Wierd EAS compressor problem . . .

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odyssey

Active Member
Posts
364
Location
Derbyshire
EAS is working fine, but over the last couple of days it occasionaly makes a heavy vibration when the pump runs. Sometimes it's quiet as normal then the next time it starts it rumbles so you can hear it in the car. Seems to be producing air as the car goes up and down as quickly as normal. Pulled the pump and cleaned the reed valves and piston/cylinder, piston seal probably will need replacing soon but for the moment OK.

Anyway - the question - should there be any movement of the piston counterweight relative to the motor output shaft? The weight seems to turn on the shaft by about 15 degrees. Bearings and end bush all seem fine, BUT I can't loosen the grub screw that holds the weight on the shaft. What size is it - 3.5mm? Haven't got a 3.5mm key, or is it imperial? If it locks onto a flat on the shaft and has loosened, maybe this would cause the vibration . . .
Any thoughts gratefully received, before I go and buy new allen keys.

Alastair
 
I think the key is 3.5mm, Wammers would know for certain, when I did mine I just went through my box of keys until I found the right one so not certain of the actual size.
If it's loose on the shaft it will certainly vibrate.
 
1/8" Allen screw. Seats on a flat on motor shaft. Make sure you have Allen key fully engaged and use steady pressure to undo. Make sure flat is lined up on reassembly.
 
Many thanks gentlemen.
If I'm taking it apart again I may as well do the seals.
I'll order a seal kit - any recommendation on which is the best, I seem to remember there were some that were below par. Only need the teflon seal and 2 O rings, everything else is fine & dandy.

In passing, is worth lubricating the cylinder/piston? - if so with what?

THX Alastair
 
odyssey said:
Many thanks gentlemen.
If I'm taking it apart again I may as well do the seals.
I'll order a seal kit - any recommendation on which is the best, I seem to remember there were some that were below par. Only need the teflon seal and 2 O rings, everything else is fine & dandy.

In passing, is worth lubricating the cylinder/piston? - if so with what?

THX Alastair
Click to expand...

Do NOT lubricate cylinder or piston.
 
Don't no but had my compressor of a couple of weeks ago and it had 3 rubber sort of washers under the metal ones don't no I've that mat help it stop vibrating to much
 
After you sort the compressor . . . . . raise the entire plastic EAS housing 5mm or so from the inner wing using thick washers under each corner bolt. The bottom of the plastic tends to droop and vibrate on the inner wing. My guess is engine bay heat allows the PVC to swell & droop !

Pete
 
pwood999 said:
After you sort the compressor . . . . . raise the entire plastic EAS housing 5mm or so from the inner wing using thick washers under each corner bolt. The bottom of the plastic tends to droop and vibrate on the inner wing. My guess is engine bay heat allows the PVC to swell & droop !

Pete
Click to expand...
Or carefully re-shape the inner wing with a lump hammer to give clearance:D
 
No droop here :).

I can get a spanner in between the box and the wing . . .

Incidentally, I find it very intriguing how threads can drift off topic into weird (spelt it correctly this time - you can't edit thread titles) and wonderful (and rude - you know who you are) areas.

It's a bit like that pub game where you trace back the conversations and how each topic developed from the previous one - discussion geneology but here you don't have to remember, it's all written down!

Thanks all for the thoughts - and less so for some of the imagery . . .

A
 
Last edited:
UPDATE - finally got an allen key that fits - 3/32" and removed the counterweight and piston. Blue loctite on grub screw threads, very tight, but moved eventually.

New seal arrived from these people:- RANGE ROVER P38 EAS AIR SUSPENSION COMPRESSOR PUMP MOTOR SEAL LINER U2 | eBay, O rings fine, but seal seems to be a different type of material to the old one, it's whiter and slightly translucent, listing claims it's teflon.

Anyway it was very tight - and almost impossible to get it into the cylinder, in spite of Wammers dire warning about not lubricating it, I used a little silicone oil so it would at least move in the cylinder. (Story Wilson's video guide mentions using petroleum jelly if it's hard to get it in [don't even go there tomcat59alan].)

Put it all back together and it ran, but slower than before, and then it got slower, and slower, until after about a minute it all but stalled - one rev every 10 secs or so. Motor body got almost too hot to touch. Took it back out and apart once it had cooled.
Think maybe as it ran the remaining lube dried and there was just too much friction for the motor to turn it. Pic attached shows the smooth wear marks on the edge of the seal, but more pronounced on the shoulder, where it rests on the top of the piston rather than the lip. Not sure how relevant this is . . .
Also the retaining ring also stands slightly proud of the piston even though I drifted it down with a large socket. Pic attached. Wondered if it may be in danger of hitting the pump head as there's the cut out for the reed valve retaining screw so there may be very little tolerance.
I'll try again using petroleum jelly to see if it 'runs in', but before that - a question.

How does the motor shaft come out of the bearing in the pump body. I decided to strip the pump right down to clean it properly, took the motor end plate off and of course the brushes sprang 'in' and will be a hell of a fiddle to hold open to get the commutator back in place.

Tried tapping the end of the shaft but it doesn't want to move and I didn't want to damage the end of the shaft so the counterweight won't fit back onto it. Has anyone split the armature from the bearing? I've not got a puller the right size.

Sorry for the long post, any info will be most gratefully received.

Alastair
 

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I've refurbed a few of these pumps and never had to use lubricant to get the piston back in. This wouldn't be the first time that someone has tried, and failed, to improve on the original. (Hands up those who remember the Dutch kits)
Try 'original_landyair' on ebay for parts. Under his previous name of 'symilise' he has always been my preferred supplier and every refurb has worked first time.
 
odyssey said:
UPDATE - finally got an allen key that fits - 3/32" and removed the counterweight and piston. Blue loctite on grub screw threads, very tight, but moved eventually.

New seal arrived from these people:- RANGE ROVER P38 EAS AIR SUSPENSION COMPRESSOR PUMP MOTOR SEAL LINER U2 | eBay, O rings fine, but seal seems to be a different type of material to the old one, it's whiter and slightly translucent, listing claims it's teflon.

Anyway it was very tight - and almost impossible to get it into the cylinder, in spite of Wammers dire warning about not lubricating it, I used a little silicone oil so it would at least move in the cylinder. (Story Wilson's video guide mentions using petroleum jelly if it's hard to get it in [don't even go there tomcat59alan].)

Put it all back together and it ran, but slower than before, and then it got slower, and slower, until after about a minute it all but stalled - one rev every 10 secs or so. Motor body got almost too hot to touch. Took it back out and apart once it had cooled.
Think maybe as it ran the remaining lube dried and there was just too much friction for the motor to turn it. Pic attached shows the smooth wear marks on the edge of the seal, but more pronounced on the shoulder, where it rests on the top of the piston rather than the lip. Not sure how relevant this is . . .
Also the retaining ring also stands slightly proud of the piston even though I drifted it down with a large socket. Pic attached. Wondered if it may be in danger of hitting the pump head as there's the cut out for the reed valve retaining screw so there may be very little tolerance.
I'll try again using petroleum jelly to see if it 'runs in', but before that - a question.

How does the motor shaft come out of the bearing in the pump body. I decided to strip the pump right down to clean it properly, took the motor end plate off and of course the brushes sprang 'in' and will be a hell of a fiddle to hold open to get the commutator back in place.

Tried tapping the end of the shaft but it doesn't want to move and I didn't want to damage the end of the shaft so the counterweight won't fit back onto it. Has anyone split the armature from the bearing? I've not got a puller the right size.

Sorry for the long post, any info will be most gratefully received.

Alastair
Click to expand...

You have got yourself in trouble by trying to fit a bad piston seal. Seal should not be tight in cylinder. All you should need to do is present the cylinder to the piston at an angle push over piston and seal then twist square. The shaft bearing is locktited into the casing and onto the shaft. You would need to heat the casing to get it out. I have never seen a 3/32" Allen screw in the crank they are always 1/8". Maybe someone has played with it before. Get the correct seal and DO NOT lubricate it.
 
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