P38A Cycling EAS

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Hi All, a quick update.
Waiting to hear from Kurt and have bought a used valve block which I'm told is in good working order. This should be arriving in the next couple of days. My plan is to fit this but also buy nrvs from Kurt because it's possible (or very likely) that even if the new block works at first it may need a service soon. If all goes well I'll probably keep the old block for spares. Or I may have another go at repairing it so if I have more problems I have a quick replacement and can keep motoring. Repairs can then be done at leisure.
Cheers.
 
Hi All, a quick update.
Waiting to hear from Kurt and have bought a used valve block which I'm told is in good working order. This should be arriving in the next couple of days. My plan is to fit this but also buy nrvs from Kurt because it's possible (or very likely) that even if the new block works at first it may need a service soon. If all goes well I'll probably keep the old block for spares. Or I may have another go at repairing it so if I have more problems I have a quick replacement and can keep motoring. Repairs can then be done at leisure.
Cheers.

Have you managed to take a look at the suspect solenoid valves (I'm pretty sure it's the second from the rear on the top of the valve block, and even if I'm wrong it'll be the one underneath it) yet? Seriously, the spare valve block is a good move but you don't have to wait for it to arrive and you certainly don't have to overhaul it before you can use your car. Just take a real good look at the one you have already overhauled. In fact, don't even bother pulling the valve block at the moment. Just depressurise the system and remove that second from last valve on the top of the block. Leave the rest of the valve block in there while you take a good hard look at that one valve. If it you find a problem then fix that one valve and you're sorted... else yeah- you'll have to pull the valve block out of the car to check the orings under the collet and the valve underneath.

But go right ahead and do the top one right now. It's your good fortune that it's accessible without pulling the whole valve block.

I'd disconnect the battery before starting though..... you don't want to risk hard faulting the EAS ECU
 
Hi Darth, thanks for your encouragement. I have to admit I'm struggling with this. If you weren't so far away I'd drive over with a large bottle of malt and pick your brains.
A few days ago I sprayed the whole of the outside of the valve block with soapy water and the second solenoid from the rear (controlling the rear, left airbag) was leaking. I took it apart and found a slightly twisted o ring on the plunger sleve. when rectified things looked much better, but the rear bags still deflated slowly (over several days).
I then removed the block and looked at both lower solenoids and found no problems. I also looked again at the three nrvs and saw no problems but haven't yet bought new ones from Kurt.
At the moment, with the relay under the left seat removed, the two rear bags fall to the bumpstops over about four days. The front two remain inflated. I can see no leaks from the top of the valve block but have not yet had time to remove it and try and reconnect the air lines when out of the housing spray I can spray the underside.
If new nrvs might sort this slow air loss to both rear bags then it should be sorted when I have new ones. But if not, then I could get a new service kt and try again from scratch.
I still wonder about the small rubber inserts in the ends of the solenoid plungers. The cones they press down onto have left a significant indent and because of the play between the plunger and sleeve the indent is not exactly in the centre. I have obviously rotated them when dismantling and unless they close exactly into the indent they could possibly leak. But I have no idea where to get new inserts. I've thought of prising them out and replacing them the other way up but I might damage them when removing.
 
I've never had to replace the entire nonreturn valve- ever. Just replacing the oring around the tip has always worked for me. Do you have any reason to believe that the orings you fitted on the nonreturn valves when you overhauled your valve block might not be doing their job?

Did you check the 2 orings under the collets leading to the left rear airspring (I'm just asking- I'm paranoid about these from bitter, hair tearing, hysterical, wailing-and-gnashing-of-teeth experience)?

Finally- and this might be a problem where you are with your colder, drier climate although it's never affected me- if you're concerned about the plunger ends it MIGHT be worth waiting for your "new" valve block to arrive and just overhaul those two rear valves and swap them over to your existing valve block. If the rest of it ain't broke then don't fix it!

Alternatively, just try giving the plunger ends a little lube with a smear of silicon grease while waiting for the other valve block to arrive. This will help them seat properly and might even help condition them a little. You used to have the left rear deflate completely in an hour so now that it's taking 4 days tells me that you've definitely sorted out ONE problem but solving that has thrown light on another one, especially if it's now both rear airsprings that are deflating. A little free play between plunger and sleeve is normal, and an obvious indentation in the plunger end from the plastic nipple is also normal. Never been a problem for me out here but it might be worth giving em a quick clean with silicon spray and a microfibre cloth followed by aforesaid smear of silicon grease, especially if it means you don't have to cannibalise the incoming valve block and keep the whole thing as a spare.

Good luck, buddy. It might not seem it, but you're getting there!
 
Once again, many thanks for your ideas. I agree that one problem is solved which has probably highlighted another. Good to hear that an indent in the plunger end is normal. I have lceaned them vry well, and the cone on which they sit, but did not grease them because I wondered if that might help dirt sit on them causing a leak in the future. I might try some silicone grease though.
I'll see when the new block arrives and what time I have. I'm tempted just to fit it first and see if that brings an improvement. If so. I might be tempted to leave it in place. But I would like to find the problem with this block.

We'll see ....
 
no don’t go greasing bits in there. A small smear to help the rings seat then wipe down. You don’t want bits of anything circulating around in there.
As for NRVs do it once do it for good.
+1after cleaning everything in an ultrasonic bath I wouldn't want foreign bodies being blown around the airways,especially if the air drier dessacant is breaking up.;)
 
+1 on do NOT assemble the valve block with grease on anything. Also definitely check the desiccant if there's any sign of white powder in the block.

I'm doing a long term test to re-soften the plungers using Wintergreen Oil & IPA. They are definitely softer after 24 hours, so will be trying them in a valve block this weekend.

Regarding my test to soften the plunger ends, after 24-36 hours soaking all the plunger rubbers show definite signs of softening. I then cleaned them thoroughly, re-assembled the block, and did a 5 day pressure test on bench. Tank feed at 100psi & corners at 60psi with gauges on all five. It lost 4-5PSI on each corner, and 10psi on the tank feed, so all are sealing much better. All the other seals were replace a few weeks before, but this process has definitely improved the block's ability to hold air.
 
Once again, many thanks for your ideas. I agree that one problem is solved which has probably highlighted another. Good to hear that an indent in the plunger end is normal. I have lceaned them vry well, and the cone on which they sit, but did not grease them because I wondered if that might help dirt sit on them causing a leak in the future. I might try some silicone grease though.
I'll see when the new block arrives and what time I have. I'm tempted just to fit it first and see if that brings an improvement. If so. I might be tempted to leave it in place. But I would like to find the problem with this block.

We'll see ....

Good to know... just keep hacking at it methodically and you'll get there. This isn't rocket science.

Don't worry about the silicon grease either. We're talking a smear to help the plungers slip into place according to the indents when you reassemble, and the orings seat properly when you first repressurise (avoiding- for example- that twisted oring you found on your plunger stem), not a great big blob of it that's going to blow everywhere and gum everything up with dirt. I've re-rebuilt several valve blocks now and (not boasting here) a rebuilt block can go anything between 3 to 7 years, easily, and I've never had gummed up crud from the grease anywhere in the valve block when I go to re-rebuild a block that I'd already done a few years earlier. I've heard of some people using vaseline too... but I never have. I just don't like the idea of anything petroleum based coming into contact with the viton and rubber bits.

However, I like the idea of coming up with some way to condition the plunger ends and get them soft again. Maybe @pwood999 's wintergreen oil & IPA experimental cocktail might be worth watching if it doesn't cause the rubber to degrade over time while softening it in the short term.

I also like the idea of checking the desiccant. This CAN break down over time and send desiccant dust into the valve block, messing with its ability to seal. If you noticed any fine white grit in the diaphragm when you were rebuilding your valve block then it's definitely time to change the desiccant.

Good luck!
 
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Hello all,
Kurtjohnson10 is my hero. After trying and failing three times to improve two valve blocks with new o-rings (I've no idea why I failed) I bought a rebuilt one from Kurt. It works! There is still a slight leak on a couple of wheels but I guess that that is from one of my connections and is certainly not enough to worry about. Cheers to Kurt. :)

So now I move on to two other difficulties. The first is a dancing front end. My guess is height sensors or connections to them so if the rain ever stops I'll look into this.

The other is odd. The EAS pump continues pumping with the doors open - any door or all doors, including the tailgate. This started when I fitted a secondhand (not Kurt's) valve block and didn't happen with the original block. Any thought on where I should look to stop this happening? I'm not going to worry about this too because I can't see much of a problem - I assume it's safety related in that you don't really want the height to change when you're climbing into or loading the car.

Finally, thanks again to Kurt - if anyone is struggling with a valve block head over to him without hesitation.
 
The dancing can some times be caused by the heights not being with in two bits side to side.
And also worn sensors.
If you have access to a Nanocom, you can watch the sensors as they sit in real time. Any jumping readings at any height then the track is worn and it's time to swop them for a new pair.
The pump will run with the doors/boot open or shut. ;)
 
Fixed that for you!:p:p:p:p:p;)
tenor.gif
 
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