THIS is why you must remember to depressurise

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Stickyfinger
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THIS is why you must remember to depressurise

Post by Stickyfinger »

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

Alasdair
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Jay-Bruce
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Re: THIS is why you must remember to depressurise

Post by 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.
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Re: THIS is why you must remember to depressurise

Post by 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.
Anyone who has never made a mistake has never tried anything new. (Albert Einstein)
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Doo
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Re: THIS is why you must remember to depressurise

Post by 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 :oops:
Has anyone seen the plot? :?
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Stickyfinger
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Re: THIS is why you must remember to depressurise

Post by Stickyfinger »

I am most pleased people are watching this .....
Alasdair
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momag46
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Re: THIS is why you must remember to depressurise

Post by 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.
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royturbodiesel
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Re: THIS is why you must remember to depressurise

Post by 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.