Air Suspension Leak - Requesting confirmation of reasoning

Marvinio

Greetings to everyone -
I own a 2008 L320 Supercharged model and am now attempting to resolve an enigmatic air suspension leak. All is OK while driving. After 48 hours in the garage, the back of the automobile gradually descends. After a duration of 4-5 days since its previous activation, the rear axle suspension remains devoid of air.

This began after the replacement of the two rear struts and airbags by a shop. I have been experiencing an elusive slow leak. Utilized soapy water and saw no indications of leaking at the air line connections on the struts. Could the valve block have malfunctioned? As only the rear is affected, the problem should be confined to the area posterior to the central air block. Both sides of the back descend simultaneously; it never seems unbalanced. This indicates that both rear axle bags are losing air uniformly. Does this imply that my rear valve block is probably the cause?

Thoughts are encouraged and valued

ranger

While I often work on the older P38, which has a far more intricate valve block, a buddy had an L320 that was experiencing a drop on one side in the back. He substituted the air spring and strut, nevertheless the issue persisted in the same spot. He is a mechanic who has a workshop equipped with a raise; so, one Sunday we visited and elevated the automobile using the lift. Removed the rear valve block, which is somewhat challenging due to the limited area for maneuvering a spanner to unscrew the unions, and placed it on the workbench. Disassembled it and substituted all the O-rings, applying a layer of silicone oil before to installation. It was refitted and has functioned flawlessly ever since. The O-rings were conventional sizes (at least in the UK) from his assortment, and we both concluded that he had squandered his funds by replacing the air spring, since the issue was with the valve block all along. The leaky O-ring may impact either one side or both, suggesting that you likely have the same issue and may have changed the springs without need.

Marvinio

Thank you, ranger! I will attempt to clean the back block and replace the o-rings next week. Amazon offered the o-ring kit for the L320 at an exceptional price of merely $35. I will update the discussion with my findings after I have completed the installation. Hopeful anticipation

angels84

I would reconstruct the air compressor and three valve blocks if they have remained untouched since the vehicle's inception. In my experience with the 2007 RRS SC, the failure of one side often precedes the subsequent failure of the others. At one time, I had deflation in the front, side, rear, and all four tires; however, since the compressor and valve were restored four years ago, the performance has been rather stable.

Have you attempted to manipulate all the hoses by pulling and pushing them? The hoses and electrical connection on the rear valve block are secure and difficult to attach or disengage.

norwaj

If both rear bags descend uniformly and there are no apparent leaks at the connections, it seems that the rear valve block may be the problem, perhaps allowing air to escape gradually. It may be advisable to replace it or conduct a test.

Marvinio

Update: At the last moment, I shifted from obtaining the o-ring kit and acquired a new (non-original equipment) rear valve block. Considering the cost of $50, I anticipated that this repair would be a simple plug-and-play task rather than a disassembly and repair endeavor.
That adversely affected me! The Rover restored power and elevated to its standard ride height; but, when raised to the off-road position, the valve block malfunctioned, resulting in a C1A33-01 (AF) error indicating a general failure in the rear left corner valve.

Due to the repair being quite frustrating because of the confined area for using a wrench, I opted to let the vehicle to remain still and see whether it would descend. It does not decline as rapidly as it did before. Currently, it takes around one week to fall, while it formerly reached the ground by days two or three. Currently, just the rear/right side is dropping, suggesting a potential loose or improperly fitted component on that side.

Any thoughts, comments, or feedback?

kinsella

Consider purchasing a high-quality OEM comparable valve block, such as the Vemo V48510005 or the genuine LR RVH000055. The inexpensive $50 valve block from Amazon is substandard. An alternative approach is to purchase a high-quality O-ring kit to fix your OEM valve block.

Marvinio

I am aware of that. Do not inquire as to why I succumbed to the notion of attempting to economize on this repair. I have spent more on repairs than the truck's worth; why would I consider a low-cost component to be beneficial? Amusing!
Original Equipment item has been ordered. Remain attentive.

kinsella

For your information, Vemo is the original equipment manufacturer sans the LR designation.