P38A Eas what's what I need educating

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stuu

Well-Known Member
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Location
Aberdeenshire
So my compressor runs. Blue pipe off the bottom it blows my thumb off in a second good compressor I guess?

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Valve block can people tell me what's what i.e. Numbers and what they are?

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If I run the compressor in place air hisses out this pipe circled normal or not?

If I block it with my thumb it spits air out pfft pfft pfft out this thingy arrowed
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Is there anywhere with a dummy's guide?
 
All will happen as you describe running compressor direct from battery. If you run compressor by bridging relay 20 that will run compressor but also pull diaphragm solenoid to seal exhaust and send air through the pipe which should go to the storage tank. But it will only seal exhaust valve whilst you have your finger over end of pipe as it needs system pressure to seal it.

http://paulp38a.com/range-rover-p38/eas-valve-block-renew/
 
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Sorted I know what the system is what it does no clue how it works il get them on for my bed time research thanks :)
 
All will happen as you describe running compressor direct from battery. If you run compressor by bridging relay 20 that will run compressor but also pull diaphragm solenoid to seal exhaust and send air through the pipe which should go to the storage tank. But it will only seal exhaust valve whilst you have your finger over end of pipe as it needs system pressure to seal it.

http://paulp38a.com/range-rover-p38/eas-valve-block-renew/


Okay so eas gubbings plugged in the eas box
and relay 20 bridges. She still acts the same.
It still has the eas manual loom in do I need to unplug this to try?
 
Okay so eas gubbings plugged in the eas box
and relay 20 bridges. She still acts the same.
It still has the eas manual loom in do I need to unplug this to try?

I thought i explained. The air to seal the diaphragm comes from the pressure building as the tank is being filled. If you leave the pipe open to atmosphere you will never get pressure build up to seal it. As relay 20 is pulled it also powers the diaphragm solenoid valve, lifting it and causing pressurised air to go below the diaphragm to seal it against the valve block exhaust port. Bridge relay 20 block the pipe outlet with your finger you should get blow by as pressure builds. If air is still puffing past exhaust silencer diaphragm is knackered.
 
I thought i explained. The air to seal the diaphragm comes from the pressure building as the tank is being filled. If you leave the pipe open to atmosphere you will never get pressure build up to seal it. As relay 20 is pulled it also powers the diaphragm solenoid valve, lifting it and causing pressurised air to go below the diaphragm to seal it against the valve block exhaust port. Bridge relay 20 block the pipe outlet with your finger you should get blow by as pressure builds. If air is still puffing past exhaust silencer diaphragm is knackered.

You did explain well wammers
The same happened on the motor as it did just running off a battery.
I bridged relay 20
I didn't know if the was coil bypass loom would be stopping it closing the diaphragm.
 
You did explain well wammers
The same happened on the motor as it did just running off a battery.
I bridged relay 20
I didn't know if the was coil bypass loom would be stopping it closing the diaphragm.

Diaphragm solenoid is powered straight from relay 20, if the compressor runs the solenoid should be pulled. But to get it to seal exhaust you will have to put your finger over tank feed pipe #6 shown in your photo. To build pressure, air should start to blow past your finger, if it doesn't diaphragm will be duff.
 
Diaphragm solenoid is powered straight from relay 20, if the compressor runs the solenoid should be pulled. But to get it to seal exhaust you will have to put your finger over tank feed pipe #6 shown in your photo. To build pressure, air should start to blow past your finger, if it doesn't diaphragm will be duff.

I'm 100% with you now.
it does build a little pressure I can keep my thumb over it.

Very small amount comes out the smallest pipe of them all is that air tank feed yeah?

Exhaust still farts a little not as much but still does so looks like the diaphragm is duff
 
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A quick google but that seal nackerd would you say?

I see the complete o ring kits

I have 3boxes of assorted o rings at the workshop are the eas ones a special size or is it worth just getting a pre sized kit?
 
Get the proper set , I have lots of all sorted o rings for work and you can never get the right ones every time.
with the set you know they are right, you do not want to be trouble shooting the valve block.
 
View attachment 125050

A quick google but that seal nackerd would you say?

I see the complete o ring kits

I have 3boxes of assorted o rings at the workshop are the eas ones a special size or is it worth just getting a pre sized kit?

What are you trying to achieve? If you are thinking of returning car to air, by the looks of it you have a lot of work to do before you need to think about a working valve block.
 
That's where I'd like to get yeh

Unless you build a test rig trying to fault find the valve block is pretty pointless. Wait until you have everything else in place and use that as the test rig. Refurbing the valve block takes a couple of hours if everything else is in place.
 
Unless you build a test rig trying to fault find the valve block is pretty pointless. Wait until you have everything else in place and use that as the test rig. Refurbing the valve block takes a couple of hours if everything else is in place.
Oki dokes will do thanks wammers
 
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