P38, New EAS troubles

[Blanco]

So I had the EAS all working nicely, and then it let me down after a few weeks , there were some slow leaks but nothing I thought the system couldn't cope with, for example if unused for a couple of days the height would drop an inch  or so.

After getting the engine running again yesterday I thought I would look at it and see if the trouble could be.

Dusted off the home-made cable and fired up the free software from RSWsolutions.com which has served well in the past and attempted to reset the system.

As of the present moment I have not succeeded  in sorting anything out. (It has been a rubbish day actually, although the engine runs I now have at least three leaking injectors which I didn't have before!)

But there is a question I would like to ask if anyone knows why..... on starting even when running OK before the last malfunction, it would dump  air from the rear before refilling and then finding level. This undoubtedly wastes air and increases the workload on the compressor and I would like to stop it if possible. At present it just dumps the air and doesn't refill anything.

Also (OK two questions) it has failed twice now while on the move, once shortly after I bought it and the most recent occurrence, why on Earth does it dump the remaining air in the system under failure conditions, that just makes the situation 10 times worse at 60 or 70 miles an hour!

I have the EAS relay swopped out already for a 4 pin standard relay as per threads on that subject.(ie I dont think the auto-levelling function is the cause of it)  Airbags are now 2 years old and should still be OK. I have tried to find and repair leaks and there isn't anything major. Valve block had all new seals, and the compressor was working well when I last tested it but after it's latest trials that may no longer be the case. I seem to get a different fault list everytime I reset, but I'll have another crack at it maybe tomorrow afternoon and see if I can get a consensus of likely faults.

As ever all suggestions welcomed

 

[Escape]

You could have a leaking NRV, that will allow air to escape from the bags if the pressure in the tank is lower. Try running the compressor with the door open to build some pressure first, or better yet, fill the tank with a mains compressor (via the pipe to the top of the dryer).

It does make some sense for the system to try and level the car as soon as possible, because a level ride height will give better handling (and looks), provided there aren't any (big) leaks resulting in too low a ride height. If a hard fault occurs, getting the car on the bumpstops may not be the most comfortable option, but it is the safest. It will force the driver to slow down and avoid handling problems that could arise when one corner or one side is significantly lower than the other(s).

Filip

[Blanco]

Thanks Filip, on the NRV front I had two valve blocks and picked the best 3 from the 6 but the cones are marked on all of them although the seats seemed fine and the seals of course were new.  Has anyone sourced new NRV's I wonder?

Prior to trying it each time I have been charging the reservoir and setting all 4 corners at the standard height to save the compressor. If the storm isn't too bad tomorrow I might get a chance to tinker.

[Blanco]

Had a tinker with it this afternoon, found one pretty significant omission in the re-build, .......... forgot to put the spring back behind the diaphragm! sorted that and managed to reset the system. All good now except that the compressor is not pressuring up the system.  Probably it overheated the piston last time  They do seem to be very fragile the compressors.

[Escape]

You can check the compressor via the blue line. If you get pressure there, put the shop compressor on the blue line to check for leaks and correct operation.

One step at a time, you'll get there. 😉

Filip

[Blanco]

Well, I checked on the compressor using my finger and reckoned it was down on pressure, not very scientific but as I had only recently tested it that way when I was reasonably confident it was working well,  it was good enough.

ordered new seal and cylinder kit which turned up yesterday and went straight in last night. (You get quicker at it!). Fitted up this morning and the system was immediately happy, I didn't even have to get the laptop out, very happy.

Since the last post, the leak situation has been much improved, the front has stayed 100% leak free in the interim, the back settled slightly but that is probably 50/60 litres diesel, I haven't had to add air to any corner.

The only leak I haven't been able to trace is a slow leak from the reservoir, in the 10 days or so it has gone from about 85psi down to 40, I am hoping the system can live with that kind of leak, fingers crossed.

[Wrigglieryeback]

Hi everyone. I have a 1998 range rover. How do I find out what size the hoses are eg: 4mm or 6mm? I want set up an emergency connection as the EAS has a tendency to fail out of the blue. 

[Simon_CSK]

From memory they are 6mm. Know this cos the Disco 2 is 4mm and the P38 is bigger so has to get reducers to use the emergency inflation connectors.

 A wee tip. You don't actually need to T into the air lines. What I have done is bought 2  T pieces for the pipe and two inflation connectors and a length of 6mm pipe. If it fails I connect the t piece into the two front and the two rear pipes and connect them to two inflators. That keeps the suspension matched on both sides. This reduces the chances of an air leak.

[Blanco]

Yep 6mm, I am running with the relay out again  (I presume) because of the slow leak on the reservoir. I am going to run a whole new pipe to that to try and cure it once and for all. I see the viair quotes a 100% duty cycle, but I don't think it would fit in the box. I am sure that the trouble stems from the rigid small end of the con rod/piston assembly of the OE compressor, that generates too much movement and heat in the plastic piston ring. Any leak leads to an increase in the duty cycle that the compressor just can't handle, particularly if you want to make use of the low setting more than once in a blue moon to let the wife in and out more easily. I love it when it works but it is trying my patience .

[Simon_CSK]

1 hour ago, Blanco said:

Yep 6mm, I am running with the relay out again  (I presume) because of the slow leak on the reservoir. I am going to run a whole new pipe to that to try and cure it once and for all. I see the viair quotes a 100% duty cycle, but I don't think it would fit in the box. I am sure that the trouble stems from the rigid small end of the con rod/piston assembly of the OE compressor, that generates too much movement and heat in the plastic piston ring. Any leak leads to an increase in the duty cycle that the compressor just can't handle, particularly if you want to make use of the low setting more than once in a blue moon to let the wife in and out more easily. I love it when it works but it is trying my patience .

Stick with it the air suspension is great and I wouldn't put springs on a P38 as it wasn't designed that way.

It really is a simple system and you only have a compessor, reservoir, height sensors, airbags and associated pipework to go wrong.

[Escape]

18 hours ago, Simon_CSK said:

From memory they are 6mm. Know this cos the Disco 2 is 4mm and the P38 is bigger so has to get reducers to use the emergency inflation connectors.

 A wee tip. You don't actually need to T into the air lines. What I have done is bought 2  T pieces for the pipe and two inflation connectors and a length of 6mm pipe. If it fails I connect the t piece into the two front and the two rear pipes and connect them to two inflators. That keeps the suspension matched on both sides. This reduces the chances of an air leak.

That's false economy I fear. By connecting the bags side to side, you lose a lot of stability. The only thing keeping the body roll in check will be the front anti roll bar and the resistance of the rear trailing arms. Later LRs use this to increase articulation when offroading, and overcome the limitations of independant suspension. I'm gonna add a valve (or valves, I'll start with the front) to do the same in my P38, but even I will add a saftey so I can't accidentally use it on road as that would be properly dangerous. The price of an inflation connector isn't much more than a T-piece, so I just carry 4 inflators for emergency use.

The line to the tank can spring a leak where it crosses over the chassis. Or melt if you have an exhaust leak. Not too hard to replace and I can only echo the above, the system is pretty good and it's a real shame to convert to coils.

Filip

[Simon_CSK]

1 hour ago, Escape said:

That's false economy I fear. By connecting the bags side to side, you lose a lot of stability. The only thing keeping the body roll in check will be the front anti roll bar and the resistance of the rear trailing arms. Later LRs use this to increase articulation when offroading, and overcome the limitations of independant suspension. I'm gonna add a valve (or valves, I'll start with the front) to do the same in my P38, but even I will add a saftey so I can't accidentally use it on road as that would be properly dangerous. The price of an inflation connector isn't much more than a T-piece, so I just carry 4 inflators for emergency use.

The line to the tank can spring a leak where it crosses over the chassis. Or melt if you have an exhaust leak. Not too hard to replace and I can only echo the above, the system is pretty good and it's a real shame to convert to coils.

Filip

Filip

I only carry for emergency use and have 4 valves anyway so take your point. I may get some taps so I can close them off. By using one or two inflators you can ensure equal pressure across the axle meaning the car isn't sitting at the wrong angle.

[Blanco]

Here we go again, this time hopefully this will put an end to compressor trouble, the existing one seems to have trouble keeping the con rod connected to the motor, also found a leak to fix.... maybe this time it will last longer than a couple of weeks!😟