Repacement beads are cheap. Dry the old ones later if even you can be bothered.
Credit to wfooshee for explaining it, here, and it was actually obvious as soon as one got sight of a(ny) decent system explanation and observed some essentials were outright missing.

"In Industry..." drying compressed air is a major bizness, not left to a puny dessicant charge that was optimistically meant to be ignored for life. Oxygen separation plant, we even remove CO2 before starting the harder work.

Improvement is as easy as FIRST running the compressor output through a water separator (not the same animal as a dessicant chamber), only afterwards a dessicant chamber, BUT .. one designed to be serviced easily and often.
Blow-down valve needs to be at the water separator.

Nothing new in any of this. Larger versions had been on each of our five natural gas wells going back to War One.

In more appropriate sizes to this application the goods are dirt-common for shop air, any place as needs reasonably dry air where a "passive" solution is good enough. For the tiny volumes involved here, even "overkill" sizes are neither so bulky nor expensive that a place to live on the motorcar is all that hard to provide.

 

Do you have a source for the beads? I had thought of that but just baked mine in the oven to dry them out.
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Ebay sellers have them in sealed packets, with filter pads, each just right for one WABCO recharge.

https://www.ebay.com/itm/152579752055


Bead colour intensity indicates how 'dry' they are, so if a clear packet put by were to get cut while on your shelf, the damage would be obvious .

That said.. as the material is dirt-cheap if bought in larger quantities? Search on "orange silica gel beads", find even Walmart lists it - so we are paying for the convenience of not wasting it easily as much as for it coming pre-measured with the pads!

Other fish to electrocute, so I bought three for my two WABCO's + the rebuild kits I have stashed.

 

It is very common for the air springs to develop leaks in the top seal, which is a large rubber molding inside the air spring/shock absorber housing. You can see the upper surface of the top seal around the ECATS electrical connector and through a couple of holes in the air spring mounting plate. The top seal is integral to the assembly and non-replaceable. Some of us have experimented with techniques for re-sealing the top seal, but so far no permanent cost-effective method has been developed.

It is less common for leaks to develop in the air bladders except when a car has repeatedly been driven with the bladders underinflated.

Leaks in the top seal tend to open up more in cooler ambient temperatures, but can sometimes be detected with soapy water carefully spritzed around the top of the air spring (but not in the ECATS connector).

Leaks in the air bladder are difficult to find except by ear, if you can get the air spring to inflate.

Leaks in the air hoses are very uncommon except at the fittings that connect to the air springs.

Leaks are common at the small O-rings that seal the brass pressure-retention valves to the air spring. These can often be heard or detected with soapy water.

To get the fronts to inflate, try clearing all diagnostic trouble codes, preparing your leak detection techniques, run the engine for two minutes to allow the compressor to run its complete cycle, then shut off the engine and listen and use your soapy water.

Air hissing from inside a wheel well is usually a leaking air bladder.

Cheers,

Don

 

And if your hearing is as badly impaired as mine is, and/or it's hard to get a good ear close to the shock?

You may already have an 'open air' mic - close as a cell phone?

Or.. a set of 'contact' microphones - sold for electric guitar repair - is quite cheap on ebay.

Connect to any of many audio goodies that has an audio spectrum analyzer feature as part of its media suite (most laptops and smartphones) - or an Oscilloscope if you happen to have such, and you can put the mic right up close and personal where your ear won't fit, then "see" what you cannot "hear".

Better as well as cheaper than purchasing an ultrasonic leak detector gadget, as used for refirigerants and other compressed gas leak detections.

It is no more possible for a man to have "too many tools", than to get a wife to agree that, but those are optimized for far higher frequencies than we actually need, here. Unless you also DIY your air-con system?

 

Thanks for the tips.

All my air springs are new, my compressor is new, I have checked all connections with soapy water (top of each air springs, all connections on valve block in trunk). I listen in the trunk, while the compressor cycles off and on and I can hear things actuating in the valve block, cannot hear any air leaking. When I remove the air line connections at the top of each air spring, air is coming out of the hose, when the compressor is running.

The only thing left to have an issue is the valve block or the height sensors.


The height sensors give me readings on my iCarsoft i930 reader and the numbers change slightly up, on the front, while the compressor is on. I assume the sensors are working. Do they control more than the height number?

Is there a way to check the valve block, before I pay $300 +/- for another part that is not causing my problem?

 

Valve blocks don't last 'forever', nor cost very much, so a new one is an investment, not a waste.

Same again, height sensors. Cheap enough. If in doubt, swap it out.

China is Tata / JLR's largest market, so they have had a joint venture factory there for many years, already.
Alliexpress will find the parts we need at the prices the frugal Chinese pay.

About $36 to $58 for a solenoid valve block taste better than $300?

I mean.. it leaves money so one can still afford to go and eat sumthin' else a whole lot tastier, yah?

 

OK, thanks

 

I don't know if your iCarsoft can communicate with the valves or pressure sensor in the valve block but if so, you could monitor the signals. An acid test would be to loosen the air hose fittings at all four air springs and let about half of the air out of each spring. Then connect your scan tool and set it up to monitor the air suspension signals, then start the engine and watch what happens.

It still seems to me like you have a leak in one or both front air spring circuits. The most common leak points on new air spring/damper units are at the O-rings for the pressure-retention valves (the small brass cylinders that thread into the top of the air spring and to which the air hose fitting connects), and also at the air hose fittings themselves. If you did not replace the compression rings ("olives") or trim 5 mm off the ends of your air hoses when you installed the Arnott units, you may be losing air around the air hose fittings, although those leaks are usually the easiest to detect with soapy water (when the system is fully pressurized).

Also, you may need to recalibrate the ride height of your car. You will probably need the Jaguar Land Rover SDD system and at least a Mongoose clone cable. Search the forums for instructions on how to set up SDD on a laptop.

P.S. Your car is a factory project code X358. The X308 was the XJ designation from 1997 through 2003.

Cheers,

Don

 

What Don said.

Adding that the iCarsoft I930 mentioned as being in-use earlier in thread can read the data, but - AFAIK - can not do calibration.
Happy to be shewn otherwise if I have that wrong.

The iCarsoft V3 can do both. (I have both)

 

I do not feel I have a leak in the front air springs. I have checked with soapy water, numerous times. I had the front of the car bottomed out to start, then I put in two new front air springs, with the exact same result. I do not thing the new air springs have a defective connection. They come with the brand new fittings and when I took off the old fittings on the ends of the old air supply hoses, they were in very good condition and the ends were cut very square.

What Bill said, the iCarsoft I930 can read the pressure sensor and the damper voltage and when they are open and closed.

 

I think I recall that you can read the front ride height sensor signal, but have you checked it for signs of physical damage?

 

Thanks for that. I had not even tried it on the i930 once I had hands on the newer, 'sexier' V3!



To Don's point in re "sensors". I have enough of an electronics bench to ****-eyes the devices unto boredom. But it makes no sense to bother, given "nothing lasts forever". If Hall effect approaches immortality, surely the plastics do not.

Replacing them on age and gambling-odds alone, cheap as it has become, at least rolls a NEW set of dice.

As to air strut leaks? Wouldn't yah know it.. there is actually a US patent on repair of those?

https://patents.google.com/patent/US20070141253A1/en

No surprise, is it, that as with MOST patents... the technique is "obvious" enough.. but doesn't actually WORK!

 

I have already checked the front sensor. It looks in good shape, no visible damage. It is reporting an accurate level value for the front of the car (-72 mm) and the reading goes up 4 to 5 mm when the compressor comes on.

 

That's good news, then.

I haven't twigged to why they dropped to ONE front sensor and kept two rear, when it would seem bass ackwards, given driver as sole occupant at front... or not. Whilst rear was more likely to be in-balance, left-right, if not also more often empty.

Then again, I was 60 lbs heavier the year I acquired it than I am now, so the tilt is hardly noted..