Thinking of using my abandoned LX AHC lines to create a onboard AIR System (1 Viewer)

[Edwardsrealtor]

I have been running my Non-AHC suspension for years now, but still have the pump/accumulator/globes and lines still connected. I am getting ready to install my onboard air system and am considering single air chucks at each wheel well vs a single hose coming directly from the air manifold. I understand there will be residual oil coming from the lines for sometime, but is there any reason I shouldn't do this? Is this a ridiculous idea? Thanks!

 

[Fsikalasinh]

I don't know the answer to your question but brilliant idea if it all goes well! I've been avoiding having to pull my lines for years now.

 

[Mike NXP]

Not a horrible idea , actually kind of cool sounding so far...on the flipside I wonder if it would be just as well to run flexible air line and maybe use the old lines as a means to zip / secure the new air line too.

I don't have an LX so not sure about the AHC lines. I suppose diameter of the line and overall condition is a factor to consider. Along with how possible it is to get to the line and fabricate a Schrader valve

 

[MongooseGA]

This is a really good idea. Looking forward to seeing what you come up with.

Just be aware that AHC lines look like and run close by some brake lines.

 

[baltistyle]

A good question might be, what was the reason that you removed the AHC in the beginning? Were there any leaks or any rust? Air is smaller than oil so if you had any leaks, I wouldn’t expect much from those lines. Additionally, I think you will get better performance out of new lines run to each wheel well because they will all be the same size and direct in flow and built for purpose. I would think it might even be cheaper to run new lines because you will need less custom fittings and MacGyvering.

 

[Edwardsrealtor]

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[Edwardsrealtor]

Not a horrible idea , actually kind of cool sounding so far...on the flipside I wonder if it would be just as well to run flexible air line and maybe use the old lines as a means to zip / secure the new air line too.

I don't have an LX so not sure about the AHC lines. I suppose diameter of the line and overall condition is a factor to consider. Along with how possible it is to get to the line and fabricate a Schrader valve

I work at a 4x4 shop and cannot say how many leaks I see from Air systems that have flexible hoses. This is what set my curiosity, hard plumbing like Hydraulic lines (AHC/BRAKES) can be more reliable in terms of being a tight system.

 

[Edwardsrealtor]

This is a really good idea. Looking forward to seeing what you come up with.

Just be aware that AHC lines look like and run close by some brake lines.

Copy That. I am considering using where they connect on the frame rail and bringing this to an ARB fitting in the are of the sliders. Final Mount place needs some time to consider.

 

[Edwardsrealtor]

A good question might be, what was the reason that you removed the AHC in the beginning? Were there any leaks or any rust? Air is smaller than oil so if you had any leaks, I wouldn’t expect much from those lines. Additionally, I think you will get better performance out of new lines run to each wheel well because they will all be the same size and direct in flow and built for purpose. I would think it might even be cheaper to run new lines because you will need less custom fittings and MacGyvering.

I appreciate the thought process here. Thankfully it wasn't an issue with leaks, rather was a continual globe issue and grew tired of the fight. I can see your reasoning for direct flow and hose sizing. This is one thing I need to explore further, is the different sizing at different parts of the system. my thoughts are if I have issues in using the AHC I wont be out of money other than the Fitting that would connect the accumulator fitting to my fitting.

 

[IndroCruise]

I have been running my Non-AHC suspension for years now, but still have the pump/accumulator/globes and lines still connected. I am getting ready to install my onboard air system and am considering single air chucks at each wheel well vs a single hose coming directly from the air manifold. I understand there will be residual oil coming from the lines for sometime, but is there any reason I shouldn't do this? Is this a ridiculous idea? Thanks!

Suggest as follows:

• Check internal diameter (and cross-sectional area) of AHC pipes versus pipe dimensions of the hose or pipe coming from a typical on-board compressor. Pressure loss (and therefore volume delivery of fluids -- air is a fluid) are VERY sensitive to cross-sectional area -- much, much more sensitive than losses due to pipe-length. (As an illustration, this is the ‘fluid mechanics’ reason that some Owners sometimes switch to a large diameter exhaust system but rarely change (shorten) the length of the exhaust pipe).
• Not meaning to rain on your parade, but IF it is worthwhile to proceed (which would be surprising), then first bypass the Control Valve Assembly (located on the inner side of the LHS chassis rail), and, bypass the long cylindrical Height Control Accumulator (located on the outer side of the LHS chassis rail). The reason is that the spring-loaded solenoid Levelling Valves within the Control Valve Assembly, and also, the Solenoid Valve within the Height Control Accumulator are ‘normally closed’ in your ‘dead’ (or any stationary) AHC/TEMS system. Fluid (including air) cannot pass unless these valves are open -- as and when controlled by a ‘live’ AHC/TEMS Electronic Control Unit (ECU). In this case, the AHC/TEMS functionality and the ECU has been disabled. So these Valves are closed and these devices would need to be bypassed if fluid flow is to be achieved along the full length of the AHC/TEMS pipelines for some other purpose.
• Late edit: Also suggest remove or bypass the Attenuator (located below the AHC Pump) to avoid possible interference and turbulence.

• In all modifications and connections, minimise frictional effects and turbulence (and pressure losses) due to sharp bends and fittings which interfere with smooth fluid flow.

More technical details and explanation can be found at these links:

Flow and Pressure in Pipes Explained — Practical Engineering - https://practical.engineering/blog/2021/4/6/flow-and-pressure-in-pipes-explained?rq=hydraulic

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