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The only place for a coil spring is up Zebedee's arse.
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Joined: Aug 10 2019
Posts: 18

Hello all, haven't posted in a while. I've been driving the Rangie all winter and so far this summer. I've parked it for various minor catch up repairs and driving the Disco instead.
I have the front and rear screen washer pumps and such sorted as well as the cruse control. Working on Hella driving lamps and EAS components now.

This brings me to the question. In checking components to prepare for the swap back to air springs and running through things with Nanocom the compressor didn't run. The error is "Thermal Switch Over Temp". I pulled the compressor and took the motor apart. Found a fair amount of carbon but the brushes still look good. I've cleaned everything up with electronics cleaner, cleaned the commutator slots and gave it a gentle polish. The thermal switch is reading closed with an ohm meter. I don't much like the readings on the pole plates, but I was going to put it back together and give it a try when I noticed a ring in between the PC board and end bell of the motor. It's just loose and moving all over the place.

The O.D. of this ring is stepped. The inner step fits into the hole in the PC board perfectly and the outer step won't let it pass through. It seems that is where it belongs but I don't see what is supposed to hold it there.
Any ideas?

While on the subject of EAS parts does anyone have any experience with a company out of Germany called "AEROSUS"? Prices look good to me.

Thanks for looking

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Joined: Dec 03 2019
Posts: 33

Hi, on the compressor front I don't think I'll be much help, except to say that once overheated (and it sounds probable) the other end of the compressor will almost certainly need overhauling, something I haven't had a great deal of luck with as it goes, I recently bought a new Dunlop compressor from ebay for £160 and I reckoned that was cheap enough not to bother.

As for springs plenty of suppliers in the UK supply them (Dunlop OEM) for about £60 or £65, mine came from Paddocks about 4years ago. and hopefully I'll get another couple of years out of them. The only alternative manufacturer that seems to be popular (but much more expensive) would be Arnotts, but you are buying an upgrade. The Aerosus seems equivilent or even the same as the Dunlop for slighty more cash and a longer delivery (assuming you are UK based?) [edit, just noticed you are across the pond, probably comes down to carriage prices and import differences]

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Joined: Dec 30 2015
Posts: 1963

An upgrade/downgrade depending on the luck of the draw, but at least their warranty will cover you in the USA.

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Joined: Dec 30 2015
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The ring at the back is there to hold the brushes back when you fit the rear cover. You pull it up so it holds the brushes, then as you put the back plate on the commutator the ring is pushed in to release the brushes. The thermal cutout is also on the PCB on the back of the motor. If the motor gets too hot it goes open circuit and as it cools down goes short circuit again. However, after they have switched a few times, they fail and stay open circuit. It is connected between the Black and Orange wires on the motor so easy enough to check with a meter. If you have continuity between the two wires, it is OK, if open circuit that would mean it is either too hot or the switch has failed. In the case of an open circuit, the EAS ECU will not try and power the motor as it thinks it has overheated. They can be replaced but are a real pain as it involves drilling out the rivets that hold the PCB in the back of the motor.

The Aerosus springs appear identical to OE Dunlops from the pictures and, as you are outside the EU so won't have to pay the 20% VAT, OE Dunlops from Island 4x4 will be cheaper. At least you know what you are getting with Dunlop. There used to be some Chinese made Dunlop copies around which only had one O ring rather than two so would always leak. The Aerosus ones may be these but you don't know. With Dunlops you know what you are getting.

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Joined: Sep 14 2016
Posts: 477

I don't think Blanco needs to be overly worried about the life of his air-spings yet. My Dunlops are approaching 10 years old and got their first advisory about minor perishing on the MoT last week. My inspection suggests they ought to be good for another year at least.

General consensus seems to be 60,000 to 70,000 miles or 10 - 12 years are reasonable expectations. Mine will age out rather than mileage out, maybe hit 25,000 miles at most. Seems logical that air-springs should age out at a similar rate to tyres so going much past 10 years will be pushing the envelope.

My 65 th birthday "me to me" present Yamaha GTS arrived on 2005 dated tyres with interesting (?!) effects on handling. The now sorted R75/7 BMW clogging up my bike lift wears either 1984 or 1994 dated tyres. Anyone who thinks I'm road testing that needs to stop taking the high test optimism pills.

Clive

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Joined: Aug 10 2019
Posts: 18

Thanks for the replies guys.
I have a full set of Arnott Gen. II's if I recall on the other P38 that has been sitting on the bump stops for almost 12 years now. I was thinking of just doing a swap over between the coils and air springs between the two vehicles but I remember not being all that overwhelmed with the ride after installing them. But I also replaced the shocks and tires (yes I'm across the pond) at the same time and those were probably the more likely suspects for the ride quality.

You know it never occurred to me that the ring may work to hold the brushes back. I'll give that a shot. I was more concerned about having a piece of metal flopping around in the back of the motor possibly shorting out the commutator.
I did check the thermal both across its pins and at the plug end of the wires and it is definitely a closed circuit as it should be. The compressor turns freely but I'm still a little suspicious of the pole to pole readings I'm getting on the bench so It may not be turning electrically and acting as a toaster instead.

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Joined: Dec 30 2015
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Gen 11s have a reputation for coming apart and dropping you to the bumpstops at the least convenient moment, and they are a lot more expensive than Dunlops and don't really give you anything extra other than unreliability. The floppy ring is plastic so won't short anything out.

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Joined: Aug 19 2019
Posts: 184

I don't know about the Gen 11's, I had Gen 111's. I loved the way they rode, both on and off road. They are a bit stiffer than Dunlops in normal and highway modes, giving less body roll, and then soften in lift mode. Also, if you want more lift, they can give you an extra 2". I had the issue that Richard mentioned, so I went back to Dunlops. If anyone is interested in the Gen 111's, I would be happy to part with them for a good price, less than 2 years on them.

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Joined: Aug 10 2019
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Huh, and all this time I thought Arnotts were the coolest thing since sliced bread. Just goes to show ya'.
I'll probably end up with Dunlops but the ones from Germany kind of intrigued me.

The ring for holding the motor brushes worked a charm. Thanks, Richard. I didn't realize it was plastic. It has the color of metal but there's no room to fiddle with it enough to really know unless you take the PC board out or break one. Any way pump runs fine with two wires direct to the battery, fused of course just in case. Blows air but don't know if it's enough or not. Also, I haven't plugged it back into the harness yet to see how the thermal works.

I'll have to pick up more fittings and rig up a pressure gauge and quick fill for the tank as well as end caps for the lines then check the valve block. In the meantime still working with driving light wiring and going to get started on blend motors next.

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Joined: Dec 30 2015
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It isn't whether the compressor blows enough air or not but does it generate enough pressure. It should output around 150 psi so if you can put your finger over the output and keep it there, it isn't giving enough.

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Joined: Aug 19 2019
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I thought the Arnott's were the coolest thing too. They do work as advertised. They stand behind their warranty. But I had 2 fail in less than 2 years. Fortunately I wasn't far from home either time.

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Joined: Dec 30 2015
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Arnotts are only considered cool in the US where anything with Made in USA on it is regarded as vastly superior to anything made anywhere else even when it isn't. I've imported about 30, mostly European built, cars from the US over the last 10 years and spent many hours removing 'upgrades' to make thing work properly.

The Gen 111s give extra suspension travel if you really need it (and most people don't) but the Gen11s are best known for falling apart. A lifetime warranty is all very well but not if you have to fall back on it regularly, you want something that just works as it should all the time.

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Joined: Dec 30 2015
Posts: 1963

It's a two-year warranty.
I'd buy Arnott III if they were proven reliable. I like the theory of being stiffer when shorter and the extra travel would be fun (although nowhere near essential as I don't think I've ever reached the limit of the Dunlops).
However, the Dunlops are a very persuasive price!

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Joined: Aug 10 2019
Posts: 18

Just to clear things up. I do have experience repairing and maintaining manufacturing and industrial equipment in many plants in Texas, Washington State and Kansas. I was a primarily and controls and instruments electrician but very often was deeply involved in the mechanical aspect as well.
Most recently I retired from Spirit Aerosystems as an electrician in the fuselage department where they build up and assemble all variants of the 737 fuselage into complete airframes and I worked daily with 9 and 12 axes automated riveting gantries and C-Frame machines that drilled and filled +/- .003 across the length of a 25-foot window panel.
Some of these machines were Brotje from Germany some were GEMCOR from the US. I've worked on Swedish, Italian and probably a few places I don't even know about over the past 37 years.

So just, so we understand, "blowing air" is just a turn of phrase. I know it takes pressure and volume to make pneumatic devices work properly and when I get the connectors, tubing and gauges together and installed I will have that info.
I'm also not dead set on "Made In The USA". I do like to support the US when it makes sense but other countries often times make superior products. I like German engineering and detail. I but Russian or British vacuum tubes for my vintage stereo gear. I feel they are better products.

Just needed to say that this morning for some reason. I'm feeling much better now thank you.
And by the way....I think my foster Greyhound may be going to a happy home this evening.

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Joined: Dec 30 2015
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Didn't mean to cause offence. A compressor that has a completely worn seal will still appear to be pumping air and it isn't unknown for people to put their hand next to the output and if there is anything coming out think it is fine. It's only when you find you can put your finger over the end and keep it there that you realise it may be doing something but nothing like enough. I went to look at one car where the owner said he'd checked the pump and it was fine, yet when I checked it, although it seemed to be working, there was so little pressure being generated there was no way it was going to lift the car off the bumpstops.

I don't have a problem with people fitting upgraded components when they really are an upgrade (the Direnza alloy radiators being a good example) but what annoys me is when people fit something that is both more expensive and not as good as the original purely down to marketing or perceived superiority. We've got a box of MSD distributors and ignition amplifiers that have been taken off imported cars and replaced with OE Lucas units that work far better as they were designed for the car and not a generic unit with an advance curve that may or may not be something close to what the engine requires. In fact, one particular MSD product, sold for around $100, specifically intended for use on a Porsche and claiming to give a better spark and more power, turned out to be an empty die cast box with a weight inside it. That and the stories of Arnott springs coming apart while a car is parked doesn't fill me with confidence at all.

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Joined: Aug 10 2019
Posts: 18

No offense taken really Richard. We have history. Just felt I needed to explain my point in detail for some reason.
What I should have probably said was "Hey, it runs, and it is even pushing air out the hole. I don't know if it's enough yet or not but I'll find that out when I need to."

The Direnza radiator is doing great by the way. And I haven't forgotten your help in getting it to me. It does look a little odd and even somehow disappointing maybe that it doesn't look more like an OEM but the performance is well worth it. We've already seen from 14° F to 104° F and the temp gauge has been steady as a rock.
Good to know my thermostat is working too.