to stem the flow or trying to see where it's coming from, doing those sorts of things with a water pipe in your household plumbing will get you wet, whereas doing that sort of thing with a hydraulic pipe will get you maimed or killed.

Old citroens could be depressurised by undoing the 12mm bolt on the top of the regulator/accumulator 1/4(?) of a turn and the suspension would instantly drop. After depressurising the system with this screw, leave it "open" and give it time to drain any residual pressure before breaking containment.

New citroens need a laptop to tell the BHI to depressurise the system, but on hydractive 3+ there is also a bleed screw on the firmness regulators try and free this up on your car and open it AFTER depressurising with a laptop. Then, you can depressurise with the laptop and open the bleed screws to prevent the system being able to inadvertently repressurising behind your back. Similarly, after depressurising with a laptop, disconnect the battery to prevent the BSI & BHI from having a conversation you're not privy to and deciding to fire up the pump inresponse to movement of the height sensors as you lark about with the suspension stuff. All these steps are about putting barriers between you and pressure.

Fun fact, the diesel injection system is even more dangerous than the hydraulic suspension system!

Common Rail Diesel Injection systems run at anywhere from ~11,000psi to ~30,000psi vs the < 3,000psi in the suspension system. Also, the nature of hydraulic oil vs diesel means that diesel's chemistry is more aggressive in its attack on surrounding flesh in an injection wound.

[Gibbo2286]

One of our neighbouring garage men was using a compressed air grease gun, back in the days when all cars had grease nipples, he slipped and pumped grease into his finger, just squeezed it out and carried on, two days later he was in hospital with blood poisoning, from which he didn't recover.

[Doo]

A friend of my dad was engineer on a large fishing vessel. One day, an oil leak started on a part of the engine, so he put his thumb over it....blew his nail off!! I believe he had to be airlifted to hospital where from memory, they removed his thumb.

I think of hydraulic systems as explosives. To be treated with respect. I am genuinely scared of my bearing press

[Stickyfinger]

I am most pleased people are watching this .....

[momag46]

I worked as an inspector at Fiat Allis in the late 70s, early 80s. They made wheel loaders with a bucket on the front. To test the hydraulic pressure we used to put the bucket on the floor and work all the system with the engine off to depressurise the system. Then, on a set of steps, remove a plug and fit a pressure gauge. One of the guys did all that but the bucket wasn’t flat to the floor, the front edge was up be about 2”. As he removed the plug, a jet of oil hit him in the chest knocking him off the steps and he finished up on the floor with a massive bruise on his chest. Everybody was much more careful after that.

[royturbodiesel]

I wasn't aware that this was such dangerous.
In my youth, I was working on a 1982 CX Reflex D, and opened the pipe from the accumulator.
The beam of LHM hit me straight in the face, coverong my head in oil.
I do believe that was wearing glasses already then, and after reading this thread,
I understand the I have to give thanks to our heavenly Creator for protecting my sight and life.
This was back in 1991, and I've had respect for this in the latter years,
but I was todays years old when realizing how dangerous this really is.

[tomsheppard]

Sound advice. For the last twenty odd years, my toolbox has carried a slightly modified 12 mm ring spanner for the purpose. I usually get the car onto four axle stands then fully lower the suspension before depressurising the system with only one exception. Rear spheres on a BX estate. Rear cylinders are frail and simply unobtainable. Rear spheres are often Very tight so I sometimes need to give the sphere tool a fourpenny one to just shift it. This is better done under pressure or something breaks. Once it budges, I can release the pressure. I do this for each rear sphere in turn if the car is new to me, repressurising once the first sphere is changed

[Old-Guy]

As an apprentice at a diesel manufacturer back in the late 60s, it was hammered into me that "fuel injection" is exactly what is likely to happen to anyone careless. Backed up with horror stories of "amputation for the fortunate; a horrific and not very quick way to die for the less fortunate!" While the symptoms and consequences are much the same, it doesn't cause sepsis (a systemic infection), which is treatable, there is no effective treatment for mineral oil in the blood-stream, it causes progressive failure of all organs until the heart eventually stops.

[Vic Evans]

The reverse is equally catastrophic but rarely injurious.
I well remember, as a young apprentice designer, being taken 'to site' to watch & witness a pressure test on a recently finished huge site welded oil storage tank.
The test went well & the engineers proceded to drain the tank of the test water. The only problem was that they forgot to remove the plug from the vent connection with the result that the tank noisely imploded & weeks of work had to be re-done.
The above reminds me of another oil tank catastrophe.
Many years later running my own company I was called to a local hotel where years before we had removed the steam boilers & converted the system with new low pressure hot water boilers running on 900 sec oil stored in two site welded tanks in the basement. The oil tank vents ran up about 60 ft on the hotels exterior.
On the day of 'the call' it was hissing down when a delivery was being made & the delivery driver was taking refuge in his cab after filling one tank & switching over the float operated Fillguard system to warn him when to stop filling.
When I arrived there were cars sliding & crashing on the sea front road on oil which had poured out of a vent & was being blown everywhere.
My investigation found that the grub screw on the changeover Filguard knob was loose & the driver, although turning the knob, hadn't actually changed tanks.
The upshot was that the rectangular tank converted itself to cylindrical having bust the internal stays.
Hell of a repair cost for the sake of one little screw & a driver, in a rush to keep dry, who didn't check he'd actually switched tanks.
Weeks later my company ripped out the oil boilers & replaced 'em with gas boilers.

[Vic Evans]

The reverse is equally catastrophic but rarely injurious.
I well remember, as a young apprentice designer, being taken 'to site' to watch & witness a pressure test on a recently finished huge site welded oil storage tank.
The test went well & the engineers proceded to drain the tank of the test water. The only problem was that they forgot to remove the plug from the vent connection with the result that the tank noisely imploded & weeks of work had to be re-done.
The above reminds me of another oil tank catastrophe.
Many years later running my own company I was called to a local hotel where years before we had removed the steam boilers & converted the system with new low pressure hot water boilers running on 900 sec oil stored in two site welded tanks in the basement. The oil tank vents ran up about 60 ft on the hotels exterior.
On the day of 'the call' it was hissing down when a delivery was being made & the delivery driver was taking refuge in his cab after filling one tank & switching over the float operated Fillguard system to warn him when to stop filling.
When I arrived there were cars sliding & crashing on the sea front road on oil which had poured out of a vent & was being blown everywhere.
My investigation found that the grub screw on the changeover Filguard knob was loose & the driver, although turning the knob, hadn't actually changed tanks.
The upshot was that the rectangular tank converted itself to cylindrical having bust the internal stays.
Hell of a repair cost for the sake of one little screw & a driver, in a rush to keep dry, who didn't check he'd actually switched tanks.
Weeks later my company ripped out the oil boilers & replaced 'em with gas boilers.

If anyone's interested I've just remembered it was 200 seconds oil not 900. No tank heating just outflow heaters to warm the oil on it's way to the burners.