All Things V6...

[DHallworth]

Well I decided I'd recharge all the spheres on the CX this weekend so I got myself a cylinder of Nitrogen from Air Products this afternoon.



One side of the regulator shows the pressure in the bottle, the other side shows it in the sphere:



To pressurise the sphere you open the big black tap on the bottom of the regulator that you can see in the first picture. This lets the gas into the sphere. The instructions say you add 3 bar to the pressure required. When you've reached the desired pressure you wait for 1 minute for the sphere to be pressurised. Once a minute it up you close the black tap. I was recharging an accumulator which should be 62 bar so I topped the sphere up to 65 bar.



The brass screw on the side is used to reduce the pressure in the sphere to the correct level:



Once you've set the pressure you tighten the valve onto the sphere and release the charging rig and put a green cap over the end of the sphere.



The instructions for the recharging rig state "NEVER RECHARGE A SPHERE WITH LESS THEN 15 BAR OF PRESSURE". The accumulator that came off the CX was reading 8 bar so I threw it away. I went through the massive pile of old spheres I've got and found the accumulator sphere I took off my Xantia Activa last year. When testing that it was at 45 bar. After checking, all accumulator spheres are the same so I recharged that one and fitted it back to the CX.

The pump now sounds much happier and the regulator is now ticking every 30 seconds again rather then every 3 seconds before. Will try and get the rest of the CX spheres done this weekend and then the two XM's and Xantia at some point. I noticed that one of my old spheres in a box has a recharging plug on it. The instructions say they are only to be used once though so not sure if it's worth recovering or not.

At first I couldn't get the sphere to take gas. However on closer inspection the valves aren't actually valves, they are more akin to bungs. There's no direct path through them for the gas. Reading the instructions that came with the rig says that you fit the "valve" to the sphere without tightening it, then you place the recharging tool on top of the valve and gently tighten it down onto the sphere. There's an o-ring in the charging rig that creates a seal around the sphere. When you open the regulator there is a seal created around the sphere as the valve pulls away from the sphere and the rig is pulled towards the sphere. You can then hear the gas flowing into the sphere. Once the sphere has gas in it you tighten the screw on the back of the recharging rig and that tightens the valve onto the sphere which creates the seal and stops the gas escaping.

As these are just bungs, there's no real reason that I can't make more of these on the lathe when I have time.

David.

[CitroJim]

Brilliant you could have the startings of a nice side-line there David...

Always a demand for sphere recharging services

[superloopy]

What make are those valves David? Bigger than the the valprex (?).

Sent from my LG-D855 using Tapatalk

[DHallworth]

The problem with offering the service is that I can't get many of the valves!

I managed to buy 38 of them on eBay, upon closer inspection there was an o-ring missing from one of the valves so that ones a dud unless I can source an o-ring for it. They're small green ones that are a little bigger then the ones you remove from the spheres.

With the CX, 2 XM's and the Activa I've worked it out that I need 31 valves for my own cars so I've not got enough spares to do a complete car even.

Mike, those are genuine Citroen valves.

The CX threw a spanner in the works last night... It would start but would instantly cut out. I went and got a new fuel filter for it this morning and fitted that but it didn't make any difference. I then got the workshop manual out and checked the resistance of the temperature sensor against what the book said and found that the readings were wrong. Thankfully Euro Car Parts had a new temperature sensor in stock for £19.99. They've got a 20% sale on this weekend so I got it for £15.99. After fitting that she's running perfectly again and the hydraulic pump sounds much, much happier now it's got a pressurised accumulator on it!

David.

[Stickyfinger]

Glad its running again David

[DHallworth]

A bit more progress today... I've also officially declared that I'm a hoarder...

The accumulator sphere on the CX was down at 8 bar so couldn't be recharged. I thought it was the Activa accumulator I recharged for it yesterday, it wasn't, it was the XM's old accumulator. Tonight, I removed the brake accumulator from the CX tonight, it's held in place by a jubilee clip around a bracket on the car. The sphere was utterly solid on the block so I had to remove it from the car. One of the 4.5mm pipes wouldn't undo and the flare rounded so I had to cut it off and remove it in the vice. I then used a hammer and a bolster to break the seal on the sphere. When pressure testing the sphere it had ruptured internally.

Whilst having a rummage around the shed I found a box with 10 old spheres in it so those are the Activa's old spheres. I dug out the accumulator and found it was at 45 bar so I recharged that and fitted it to the CX. The difference in the behaviour of the hydraulic pump now it's got 2 good accumulators on it is massive.

Once these two were done I moved onto the front spheres. Whilst removing the bung from the top of the sphere with a pair of stilsons the sphere on the passenger side loosened from the strut top so I removed the sphere and pressure tested it. The front sphere was at 55 bar and should have been at 75 bar so I recharged that one, the drivers side sphere I did in situ without removing.



The rear spheres can't be done in situ as there's no room for the tool to seal around the charging port on the sphere. Removing the rear spheres looks like a whole lot of fun



Will have a look at removing them from the car tomorrow and then that's all the spheres recharged. After that and once the welding has been done the car is finished. The only thing it then needs prior to hitting the tarmac properly is a set of tyres. That's going to be painful.

David.

[CitroJim]

What a lot of adventures David!

Good stuff and excellent reading

I always understood the Pleiades sphere tool was so designed to facilitate CX sphere removal and it's more a stroke of luck it happens to work so well on other Hydraulic Citroens...

[DHallworth]

When I got the CX I set a goal of having it ready for the road for the 1st July. The car itself is finished, the spheres are done, pipes are done, all I need is the welding done. There's a local guy who is coming to do it but he hasn't said when yet. Reckons it'll take him an hour to do. He's going to cut the rotten area out, make a patch and then weld the patch in.

I just wish he'd get a move on!!

I did however have it out for a quick run up the lane that we live on tonight and she's running really well, when you floor it in 2nd the bloody thing flies. It's a cracking car!

More updates when the welding is done hopefully.

David.

[Mandrake]

Shame about the welding delay David, but it sounds like everything else is ready.

How did you get on with removing the rear suspension cylinders to regas the rear spheres ? And how does it ride on your bumpy lane past the house ? I seem to remember that it is quite bumpy and potholed in places, and if working well the CX should soak it up rather nicely.

Glad to hear the engine seems to be running well too, hopefully the turbo is in good nick with plenty of life left in it - the only turbo car I've owned (admittedly a Daihatsu Charade ) gave me no end of turbo problems (blew out the exhaust gasket twice due to slightly warped exhaust header flanges flanges and later the turbo seized up and needed overhauling as well) so I've always been a tiny bit wary of turbo engines in general and have not owned one since. Does it have a turbo timer ?

[DHallworth]

How did you get on with removing the rear suspension cylinders to regas the rear spheres ?

I didn't... I needed it off the ramp today so I'll attempt them when it goes back on for the welding to be done.

And how does it ride on your bumpy lane past the house ?

I didn't pick up much speed today, but it did ride very well.

Glad to hear the engine seems to be running well too, hopefully the turbo is in good nick with plenty of life left in it

It seems to run very well, I've changed the oil in it once and will do it again before I start using it regularly. It was a but spluttery when I first started to ask it for power but that cleared very quickly and when I planted it in 2nd it came on boost very aggressively and took off. It surprised me how quick it actually is!!

David.

[DHallworth]

The CX has presented me with a problem today...



It starts up and will run ok for a few seconds, then splutter, then die. If you even try and rev it at all during it's tantrum it dies instantly.

When I took it for a blast up the lane it would violently bunny hop. Dipping the clutch and changing gear was enough to get rid of it briefly. However when coasting down a long hill in overrun to come to a t junction all appeared ok, but when I dipped the clutch at the bottom of the hill it cut out.

After a restart it was ok for a hundred yards of so before it bunny hopped again. When I dipped the clutch this time it cut out. After restarting it this time it ran for a second and cut out straight away, after several attempts to get it running again it eventually caught and I was able to turn it around and go back towards home.

When going down the hill the other way, all appeared ok but when I went back on the throttle there was nothing there. After a second it kicked and ran ok down to the house. It'll idle without problem once it's started but when asking it for power it seems to bunny hop violently. It doesn't do it all the time either.

It's had fresh fuel, new fuel filter, new plugs, and when it wouldn't start last weekend I fitted a new temperature sensor. After fitting this it started first time!

Other then changing things now as a process of elimination I'm not really sure what else to do.

Plug leads, coils, crank sensor etc. are the next on the hit list I guess. Anybody got any suggestions?

David.

[elma]

I wonder if your fuel pumps getting cut off by the relay.
http://holdenpaedia.oldholden.com/Tachometric_Relay

[Mandrake]

Hi David,

If you start it from completely cold and just let it idle, how long does it idle for until it splutters and dies ? About a minute or so ? Or do you have to rev it up to 2000 or so for a couple of minutes before problems occur ?

I haven't checked the service manual to see if it even has one yet (I assume it does) but my first guess on very limited information is that the oxygen sensor is faulty, maybe shorted. I also don't know whether it might be a heated oxygen sensor or one that relies entirely on exhaust heat - the 80's was around the time when heated oxygen sensors were only just starting to come in.

It appeared to idle perfectly initially in your video then started to struggle as if it was either running very lean or very rich. An oxygen sensor that was shorted to ground would cause it to run OK initially when the ECU is in open loop mode but it would then start trying to run very rich as soon as it started using the sensor and probably drown itself.

Oxygen sensor also fits in with what you reported during driving the other day where it you said it was "sputtery" when you first started to accelerate but then went OK when you floored it. Flooring it would switch to open loop mode and ignore the oxygen sensor.

Of course there's no Lexia support on a CX so it will have to be diagnosed the good old fashioned way.

A couple of things you can try to confirm an oxygen sensor problem -

1) Try unplugging the oxygen sensor. Depending on how smart the ECU is it should realise that the oxygen sensor is absent and fall back to running in open loop mode all the time. (ECU's this old might not be this clever however) If it does this, then the engine should run normally without any sputtering or stalling, although it will run a little richer than normal so you don't want to run it like this for a long time and it won't pass the emissions test like this either. But if you can drive it up and down the road a couple of times with no sputtering with it disconnected its almost certainly faulty.

2) Try to backprobe the oxygen sensor signal so you can get a volt meter or scope connected to it while it is still connected and the engine is idling so you can look for the characteristic low/high switching - remember we did exactly this on your mates 205 as we discovered the Lexia was telling lies about the oxygen sensor voltage! As well as switching low/high during idle it should go high when you briefly floor the throttle and then low on the overrun. If you have the right gear and can get connected properly its fairly easy to diagnose this way.

If I get a chance today I'll browse the CX service manual I download to try to get more familiar with the injection system on this engine to see if I have any other suggestions. Other possible candidates like MAP sensor and TPS can also be checked fairly easily with a volt meter or scope.

[xantia_v6]

A 1988 car probably doesn't have an oxygen sensor, as 98 octane fuel in the UK still contained lead at that time.

Add ignition amplifier and MAP sensor to your list of candidates.

Definitely change the fuel filter...

[Mandrake]

And Re James's fuel pump suggestion - if you have a fuel pressure gauge T it in and monitor the fuel pressure when it is running ok and also when it is sputtering and dying - you'll soon see if it is a fuel pressure problem or not.

My hunch is that it isn't but it's an easy test to do that will help narrow down where the problem is.