I've done some searches, but can't find anything.

"An ounce of prevention beats a pound of cure...."
Is it possible to maintain the suspension system and so put off any failures?

If so, what can be done?

 

Hi haggis95,

What a great question! I don't yet know nearly as much about the suspension as I hope to, but here are some things that can be done as preemptive maintenance on the air suspension:

1. To reduce hard-to-diagnose electrical gremlins, help your battery stay healthy by keeping the battery power connections and grounds throughout the car clean and tight.

2. Keep your tires properly inflated to reduce stress on the air shocks/dampers.

3. If your car has done more than 50,000 miles or so (just to pick a number), the air compressor piston ring or seal is probably worn enough that the compressor is no longer charging the suspension as efficiently as it did when new. To help reduce stress on the compressor and air spring bladders, replace the piston ring with a new one from bagpipingandy. It's a very affordable way to restore the compressor to new performance, and the replacement process is easy for anyone with basic wrenching abilities, a socket set, and a set of Torx bits for your ratchet.

4. While you have the compressor out to replace the piston ring, carefully open the air dryer, pour the desiccant beads into a metal or glass pan, and place them in a 500F/260C oven overnight to reactivate the desiccant to a far greater degree than is ever achieved by the air backflow that is designed into the system. (Or, if you're crazy like I am, replace the desiccant with new beads).

5. Clean any corrosion and other gunk you find around the check valve/non-return valve and ensure that it seats properly.

6. I have not yet done this myself, but based on some of the symptoms reported, the next time I have our compressor out I will also open the exhaust valve and clean it of any corrosion and ensure the valve parts are moving freely, and likewise open the pressure relief valve and clean any corrosion there.

7. Replace all the Viton O-rings on the air hose fittings to reduce the possibility of future air leaks.

8. Use zero-residue electrical cleaner to clean all the air suspension electrical connectors and ensure they are firmly reseated and their wiring harnesses are undamaged. Here are the connections I can think of:

Air suspension relay socket and relay terminals (Relay 1 in the Front Power Distribution Fuse Box - disconnect the battery first as Pin 3 of the socket is always powered)
Compressor motor & exhaust valve
Compressor ground behind the front left headlight (brass brush plus spray)
CATS connectors at each shock/damper
Height sensors (At all 4 corners on early cars; 1 LH front & 2 rear on all other cars)
Air Suspension Control Module (ASM) (5 ASM connectors but only 4 are used on our '04)
ASM ground behind the back seat near the ASM (brass brush plus spray)
Valve block & Pressure Sensor in trunk/boot

9. Once I get a few other things sorted on our car, I intend to add a true water trap to the air suspension system, probably in the trunk/boot just ahead of the valve block to help protect it and the rest of the system from the humidity that gets past the air dryer and accumulates in the system over time and promotes corrision, sticky solenoid valves and other problems.

I don't yet know if there is anything that can be done to maintain the air spring bladders, other than maintaining the rest of the system so the bladders remain properly inflated, and never driving the car with an air spring deflated. Due to their inherent design and the stresses to which they are subjected in normal use, the bladders are going to fail eventually, and typically long before the shocks/dampers fail. I hope someday soon we will discover a source for DIY replacement bladders and the proper method for replacing them.

I'll look forward to additional ideas from others.

Cheers,

Don

 

Wow - what a thorough response! Thanks - this was exactly what I was looking for.

 

Since I can't add any expertise or experience to this thread I'm going to try expand and pull the info Don B has given me together:

1. I finally found a thread on the subject by googling bagpipeandy

Here it is: https://www.jaguarforums.com/forum/x...pressor-84990/

And one from the Audi forum which apparently uses the same complressor with a different mount:
Allroad Air Suspension Compressor strip & repair

Here's his ebay page bagpipingandy on eBay

 

Don B also mentioned replacing the "viton O rings" - and I had no idea what that meant.

I Googled it, and a thread started by Don B on here came up:

Here it is:

https://www.jaguarforums.com/forum/x...-115111/page2/

this is a photo from that thread:
https://www.jaguarforums.com/forum/a...p;d=1397293404

 

haggis95,

In case they are helpful, below are links to photos I took while rebuilding the air suspension compressor on our '04 XJR, with a new piston ring from bagpipingandy and new molecular sieve desiccant beads:

Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page


Cheers,


Don

 

Thanks Don B:

BTW what kind of store would you get dessicant beads from?

 

Here's an Arnotts video on how to remove the air compressor pump and install their rebuilt version. The steps will be the same though.

 

I purchased molecular sieve desiccant beads from Sorbent Systems (sorbentsystems.com) and McMaster-Carr (mcmaster.com). See my photo albums for more details. If I had it to do over again, I would order 1 pound each of 1/8" (3mm) and 1/16" (1.6mm) 4A molecular sieve beads, perhaps going together with another owner to split the combined beads since two pounds will do at least two compressors and probably more.

Cheers,

Don

 

Like you've noted above Don B, I've been reading various other threads where it seems that in order to avoid fault codes it's IMPERATIVE to maintain your battery to its optimum level - being able to crank the starter motor is not enough.