Crazy EAS bypass issue

[aussiebushman]

Bizarre situation!

The PO fitted Schrader valves leading independently to each corner air spring and supplied an ARB 12 volt compressor with the vehicle when he sold it to me. The original EAS pump, valve block and accumulator are still in place but are now bypassed.

I was having problems with the suspension dropping to the bump stops after only a few hours and km, despite pumping air into the system after each road trip. The fill points on the airsprings are very difficult to access, but liberal amounts of soapy water failed to locate any obvious air leaks.

For some reason beyond my simple bush brain, after pumping air into it again a couple of days ago THE SUSPENSION HAS STAYED UP! Mind you, I have yet to road test it and it may not stay that way.

Has anyone else had a similar situation and/or can offer any sensible suggestions?

[Graeme]

deleted

[PeterH]

When the EAS is working normally, the airbags (air springs) are mostly in the normal position.
This means the point where the airbags fold is the most stressed point, which over time can cause leaks while the bags are in that position.
The leaks can stop when used in off road, access, or highway heights, as the fold has moved due to the different heights and the leaks are effectively sealed up.
I'm guessing as you are manually inflating the EAS, the heights might be slightly different each time, so sometimes the leaks are there, other times not.
So you are not going crazy, I think this is most likely what is happening.
So the solution is probably new air bags, which should solve that issue.

Leaks can be hard to track down, but you are on the right track with the soapy water.
Another hard to spot leak point can be the diaphragm in the valve block, if you spray the EAS exhaust silencer with soapy water and see bubbles, that would point to a leaky diaphragm.

Hope that is of some help!

[aussiebushman]

Yours is the most sensible analysis imaginable!

The air springs are currently at maximum height and are not losing air at all. Because I live in the bush, I'm inclined to leave them that way and see what occurs when I take the vehicle for a drive.

The PO did supply a spare set of used air springs and I'll try to test them to see if they hold air. If so, it will be worth changing whichever current unit is leaking

Thanks again

Alan

[TonyC]

Hi Alen,

Are you saying there are 4 schrader valves, one for each corner?

Is the rest of the system, valve blocks, compressor and the like isolated from the air springs?

If so the for all 4 corners to drop it must be leaking at all 4 corners.

If all the original system and plumbing is in place, the the leak could be anywhere, but if all 4 corners are dropping I would guess the central valve block.

That said I'm only guessing, I've never had anything to do with a air sprung car, what I understand is from reading people's posts on mostly D 3/4s

Tony

[aussiebushman]

Hi Alen,

Are you saying there are 4 schrader valves, one for each corner?

Is the rest of the system, valve blocks, compressor and the like isolated from the air springs?

If so the for all 4 corners to drop it must be leaking at all 4 corners.

If all the original system and plumbing is in place, the the leak could be anywhere, but if all 4 corners are dropping I would guess the central valve block.

That said I'm only guessing, I've never had anything to do with a air sprung car, what I understand is from reading people's posts on mostly D 3/4s

Tony

The original syatem is still installed but bypassed by the additional lines and fill system so the original valve block seals are not the cause of the problem. There are four separate schraeder valves, one for each corner. They seem to operate independently altough there may be a interconnection I cannot see.

One corner seems to drop first so it is likely to be a defective airspring - see the recent post explaining how this occurs inermittently at at varying heights. Having read that explanation, I am now convinced that is the cause of the problem and the only solution will be to change at least one air spring, but probably all of them

[PeterH]

Another thing worth considering would be the self leveling function of the EAS.
If one spring is dropping, the vehicle will self level overnight and deflate the other springs, which would cause all 4 corners to drop.

If you swap the EAS relay under the passenger seat with a yellow relay, this will prevent the self leveling function from working.
The EAS will still work normally, just no self leveling, so if you leave it like that overnight, you will be able to determine if it is just the one spring dropping, as that corner will drop, but the others should stay as they are.

I usually have a yellow relay in my EAS to stop it dropping overnight, (also to put less load on the compressor), but you have to remember, in order to do any diagnostics on the EAS you will need to change the relays back over.
You might find it is just one spring dropping, it should be pretty obvious which one it is, sounds like you already know which one, but this will be a definite way to know for sure.

Hope that is of some help!

[aussiebushman]

Thanks again, Peter

I'll teke your advice and try the relay swap because it should help to identify which air spring is the culprit

Haven't driven the vehicle recenty and the suspension is still sitting at the high position.

[FANTOM P38]

If your system is bypassed you’ll be wasting your time.
You said each bag is inflated individually so only the bag or associated line can influence that corner.
I created a pressure check system with a t piece and pressure gauge that you can connect to any bag or tank to be 100% clear if it is leaking from that section to front near valve block. Simple & effective.
With eas system working it eliminates any of those parts then you can focus on valve block or sensors.
https://uploads.tapatalk-cdn.com/20250315/083b027a35f803a682561eb7e650ad79.jpg
Here is pic when testing air tank.

[aussiebushman]

If your system is bypassed you’ll be wasting your time.
You said each bag is inflated individually so only the bag or associated line can influence that corner.
I created a pressure check system with a t piece and pressure gauge that you can connect to any bag or tank to be 100% clear if it is leaking from that section to front near valve block. Simple & effective.
With eas system working it eliminates any of those parts then you can focus on valve block or sensors.
https://uploads.tapatalk-cdn.com/20250315/083b027a35f803a682561eb7e650ad79.jpg
Here is pic when testing air tank.

I have yet to determine whether the original EAS system has been "extended" or "bypassed" so until know that it is mostly guesswork.

This is getting too complicated for my simple bush brain so I have contacted Davis Motorworks for comments and a potential fix. For the sake of others having EAS problems. I'll update this post when I know more.

[aussiebushman]

Thoroughly ****ed off that three "expert" service shops have now refused to do even the most simple job of changing one or two air springs for me. I actually understand their reluctance due to the liklihood of a customer coming back to complain about an ongoing problem after paying for a repair. This would be the cheapest option

However, that is no help to me so I faced with:

a) Testing the "spare" airbags and using "Slime" or similar to seal any leak.
b) Then trying to find, then change the offending bag myself here in the bush
c) Paying the 2grand or so to rip out the EAS and fit coils

There are plenty of posts on various forums on the success or otherwise of using tyre sealants. They might work, but the bag needs to be removed to avoid getting the sealant into the lines as well as the bag. It is also unlikely to be a permanent solution

[loanrangie]

I would be determining if the added schrader valves are just teed or the lines are cut and the valve is the only means of keeping the bags inflated, like others have mention for all 4 corners to drop there has to be a common area thats leaking.
I replaced the front struts on my D3 last year the front started to drop overnight, i suspected the front valve block and it was only after raising up the front to put the axle stands under that i heard a woosh and found a split in a bag that was covered up in normal height and only leaked slowly over a week or so.

[aussiebushman]

I would be determining if the added schrader valves are just teed or the lines are cut and the valve is the only means of keeping the bags inflated, like others have mention for all 4 corners to drop there has to be a common area thats leaking.
I replaced the front struts on my D3 last year the front started to drop overnight, i suspected the front valve block and it was only after raising up the front to put the axle stands under that i heard a woosh and found a split in a bag that was covered up in normal height and only leaked slowly over a week or so.

Good idea. So far, I have only been under with soapy water when the vehicle is up on ramps, but not wheels jacked individually. It is very likely that the leak occurs only in some positions

[aussiebushman]

It is now evident that it is a rear bag leaking, because over the past week, one corner has dropped from maximum height to where the body is sitting on the tyre. The leak must be very slow to do that.

I found a Dunlop part number sticker attached to one of the spare (used) airbags so I now know which are the front and which are the rear units. I'll test the rear ones with compressed air in the hope of identifying any leak. I have purchased a can of Bostom brand tyre inflator/sealant and because the bag is on the bench, it can easily be rolled around, inflated and deflated to ensure the sealant gets to the leak. Only then will I swap the one on the vehicle for the spare.

Wish me luck please!

[aussiebushman]

It is now evident that it is a rear bag leaking, because over the past week, one corner has dropped from maximum height to where the body is sitting on the tyre. The leak must be very slow to do that.

I found a Dunlop part number sticker attached to one of the spare (used) airbags so I now know which are the front and which are the rear units. I'll test the rear ones with compressed air in the hope of identifying any leak.

Wish me luck please!


Examining the "spare" rear airsprings, there is NO evidence of splitting or damage and overall seem to be in good condition, so after a cleanup, I'm pretty sure they can be reused. Better still, my favorite mechanics at Tyre Team Goulburn changed the bags on another Land Rover just last week and have no hesitation about changing mine, so I have booked in to have this done next week.

The hard part will be getting the existing bage to hold air long enough to get me the 80km to Goulburn. I'm going to try this with about 30 psi all round, because higher than that it is like driving without any springs at all. Of course I'll take the 12V compressor with me so that I can top up on the way if necessary

We shall see!

[aussiebushman]

The EAS problem on my 2001 P38 has finally been resolved, thanks to Matt at Tyreteam Goulburn. However for the benefit od members, an explanation may help.

a) Despite others saying that an airspring change can be done at home,only a fool or desperado would attempt it. Two professionals, a hoist, supplementary lifting tools and special long nose pliers were deployed and even thenm the job took over an hour.

b) one rear shock absorber had failed so both rears were replaced - easy enough to do if you have the right tools

c) One rear Arnott airspring was obviously cracked,so both rear airsprings were replaced with the Dunlop ones supplied by the previous owner. That done, I drove off to get supplies, but quickly realised that one rear corner was bouncing off the tyre - as it had done before the work was done. I immediately returned to Tyreteam.

d) An airline indicated that one of the replacement airsprings was holding NO air at all so it was removed for inspection. The two sections of the bag had separated, because unlike the Arnott versions, there was NO metal ring securing the two parts, so any decent drop into a pothole was enough to break the seal - see attached picture.

Fortunately, one of the original Arnott bags that had been removed and replaced with the Dunlop was is reasonable condition so it was redeployed on the vehicle. The result has been exceptionally good. One the 80 km drive home over bad roads that included about 20 km of rutted and potholed gravel, the ride was quite good, I must say that the EAS is not as good as the coil suspension on my 91 Hiline, but it is acceprable.

The moral of this story is DON'T BUY DUNLOP AIR SPRINGS - the design is very poor. They may be acceptable for city and highway driving, but certainly NOT for country roads and/or bad gravel.

https://www.aulro.com/afvb/images/attach/jpg.gif

[prelude]

Agreed.

I run Arnott gen II's right now and have brand new gen III's on the shelve. Though one of my gen II's has leaked since day 1, it has been so inconsequential that I have left it for years like this. I'll be bringing the still good gen II front and rear (one each) as spares for my trip. The gen III's should be more comfortable than the gen II's. Do you happen to know which you have?

The big difference is that the gen III bags are non linear, so on highway mode they should sag to a broader part of the base resulting in a stiffer bounce and more highway worthy ride with less roll etc. Once you get to off road mode the base becomes thinner allowing more travel and more comfort/flex on the rough stuff. The added advantage is that on hard work the springs effectively become progressive. ie. the first part of travel is soft, hardening up once it reaches the end giving you some extra "room" before you hit the bump stops.

Cheers,
-P

[aussiebushman]

I spoke too soon, saying that the problem was fixed. There are minor airleaks where the distribution lines fit into the block housing the Schraeder valves and no amount of prodding or pushing will seal them effectively. The leak caus the suspension to drop overnight

Can anyone suggest a remedy?

New o-rings?
some kind of sealant?
Keep the front and back number plates and throw away everything in between?

[aussiebushman]

Got a decent compressor line onto the Schraeder valves and managed to punp the rear airsprings to around 60PSI before turning off the taps installed into these two air lines. That has effectively sealed off the part where the lines entered the block and where the most obvious leaks occurred. For sealing, I have read that Loktite will work though it will mean disassembling the connections

So now the arse of the vehicle is sitting very high. I took it for a test drive over a badly rutted track and unlike before, the vehicle rides reasonab;y well. I think the front airsprings need more air to provide greater clearance over the body/front wheels and to level the front vs rear. That should be doable even though there are no taps in those llnes


This at least progress of sorts and better than spending a couple of grand converting to coils

[prelude]

replacing the O-rings is a bit of a job but can be quite therapeutic for a couple of hours :) I have done 3 valve blocks in my time and it is not that bad.

I have found though that those push to seal fittings require quite some effort once they have been in place for a while to get out and inevitably you can damage one of the airlines. Not so much bend or break them but scratches develop on the surface which does not help in creating a proper seal. Running new airlines is quite a bit of work but you can do one at a time and (IIRC 6mm) airline is not that expensive.

Keep it up! you'll get it sorted :)

Cheers,
-P

[aussiebushman]

replacing the O-rings is a bit of a job but can be quite therapeutic for a couple of hours :) I have done 3 valve blocks in my time and it is not that bad.

I have found though that those push to seal fittings require quite some effort once they have been in place for a while to get out and inevitably you can damage one of the airlines. Not so much bend or break them but scratches develop on the surface which does not help in creating a proper seal. Running new airlines is quite a bit of work but you can do one at a time and (IIRC 6mm) airline is not that expensive.

Keep it up! you'll get it sorted :)

Cheers,
-P

Appreciate your advice.

The suspension has held up overnight so that is encouraging. The front is clear of the wheels but not by much so it does need more air in the two front airbags.
I'm not inclined to run new air lines for the reasons you explain but there IS room to trim and reseat them. For that I would use Loctite to helo them seal.

Thanks again - I'll keep at it

[aussiebushman]

Took the P38 to town today - 160 km round trip

After pumping up the front air springs to 150 psi, the all round clearance over the tyres was much improved and the vehicle sat level front to back. The ride was a bit bouncy, but tolerable , even over the rough, rutted gravel roads. Best of all, the suspension made the round trip without losing air

Sure, I could continue to adjust the pressures but like the old adage says "if it ain't broke, don't fix it"

[prelude]

That is good news :)

Now to get the EAS completely working automatically again? or are you going to take a brake from this little challenge for now.

Cheers,
-P

[aussiebushman]

That is good news :)

Now to get the EAS completely working automatically again? or are you going to take a brake from this little challenge for now.

Cheers,
-P

This vehicle is my backup for the 91 Hiline that was giving me trouble - now fixed. For that reason, the P38 rarely gets used more than once a month - if that. So no way am I going to spend big money on the EAS. It now works, even though it requires manual operation.

As said before - If it ain't broke, don't fix it