I just bought an LR3 about 3 weeks ago and I love it, however it does seem to have some issues to sort out. Here is the rough rundown, 2006 LR3 SE V8 90k miles, HD package, cold weather package, Nav, hidden 9k warn winch. Now for the bits I need help with: Suspension seems to be settling after just a couple hours, after reading a lot it seems like it could be the valve block but maybe that is just a hopeful guess. Next thing is that the Compressor seems to run for quite a while, maybe 3 minutes, after startup. Have read about driers and wonder if that is a possibility or if my compressor is just getting tired. Suspension seems to raise and lower fine, raising is sometimes a bit slow but hard to say. I appreciate any input or troubleshooting suggestions.

Thanks,
Simeon

 

I pulled fuse 26? (EAS fuse) tonight to see how it settles by morning, it seemed like the front was settling more than the rear before. Are there other common places to check for leaks? Is there any way to check the valves other than just replacing them?

 

If it turns out that both front sides are dropping, then consider yourself lucky because the front valve block is likely your culprit and it is very easy to get to. It is located just behind the passenger side of the bumper and you can simply lift it upwards toward the top of the car and then pull toward the back of the car to remove. You can disassemble the valve block and clean the valves, replace O-rings, etc. There is a pretty good write up on it somewhere, but I can't remember where right now... Might just want to search for it.


If it looks like one particular wheel is dropping more than the rest, then you probably want to check the air lines from the valve block to the shock. You can spray with soap and water to see if you get bubbles anywhere in order to pinpoint your possible leak. If the leak is very slow, this likely won't work, but it's worth a shot. Apparently, from everything I've read, it is very rare for the airbags themselves to fail... leaks are usually found from the lines/connectors or the valve blocks getting dirty and not sealing/seating properly.


As far as the compressor running for a long time... I'd concentrate on fixing the leak first and see if it helps your compressor issue. If not, then I believe it could be that the desiccant in your dryer has deteriorated to the point where it has become a powder and is clogging up the lines (at least I think this is what happens). You might want to see if Jafir chimes in here because I was just asking him about this earlier today. If that turns out to be an issue, you can try to replace just the desiccant yourself or you can just buy a new dryer assembly for a little over $100 online.


Good luck. Let us know what the results are in the morning.

 

After removing the fuse last night, the front left dropped the most, almost 3", and the left rear dropped by almost 2", the front right dropped about 1.5", and the rear right dropped by about an inch.

After Sitting overnight:


Normal Ride Height:


Sound like a bad shock rather than a valve? Would the settle at the same rate if it was a valve or is that still a possibilty?

 

You have the right approach - read a lot and ask questions.

Pulling F26 is a good first start as that gets rid of a number of variables. It is almost like the gremlins play at night; pulling the fuse stops a lot of variables from getting into the equation.

I see you have a nice solid concrete driveway. Consider setting a pair of frame jacks under the front on either side as if you were going to remove both front tyres. Jack the 3 up a bit to take the weight off the tyres effectively removing the vehicle weight off the front air springs.

If there is leak in the front left air spring, it may be a very slow one, hence removing the weight might mean the rears stay at they were so to speak. The problem is to find where the problem is; most likely in the front somewhere but you want to discount the rear from the question.

If the rears look OK next morning, then next evening, just put a single frame jack under the left front and see what the results. Then same thing again, but the frame jack under the right front side.

The idea is to get the weight off the respective air springs. I also think there is some sort of tipping action going on when the left front deflates, (if that is what is happening), and that affects the other three corners; the selective application of the frame jacks may reduce that tendency.

 

Ok thanks for the troubleshooting ideas. If it as a small leak will it usually affect the whole system or just the bad component? I understand bad valve blocks will usually affect both front or both rears, but can a bad valve block affect just one corner? Or can a rear valve block some how have an impact on the front? There is a lot I don;t understand about the system still.

 

The link below will provide you with a fair bit of reading material as to how the system is supposed to work. I say supposed to, not to be confused with "how it works."

DISCO3.CO.UK Photo Gallery - LR3 Air Suspension fuse 35P ECU Manual Shut Off Switch

In theory, a bad front block valve should not effect the rear two air springs once the F26 fuse is pulled. It seems to however, but I think that is more because loads shift as one corner drops and it shows as other corners changing elevation.

Both the front and rear block valves each have three orifices. For each block valve, one orifice is for the left wheel, one for the right, and the third, the cross link valve, joins the left and right sides together when open or when leaking. The idea is that when say the left wheel drops in a hole, air flows out of the right spring to the left and pressures it up so as to reduce the tendency of the left side to drop down. When the cross valve leaks when parked, if there is a hole in the left air spring, air flows from the right side air spring and out the left side air spring.

If it is the front cross valve leaking and a front air spring also leaking, this leads to the front dropping; perhaps the two sides at different rates, but the rear is supposed to remain unaffected - that is the theory.

If neither side air spring has a leak, then a leaking cross valve is rarely noticed as the air has no where to escape to.

The front block valve is attached to the back side of the bumper sort of behind the right side fog light and can be accessed by removing the right front plastic fender liner, a bit of a pain I might add. The block valve can be removed without too much difficulty but you have to have four axle jacks under the frame as if you were changing all four wheels at the same time as the air system will be deflated.

Disassembly of the bock valve is possible as is replacement, maybe the best idea, once you decide the problem is probably there. Until then, you keep fooling around so to speak trying to determine the problem.

There is a good block diagram in the link below that you can download and print off.

DISCO3.CO.UK Photo Gallery - FASKIT Air Suspension Installation