Page 2 of 2

Re: BAGS VS SPRINGS

PostPosted: Wed Feb 17, 2010 8:17 pm
by oldschool1
Dereck wrote:Hi Guys

Sorry to say it but the Mark vii's air ride system sucks royal goats ass for comfort compared to Citroen's hydropneumatic suspension :P

Regards

Dereck

<OS scratches head ... goes to WikiPedia>

Reposted from http://en.wikipedia.org/wiki/Hydropneumatic_suspension

Hydropneumatic is a type of automotive suspension system, invented by Citroën, and fitted to Citroën cars, as well as being adapted by other car manufacturers, notably Rolls-Royce, Mercedes-Benz and Peugeot. It was also used on Berliet trucks. Similar systems are also used on some military vehicles.

The purpose of this system is to provide a soft, comfortable, yet well-controlled ride quality. Its nitrogen springing medium is approximately six times more flexible than conventional steel, so self-leveling is incorporated to allow the vehicle to cope with the extraordinary suppleness provided. France was noted for poor road quality in the post-war years, so the only way to maintain relatively high speed in a vehicle was if it could easily absorb road irregularities.

While the system has inherent advantages over steel springs, generally recognized in the auto industry, it also has an element of complexity, so automakers like Mercedes-Benz, British Leyland (Hydrolastic, Hydragas), and Lincoln (Air suspension) have sought to create simpler variants.

This system uses a belt or camshaft driven pump from the engine to pressurise a special hydraulic fluid, which then powers the brakes, suspension and power steering. It can also power any number of features such as the clutch, turning headlamps and even power windows. The suspension system usually features driver-variable ride height, to provide extra clearance in rough terrain.

The suspension setup is referred to as 'oléopneumatique' in early literature, pointing to oil and air as its main components.

There have been many improvements to this system over the years, including variable ride firmness (Hydractive) and active control of body roll (Citroën Activa). The latest incarnation features a simplified single pump-accumulator sphere combination.

The system had one key negative impact on the inventor, Citroën - only specialist garages were qualified to work on the cars - making them seem radically different from ordinary cars with common mechanicals.

Auto manufacturers are still trying to catch up with the combination of features offered by this 1955 suspension system, typically by adding layers of complexity to an ordinary steel spring mechanical system.

***************************************************************************************************************************
At least Lincoln was mentioned :)

John "I-Like-My-AIR-Springs" Dancy

Re: BAGS VS SPRINGS

PostPosted: Thu Mar 11, 2010 5:01 pm
by hansa
Image
Pic from StangMark topic: Bar and Grill , Junk Yard Journey
Heh :lol: Look the spring. After marked and now cut
EDIT
Hmm. I looked better the pic. Home made. Some welded points :lol:

Re: BAGS VS SPRINGS

PostPosted: Fri Jan 28, 2011 10:59 am
by oldschool1
Bump.

I have a set of rear air springs that have lived a long and productive life. They now leak.

If the weather ever changes to ABOVE freezing in Pennsylvania, I'll replace them with ... air springs.

Re: BAGS VS SPRINGS

PostPosted: Tue Oct 18, 2011 9:00 pm
by maviirk
i noticed this post a little too late, but maybe i can revive the subject, even just to share my opinion....i converted my car to the coils from strutmasters, and i regret it everyday, we had to create a way to hold the front springs in place on the lower side, and they are massively stiff springs, going over easy highways imperfections isn't so bad, but otherwise, potholes and bumps are brutal, and the suspension constantly creaks and squeaks, my bad for not researching it better, the car neads new heads now, but if i plan on keeping it, i must say, air bags are going back in it, these cars were designed with this air suspension system in them, thats the way they are intended to be, in my opinion. i will admit it is a little more stable feeling under hard cornering, everything else about it sucks. glad i kept the compressor and lines in it.

Re: BAGS VS SPRINGS

PostPosted: Tue Oct 18, 2011 11:45 pm
by oldschool1
Thanks for the review.

Re: BAGS VS SPRINGS

PostPosted: Fri Jun 15, 2012 11:10 am
by oldschool1
Bump.

Re: BAGS VS SPRINGS

PostPosted: Fri Jun 15, 2012 1:45 pm
by White Lincoln
I was impressed with gadgets comment over on LOL about Mark VII suspensions systems and thought I would mention it here:

"And thats where the issues tend to start. Believe it or not, its usually cheaper and easier to repair the stock system than it is to convert it to parts that were never intended to be there."

Here is the whole comment so it all makes sense:

"Quote:
Originally Posted by Redwood
I could buy one of those kits and get rid of the air suspension forever, right? That seems like the way to go if I would start having issues with it. [end quote]

"And thats where the issues tend to start. Believe it or not, its usually cheaper and easier to repair the stock system than it is to convert it to parts that were never intended to be there. The air suspension is stupidly simple to work on once you learn how its supposed to work. The parts are not that expensive, in fact you can buy all 4 air springs for less than a conversion kit most of the time. They are also a piece of cake to swap out. The thing is, most shops don't understand the system and don't want to. Thats where a knowledgeable owner with a handful of common tools can save themselves a huge amount of money. I'm a big fan of the air suspension system, but I acknowlege that its the subject of much fear and misinformation. Ditto the ABS. That truly is a black hole of nonsense, but usually it can be worked out without huge amounts of bother if you know how to diagnose it. Its completely unlike most other brake systems though, so a lot of times people look at it and go OMGWTF! A shop manual is simply indespensable on one of these cars, as is either some owner involvement, or a guy that understands Lincolns and their systems."

you're still my hero gadget...

Re: BAGS VS SPRINGS

PostPosted: Sat Jun 23, 2012 2:45 pm
by mikeceli
MANY of today's Mechanics were in there PLAYPENS, when our Lincoln were built!

Air Suspension and Teeves ABS must be worked on by Mechanics who understand thee system or are willing to study the FSM.

(Study on who's time)?

Re: BAGS VS SPRINGS

PostPosted: Wed Jul 10, 2013 4:41 am
by oldschool1
Image

Bump.

Re: BAGS VS SPRINGS

PostPosted: Wed Jul 10, 2013 8:10 pm
by tomnh
Air Springs give you a better ride then the coils. Also they are easier to work on and fix.

I can change the airsprings on my car on the side of the road with just a few hand tools. Don't ask. I have done one front and one rear on the side of an interstate and it took less then 1/2 hr for each.

I replaced the pump and dryer a couple of years ago. that took me an hour (stupid plastic air lines).
I have replaced coils back in the day and they were all a pita. Torsion bars are neat, but also a pita to work on. :twisted:

Re: BAGS VS SPRINGS

PostPosted: Sat Oct 26, 2013 6:13 pm
by oldschool1
Two of my cars have front air springs that have lived a long and productive life. They now leak.

When the weather changes to ABOVE 60 degrees in Pennsylvania or we finish up with the current project in the shop, I'll replace them with ... air springs.

Re: BAGS VS SPRINGS

PostPosted: Sat Oct 26, 2013 6:40 pm
by mikeceli
IMO, eliminating ABS is the first stop on the road to Lincoln Mark VII "Parts car" status. Metal springs are the second stop.

Re: BAGS VS SPRINGS

PostPosted: Sun Jan 26, 2014 10:00 pm
by SUPERWIDESEC
they use the same design on rollsroyce silver shadow and silver spirit / silver spur . i hate them ! when ever you need to change anything on them it's crazy money. and for those who say "i you have to ask maybe you can't afford it " ? anyone who don't is crazy . well i own two 2002 and 2009 and a bentley ( just a rebadged heavy springed rolls ) and so far i owed 14 . all of them drove and road like a 1988 pick up truck. i building a hot rod out a 1997 bentley rt and i'm changeing over to ifs in front and 4 link ford in the rear , all coil over springs . the outsides/inside are like art work . thats why i buy them . i don't want anything connected to the motor but a trans .

Re: BAGS VS SPRINGS

PostPosted: Tue Jan 28, 2014 7:48 am
by floodking88
i just recently replaced "barely" leaking 24 year old original BB springs with... air springs. i'd never replace what makes my car better then my friend's skull crushing 5.0 mustang.

Re: BAGS VS SPRINGS

PostPosted: Sun May 11, 2014 1:13 pm
by oldschool1
bump (due to warm weather)

Re: BAGS VS SPRINGS

PostPosted: Fri Sep 29, 2017 4:25 pm
by oldschool1
Bump
... for 2017 :)

Re: BAGS VS SPRINGS

PostPosted: Sun Nov 26, 2017 9:25 pm
by Brad4d
When I first started looking at VII's a few years ago(yes, it took that long to find the one I wanted) I'd usually see them for sale saying something like, "converted to coil springs, from the problematic air bag system". Seemed to make sense, but now I see that isn't entirely true. It's more like "converted, because the mechanic at the local garage didn't know what the heck he was looking at, & found a cheap conversion listed". At some point I'll look further into what has survived from the original system on mine, but it does have coils now. Drives real nice, which, because I've grown to trust info on this site, leads me to believe air-bags must be amazing. I read about deformation at mounting points, from the steel springs(and others saying it doesn't happen), then noticed the LSC I've had for a few weeks is sitting about one inch lower on one side, in the rear. PANIC mode...$$$??? Turns out from a quick look, its actually one inch higher, it isn't sagging at all. On one side, a spring has shifted sideways, and a body seam is resting on the second coil down! There are no perches on either side, to locate the springs.....hackers!! Not a difficult fix, but stupid to have left them that way, when changed over. Once I figure out the size of spring in there, any suggestions on a decent coil spring perch, an source? I don't need adjustable perches or anything. Just something that works. I might try an auto salvage, once I know what I'm looking for. Eventually I'll look into what is left of the original system, and what going back to bags will cost.

Re: BAGS VS SPRINGS

PostPosted: Wed Nov 29, 2017 12:11 am
by oldschool1
Brad4d wrote:... Seemed to make sense, but now I see that isn't entirely true. It's more like "converted, because the mechanic at the local garage didn't know what the heck he was looking at, & found a cheap conversion listed".

Welcome home.
Brad4d wrote:At some point I'll look further into what has survived from the original system on mine, but it does have coils now. Drives real nice, which, because I've grown to trust info on this site, leads me to believe air-bags must be amazing. I read about deformation at mounting points, from the steel springs(and others saying it doesn't happen), then noticed the LSC I've had for a few weeks is sitting about one inch lower on one side, in the rear. PANIC mode...$$$??? Turns out from a quick look, its actually one inch higher, it isn't sagging at all. On one side, a spring has shifted sideways, and a body seam is resting on the second coil down! There are no perches on either side, to locate the springs.....hackers!! Not a difficult fix, but stupid to have left them that way, when changed over. Once I figure out the size of spring in there, any suggestions on a decent coil spring perch, an source? I don't need adjustable perches or anything. Just something that works. I might try an auto salvage, once I know what I'm looking for. Eventually I'll look into what is left of the original system, and what going back to bags will cost.

My favorite source for suspension parts, https://www.arnottindustries.com/, did not list perches individually at their site.
I'm at a loss.

Re: BAGS VS SPRINGS

PostPosted: Wed Nov 29, 2017 8:02 pm
by Brad4d
Thanks for that link John. My nephew has a company modifying Jeeps & 4x4 suspensions. I'm thinking he'll know where I can source something. The rubber stops are still there, so I'll have to measure the spring diameter, and see if I can mount it from the stoppers bolt. Or remove stopper, & add holes to mount it. If he doesn't have a source for a part, he can probably make one. From what I've seen, they aren't exactly cheap. Hopefully a closer look in the spring will show a lot of the air system in place, & I can put it back to the way it was designed to function. Maybe even adjustable, for a bit of the lowered look for the cruise in...LOL Psshhtt psshhtt Low ride er....gonna' ride a lill' lower... :lol:

Re: BAGS VS SPRINGS

PostPosted: Fri Dec 01, 2017 3:31 am
by oldschool1
You are welcome.