DS21 BVH accumulator sphere

As David points out wih factory info letting the pressure off via your regulator, drop the car to low running and put a 12mm spanner on the bleed screw, with the nut, turn counter clockwise half a turn, you'll hear it hiss, hopefully you'll know this already. You can shake a bit more out by rotating the steering once left or right and back full then to straight. I mention that because I remember some serious citroenistes from NZ doing a lap of Oz who had to fix a leaking pipe and they put car on club hoist and went at it and got a good dose of eau de vert minerale mist all over them. Then they looked a tad surprised as it dawned on them what they had forgotten to do. Just saying 😂...
 
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Breaking News…. after removing coil, fuel pump, several spiral hydraulic lines and uttering some bad words I have managed to get at the return hose and the two bolts underneath and the single bolt on top and remove regulator. Foolishly thought getting the water hose from the expansion tank out of the way would make life easier but did not anticipate the radiator spilling itself out onto my garage floor… was expecting just the expansion tank contents but the siphon effect meant i had a flood and felt stupid as a result.

Sphere came off regulator ok and now have new sphere with new seal on and this afternoon will attempt the miracle of putting it all back together. the love/hate relationship continues.
 
jonf said:
Breaking News…. after removing coil, fuel pump, several spiral hydraulic lines and uttering some bad words I have managed to get at the return hose and the two bolts underneath and the single bolt on top and remove regulator. Foolishly thought getting the water hose from the expansion tank out of the way would make life easier but did not anticipate the radiator spilling itself out onto my garage floor… was expecting just the expansion tank contents but the siphon effect meant i had a flood and felt stupid as a result.

Sphere came off regulator ok and now have new sphere with new seal on and this afternoon will attempt the miracle of putting it all back together. the love/hate relationship continues.
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You've made it hard work on yourself. I've never removed coil, fuel pump and other nearby hydraulic lines (unless they are those attached to the regulator). Never removed the radiator hose either.

HOWEVER.... Removing the left wing makes life a whole heap easier for access and vision. It doesn't take very long either if you're practiced.
 
faulksy said:
There's a lot of noise online about how the pump should cycle every 30 seconds and anything below that is a problem. That might have been achievable when the cars were brand new but even the youngest are now 49 years old and the hydraulic units are all wearing out. The sheer number of places for internal and external leaks is staggering. I think manual 814 goes through all the testing proceedures but failing that 518 definitley does. Most of the on car tests involve inserting blanking plates into the seal flanges to cut off sections of the system or taking the hydraulic units off the car for bench testing.

I'd love to know how the LHD guys go with getting the accumulator out as they have the steering column and BVH brain also jammed into that space
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I've looked at that a number of times myself. The LHD brigade probably also looks at a RHD D and thinks "I'd never want to replace the starter motor on that - or the exhaust manifold...."
 
Jon - having done all that work, and whilst you're in there, check the engine mount.

In addition to all the obvious issues a sagging mount causes, it also makes it just that much harder to remove and refit the accumulator sphere.
 
PeterMol said:
But the writer has a bvh
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I realise that. I believe some of the replys were related to that "you can't unscrew the welded sphere off the regulator when it is in situ"?
You can if you jack the engine up a bit.
A couple of members senior to me have said the same thing.🤷‍♂️
 
thanx Nigel but replacing engine mounts would require getting engine sitting on a jack and now with car sunken to the floor that is no longer possible…. until i get the regulator and accumulator back in!!!! and i promise i’m not doing this again…..
 
The exhaust side engine mount is more likely to be at fault than the accumulator side. The extra heat kills them and the right side sphere.
I recall thinking the easiest way to remove and replace an accumulator sphere was to remove the regulator and sphere as one piece. The pipes were not that difficult to release and wriggle, though I seem to remember a pipe locating bracket inboard of the camshaft pulley.
 
Tuesday evening update

Job completed, swear jar is full, car is running again

I will spare everyone the moment by moment highlights.

but...............

after it started up for the first time, and rose to normal height, the pump was cutting in every thirty-five seconds.

I felt triumphant and almost superhuman.

I then shut the bonnet, opened the garage door, reversed out into the lane, turned the car around, noticed the steering was lighter and smoother than before, and reversed back into the garage so that the car was back in its usual position.

The pump was cycling every eight seconds and stayed that way for a few minutes until I turned it off and walked away in disgust.

Question:

is it just settling in?

Bleeding the steering and brakes and I just need to go for a drive?

or is the brake accumulator now suspect?

or have I got some other hydraulic problem previously undetected?

Reminder - there are no apparent leaks anywhere and the car drives wonderfully.

I am too tired now to even go for a five minute drive and my beloved somewhat reasonably expects me to re-enter the domestic bliss that predated this ghastly task.

Thanx to everyone who provided tips and encouragement. I learned a lot from your collective wisdom.
 
I realized in recreading what I wrote as advice made it sound like remove the bracket. It would have been more pertinent to point out check the bracket as they crack. Probably from being driven with dead accumulator spheres and causing the regulator to violently react whenever they surge with load. I patched up mine with some welds when discovering this little problem.
 
I know little about the intricacies of a BVH .. but the steering you will not need to bleed ( is that even possible ? ). The brakes may need to be bled as they are a dead ended system, and as well being a BVH there is the brake pressure controlled idle speed gadgetry.
I am sure others with closer experience will add more. There was available online an article written by an American expert on setting up a BVH ... as well as one about alternative hydraulic fluids that were technically up to specs. ( LHM being unobtainable ).
 
It's pretty common for that to happen. Painful as it is, you may have to check that the accumulator hasn't lost any nitrogen.

The front right brake caliper is bleed through the rear bleed on the centrifugal regualtor.

The front Left brake caliper is bled through the slow idle device on the carb.

The BVH brain is bled through the front bleed screw on the centrifugal regulator.

Steering will self bleed by turning lock to lock a couple of times.

Slacken the pressure reg bleed screw slightly, you need flow but not pressure to bleed.
 
fritzelhund said:
I know little about the intricacies of a BVH .. but the steering you will not need to bleed ( is that even possible ? ). The brakes may need to be bled as they are a dead ended system, and as well being a BVH there is the brake pressure controlled idle speed gadgetry.
I am sure others with closer experience will add more. There was available online an article written by an American expert on setting up a BVH ... as well as one about alternative hydraulic fluids that were technically up to specs. ( LHM being unobtainable ).
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Perhaps an aside here, but since taking the whole accumulator assy out is onerous enough it seems a bit masochistic to put it back down there in the abyss, on my (former) DS bvh I relocated it to the r.h front valance. This is a common enough modification I think? Easy painless access, and it could be recharged in situ. Of course, that sphere normally won't be serviced that often, but then again it is one of the things that gets left out just because it is a pain to get at. Anyway it is easily returned to the original setup if one strive for absolute originality.
 
thanx and yes if i was not chronically impatient compounded by a tendency towards laziness I would do that - it is how the SM is built and attending to the green blood circulation issues on my SM was always easier…. should never have sold it!!!!! but the $ went into restoring another car so i guess we can’t keep all the toys- can we?
 
hopefully the final chapter in this saga....

i just bled the regulator again.... and now have 18 - 20 seconds between pump cycles, and am satisfied with that.

After a short test drive around the neighbourhood, discovered that the intermittent electrical fault that made the taco wildly unreliable has now gone - must have been that wire I re-connected and tightened under the fuel pump? and after fixing the poor earth that meant no left turn indicators, I now have a fully functioning vaguely safe and reliable DS21 BVH again and am ready to conquer the world.

Again thanks to everyone who made positive suggestions and inspired me to have a crack and to do it all myself instead of taking it to the surgeons.
 
The regulator was fitted to the front of the gearbox on injection models. My BVH and the 5BVM are both like that - I seem to remember I made up a bracket and moved the regulator on one of them...
 
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