P38 EAS Problem

In a nutshell

After a few hours the rear offside is on the bump stop.

Prior to providing feedback please read the following, it might help you to help me.


1 - Suspension never leaked, ever! Was always inflated in the morning, at the level I left it.
2 - Overhauled EAS valve block and compressor as vehicle is 1998 and 120k miles and thought an overhaul prior to it breaking was a good idea.
3 - After overhaul of valve block, rear both sides of suspension went to bump stops after 4/5 hours.
4 - Read some of the advice threads on this forum and subsequently rebuild the valve block and tested for leaks 6 times.....no leaks from valve block connectors (Tested with trusty fairy liquid and water)
5 - Now we are down to only the rear offside deflating to the bump stops, 'assuming' leak was via a valve that was tightened a little too tight to the valve block.

Here is the interesting bit...!
I am trying to divide and conquer why only the rear offside is leaking air.

6 - At the valve block I sealed off the offside rear (OSR) EAS valve (No 2 valve I believe) with a short length of 6mm tube and a push fit valve.
7 - I also trimmed the original OSR air pipe where it slots into the valve block (Just in case I damaged it during the valve block renovation) and fitted a push fit valve.
8 - I inflated the now isolated OSR air bag and allowed the EAS system to inflate the other three airbags and level off at high setting.
9 - Three days later the suspension at all corners is still at high setting. No leaks.

Now here is where I bang my head on the wall.
10 - I now connect the OSR rear air tube directly to the No 2 valve on the valve block. As the original air tube was trimmed I use a length of 6mm tube (Which has been heated and shaped so it does not put stress on the connections) and a Norgen steel bodied straight 6mm to 6mm coupling, which are reputed to be very reliable. The joints were checked for leaks several times and showed no signs of leakage whatsoever.

A few hours later the OSR is on the bump stops....:smash:

Now! I could run a replacement air line from the OSR to the valve block but! I already know the existing line is good.
The only obvious weak area is the straight connector and new short length of 6mm tube but it does not show any leaks.

Question
What can cause the OSR to drop to it's bump stop from within the valve block.
Bear in mind I have rebuilt the thing 6 times meticulously and have ensured the screws / bolts are not too tight but snug enough to nip up the new O rings....

I sincerely hope someone can shed light on this, due to it being the OSR valve it has meant stripping out the valve block completely each time.

Thanks.

it sounds as the OSR valve in the block is leaking in the block itself.

got to agree sounds like valve prob. Tip for future : If it aint broke.......

Strip the valve itself and look at the very thin O ring that seals the solenoid plunger cover to top of valve body. Seal it with a VERY small amount of silicone and reassemble. These O rings are not included in any O ring kits i have seen and never get changed.

wammers said:

Strip the valve itself and look at the very thin O ring that seals the solenoid plunger cover to top of valve body. Seal it with a VERY small amount of silicone and reassemble. These O rings are not included in any O ring kits i have seen and never get changed.

Click to expand...

Aha!
I did replace these O rings (Rangerovers.net kit includes them)
One must have not seated properly as they are very flimsy O rings.
I'll go and do that now, thanks very much for the direction

Mammoth said:

Aha!
I did replace these O rings (Rangerovers.net kit includes them)
One must have not seated properly as they are very flimsy O rings.
I'll go and do that now, thanks very much for the direction

Click to expand...

Also check seal on bottom of solenoid plunger and seat for damage. If seal is overly depressed stretch spring a little 2 or 3mm no more.

wammers said:

Also check seal on bottom of solenoid plunger and seat for damage. If seal is overly depressed stretch spring a little 2 or 3mm no more.

Click to expand...

Did this with the other solenoids where they were overly depressed at the seal on the end of the plunger, also cleaned a couple of the rubber plunger ends by running them in a figure of eight on 320 grit. (They sealed ok)
Might have missed this one......

Thanks for the additional info.

OSR solenoid plunger tip did have a deep depression in the rubber, was also slightly off centre.
The depression has been removed and the tip refitted with a little silicon grease to aid re-seating.
The plunger spring has been stretched a little....and a smear of silicon seal was used for the solenoid plunger O ring.

OSR still inflated after two hours...fingers crossed, I'll keep you posted.

Thanks for your help folks

Mammoth said:

OSR solenoid plunger tip did have a deep depression in the rubber, was also slightly off centre.
The depression has been removed and the tip refitted with a little silicon grease to aid re-seating.
The plunger spring has been stretched a little....and a smear of silicon seal was used for the solenoid plunger O ring.

OSR still inflated after two hours...fingers crossed, I'll keep you posted.

Thanks for your help folks

Click to expand...

Hopefully your mystery has been solved.It is often amazing how simple it is when an experienced expert like Wammers provides the knowledge

JohnP38 said:

Hopefully your mystery has been solved.It is often amazing how simple it is when an experienced expert like Wammers provides the knowledge

Click to expand...

For sure
and it is still up, so fingers crossed.

OSR suspension still leaking.

I've now removed the straight coupler and short air tube extension.
Stripped some of the protective wrap from around the air lines at the valve block end....
Plugged the shortened OSR air pipe directly into valve block.

Let see what happens.

If it deflates again I'll swap the OSR and NSR air lines, if the NSR deflates and the OSR remains inflated it will re-confirm it is the OSR solenoid (Now attached to the NSR) at which point I guess a new solenoid will be in order as 7 rebuilds is my limit....

If that does not work, springs it is.

OK, over to plan B, to remedy the air leak in the air suspension.

Just swapped the off side rear (OSR) and near side rear (NSR) valves from inside their respective solenoids. To be clear just the valves not the solenoids.
In theory because I did not dismantle the NSR (Working) valve the OSR suspension 'should' remain inflated.
I did rebuild 'again' the suspect OSR valve, which was originally in the OSR solenoid now swapped to the NSR solenoid.

In theory if anything goes diddly donk it should be the NSR suspension airbag, dropping to the bump stop due to a leaky valve block valve inside the solenoid....

Cheaper than springs at this point....!

Mammoth said:

OK, over to plan B, to remedy the air leak in the air suspension.

Just swapped the off side rear (OSR) and near side rear (NSR) valves from inside their respective solenoids. To be clear just the valves not the solenoids.
In theory because I did not dismantle the NSR (Working) valve the OSR suspension 'should' remain inflated.
I did rebuild 'again' the suspect OSR valve, which was originally in the OSR solenoid now swapped to the NSR solenoid.

In theory if anything goes diddly donk it should be the NSR suspension airbag, dropping to the bump stop due to a leaky valve block valve inside the solenoid....

Cheaper than springs at this point....!

Click to expand...

If you have no air bubbles (soapy water) coming from around the base of the OSR solenoid nor do you have any air coming out of the exhaust port. Unlikely because the OSR valve AND the exhaust valve would both need to be leaking. I don't think the problem is in your valve block. You have a leak either in the pipe from valve block to OSR bag it's connections or the bag itself. If the bag stayed up yesterday and is going down today you have a self sealing leak in the bag i would think.

wammers said:

If you have no air bubbles (soapy water) coming from around the base of the OSR solenoid nor do you have any air coming out of the exhaust port.

Click to expand...

To confirm, no bubbles and no air from ex port.

wammers said:

I don't think the problem is in your valve block. You have a leak either in the pipe from valve block to OSR bag it's connections or the bag itself.
If the bag stayed up yesterday and is going down today you have a self sealing leak in the bag i would think.

Click to expand...

My bad with the explanation...!! With one exception, the OSR bag has never stayed inflated since the valve block O ring replacement.
The exception was when I fitted a valve to the end of the OSR air pipe to isolate it from the valve block and blew it up manually, to check if I did indeed have an air leak between the OSR air bag and the OSR air line, at the point the air line plugs into the valve block.
Prior to air valve rebuild no leaks were present.

After swapping the valves (Including rebuilding the suspect valve, 'both rear air bags have remained inflated at highest setting for 5 hours....
Let's see how it sits in the morning!

Mammoth said:

To confirm, no bubbles and no air from ex port.



My bad with the explanation...!! With one exception, the OSR bag has never stayed inflated since the valve block O ring replacement.
The exception was when I fitted a valve to the end of the OSR air pipe to isolate it from the valve block and blew it up manually, to check if I did indeed have an air leak between the OSR air bag and the OSR air line, at the point the air line plugs into the valve block.
Prior to air valve rebuild no leaks were present.

After swapping the valves (Including rebuilding the suspect valve, 'both rear air bags have remained inflated at highest setting for 5 hours....
Let's see how it sits in the morning!

Click to expand...

Maybe newness sometimes things take time to settle down. Give it a while for everything to bed in.

Must have been the threat of a coil conversion.
Left on hi suspension setting yesterday afternoon and still sitting high and tight on hi-setting this morning
Only 8 valve block rebuilds later :violent:

Just the vertical adjust blend motor to sort, the lower power steering pump pipe oil drip, the front diff seal replacement, the lpg conversion to finish.....and so on.....:doh:

Mammoth said:

Must have been the threat of a coil conversion.
Left on hi suspension setting yesterday afternoon and still sitting high and tight on hi-setting this morning
Only 8 valve block rebuilds later :violent:

Just the vertical adjust blend motor to sort, the lower power steering pump pipe oil drip, the front diff seal replacement, the lpg conversion to finish.....and so on.....:doh:

Click to expand...

Looks like the newness has worn off then. Well done. If everyone was as patient as you we will have the coil makers going out of business soon.