1974 Fleewood airshocks

[ithaca1230]

Now that we got the old girl running well I would like to get the rear shocks working like they should be. The air system is not hooked up and the shocks that are currently on are not the correct type. I looked up replacement options but cannot find anything on the pump or the leveler switch. Any help would be great.

Thanks agian

Billy

[Scot Minesinger]

Billy,

Understand you want to get the Cadillac correctly working.

If it was my car I would replace the rear springs and shocks with standard deVille springs and shocks - non ALC and then you are good, leaving the air pump in engine bay and saving original parts if anyone ever wants it back to original.  This way you can drive and enjoy the car without issue.  If you travel with six people and all their luggage and a full tank of gas the back may sag a little.  The reality is most enjoy driving their Fleetwoods with few passengers and no luggage much of the time.

Highly recommend you do not go with manual fill air shocks, as you have to fuss around always as they deflate - add compressor (from a remote unit, not car mounted) air, extra passengers get in add air and then passengers get out - let air out.

[James Landi]

I agree with Scott, especially with respect to non-eldorado models (they absolutely need air shocks ).  The first generation vacuum actuated air compressors are subject to failure and hard to rebuild successfully. The electric motorized ones, introduced in the 80's models, are far more durable (and those motorized pumps could be adapted for your car).  Here's some other observations... the original equipment Cadillac air shocks had one shock that had a compressed air input and an output, so that there was no need for a "tee" fitting--- I believe the original equipment "almost original" you'll need to install a tee to service compressed air to both shocks.  My only suggestion (one that Scott disagrees with), is to abandon the air compressor and install a schrader valve in a convenient location so you can inflate the shocks to a rear height that you'd prefer AND also get the benefit of a "stiffer" more controlled rear end and improved drivability .  While he is correct that over time the shocks will slowly deflate, I found that not such a large draw back as the leakage took months, especially on an occasionally used car.  I trust others will have thoughts and opinions and provide other advice.  Happy day,  James

[ithaca1230]

I believe the Compressor is not working. A system from a 80s era vehicle can be retrofitted? This is what I would be interested in doing. If anyone here has successfully done this can you share some details.

Thanks
Billy

[James Landi]

Here are some of the challenges: 

THe 80's air level controller uses an electric height sensor at the rear of the car and that sensor is very different from the one in your car -- it has a sensor that is not electric, but is simply a purge valve that lets compressed air out of the system when the rear of the car exceeds a pre determined height limit  (too high) . When the car is too low, the vacuum pump begins to work hard... if the height is just right, there's sufficient compressed air in the bullet shaped  tank mounted on the pump to maintain the proper air pressure.


ONe the 80's model there is no reserve tank, and the electric height sensor actuates an electric purge valve that is built into the compressor pump.  I'm not certain what would occur if you simply plumbed an electric compressor into the input line where your present vacuum compressor connects. I suspect it would work HOWEVER  I do know that on the "newer" configuration, there is an "inline" safety purge valve where as the safety purge valve on your car is built into the top of the pump --- similar in effect to the one on your hot water tank -- I hope that this post will encourage others to respond as well with more specific advice regarding a retro fit   Happy day,   James

[cadillacmike68]

Here are some of the challenges: 

THe 80's air level controller uses an electric height sensor at the rear of the car and that sensor is very different from the one in your car -- it has a sensor that is not electric, but is simply a purge valve that lets compressed air out of the system when the rear of the car exceeds a pre determined height limit  (too high) . When the car is too low, the vacuum pump begins to work hard... if the height is just right, there's sufficient compressed air in the bullet shaped  tank mounted on the pump to maintain the proper air pressure.


ON the 80's model there is no reserve tank, and the electric height sensor actuates an electric purge valve that is built into the compressor pump.  I'm not certain what would occur if you simply plumbed an electric compressor into the input line where your present vacuum compressor connects. I suspect it would work HOWEVER  I do know that on the "newer" configuration, there is an "inline" safety purge valve where as the safety purge valve on your car is built into the top of the pump --- similar in effect to the one on your hot water tank -- I hope that this post will encourage others to respond as well with more specific advice regarding a retro fit   Happy day,   James

I'd like to do this as will with the 1968. I have manual fill air shocks in it now, but need to inflate them each time we take it out.

I think the electric valve / sensor subsystem from an 80s or 90s RWD system would be needed along with the lines and compressor and electric supply connectors. A place to mount the compressor would need to be identified.

It should not be that difficult but I haven't tied it.

If anyone has any ideas, please post them.

Because there's no way I'm putting that rickety giant pump and tank assembly on the 1968. First, they always fail sooner rather than later and second, you NEED a different Vacuum Manifold - that little grey multi-T-connector up on the firewall. Just Looking at that manifold the wrong way can make it crack, so there's no way I'm even touching that!

Scot may not favor the manual fill shocks, but I do It allows adjustment of the ride height that is impossible otherwise. Most of the time that car only has 1 or two people in it but it always has the heavy toolbox, literature case and amps & subwoofer, so italways needs a little air in the shocks. However sometimes we load it up for a trip with 4 or 5 people, lots of luggage (that when the literature case gets left behind), and on those occasions it needs more air. Even when it needs higher pressure, the air bags in the shocks are so small it only takes a few seconds to fill them.

It only takes two minutes to plug in the compressor, add some air to the shocks and unplug & put away the compressor. I'd prefer not to have to do it when it's only me & the boss lady, but again I get to make a visual check of the tires, etc.

Remember in the Army we were required to do lots of PMCS (which some Soldiers often referred to as PMS checks) EVERY time we took a vehicle out for Any purpose, so a couple minutes adding air and checking oil, is not a waste of time to me.

[James Landi]

Hi Mike and others interested...

I continue to hope that someone has already accomplished a "work around" to replace the old vacuum actuated air shock compressor with the second generation electric pump.   So I feel that since two of you have indicated interest, I had to consider other challenges on a possible "work around."  One of the other engineering features that the 80's electric system had is a three minute shut down if there is a rupture in the compressed air system.   This electronic device ensures that the pump does not keep running for hours on end if the system is calling for air because the car is sitting low, and the pump can't lift the car.    On one of my Eldorado convertibles that Glenn Brown purchased from me, I installed a tee in the compressor line, and ran an inexpensive oil pressure gauge to that tee.  The auto stores sell these pressure gauges for under 20 dollars with an under dash gauge hanger--- this way, I was able to monitor the pressure in the shock system.  I also installed a field relay to the pump, so that, if I wished to further inflate the shocks are raise the rear end a bit more to stiffen the ride, I could do that.  Having the gauge also provided me with confidence that all was well with the system.
I thought about installing an electric pump on my 72 Eldo, but the shrader valve worked well enough, and I only occasionally used the car.   Aside from including the "work around" gauge and in car manual operating button, I think the entire operation, if driven by me, would not be a big challenge to install and maintain.   Clearly, if someone holds down the inflate button too long,you're in for an expensive,loud bang.

[Carl Fielding]

Oh, all right. Billy, before I infuriate the "puristes" around here and yet again desribe the finest solution for you, (you know, replacing the bubble gum shocks with REAL gas shocks, and putting urethane air bags in the coils - you will normally run them at 6-8 psi, they will not leak, and in the extremely rare event that you need to pump them up a little bit more for carrying heavy loads, you can do that with a few strokes with a simple bicycle air pump - make sure to plumb them separately to avoid "cross talk", and bleed when cornering), before I advocate for this perfect solution, before I aggravate my arthritic fingers further, I have a pertinent guestion. Do you want to waste time and money resurrecting the troublesome original flawed system, or would you like to do it right?

I have done this fix on several early to mid '70s Cads, and everyone who has driven them remarks how well this works. (Yes, this DOES work better, and gives an additional benefit : the car will HANDLE better too !). If you feel embarrassed even considering a non-stock solution, standing here in front of the assembled skeptics, you may call me to discuss this further.
                                           -  Cadillac Carl , 206-790-6912,or 408-621-8261

[James Landi]

Lord Fielding!!!!   We do agree that compressed air (and urethane?  --- I thought that was a replacement for varnish on bright work on your royal yacht) does improve the ride in these old Cadillacs --- these systems were featured, as you well know, as automatic level control, but I, having owned a '67 and three 80's Eldorados, always felt that inflating the shocks above the factory specs helped the handling--- as well as help me to see out of the rear window... What day you Me Lord--- your old pal, James

[Glen]

.... the one in your car -- it has a sensor that is not electric, but is simply a purge valve that lets compressed air out of the system when the rear of the car exceeds a pre determined height limit  (too high) . When the car is too low, the vacuum pump begins to work hard... if the height is just right, there's sufficient compressed air in the bullet shaped  tank mounted on the pump to maintain the proper air pressure.

That is an imprecise description.  The level valve at the rear axle works to both inflate and deflate the shocks dependent on the height of the body above the rear axle.  It has a time delay to prevent actuation while going over bumps etc.  It also has a retainer valve to maintain a minimum pressure in the shocks.  The air bags on the shocks can be destroyed quickly in there is no pressure in them to keep them from chafing as the car moves. 
The compressor operates independent of the level valve.  It runs when the manifold vacuum acting on the diaphragm overcomes the pressure in the tank, acting on the piston, about 280 psi.  There is a pressure regulator that lowers the pressure to the level valve to 125 psi, a safe pressure for the shocks 

I have kept the system working on my 68 ELDO since 1973.  It takes a little work but it is possible and worth it.   

[ithaca1230]

Im so confused now on what to do. I am going to look at all the existing components and assess the condition. then will see what parts are not working. The shocks are not air shocks for sure and will look for the switch. I will let you guys know what I find out.

Thanks

Billy