Vacuum powered Air Ride Compressor

[Aprules2]

Hey everyone, the air ride compressor on my 75 Coupe DeVille finally gave up today. I could only find a junkyard that puts good pieces together and then sells you one for $300 so I said if they can do it so can I. I searched the net and I couldn't seem to find anyone who has taken one apart before or a tutorial on how to get them going again. But I happened to have one from an older Caddy sitting around in the garage, it looks the same just the tank was about double the size. I figured Id take it apart to see how it works before I accidentally destroyed the one I needed in my 75. Well after taking it apart I was shocked at how simple it is. Considering I couldn't find any info I thought it would look like it was NASA Engineered. After about 30 mins I had the older one revived, and it now works fantastic. I plan on doing mine for the 75 tomorrow or Wednesday. Would you guys like me to put some pictures up of how to get it going or is there no real interest?

[The Tassie Devil(le)]

Welcome to the world of self-fixing.

I did the same with my own, but had to have the internal of the reservoir sand blasted as it was very rusty.

Bruce.

[76eldo]

Please post a step by step guide if possible. I'd be very interested.

Brian

[chrisntam]

Please post a step by step guide if possible. I'd be very interested.

Brian

+1

yes, please do!!

[Aprules2]

Ok no problem guys. Ill take a few pictures for you its surprisingly simple to work on. I wish I knew a company that I could use to re-manufacture the diaphragms, and rubber stops for us then we could do a real rebuild.

[Glen]

Be sure to clean the regulator. 

Instructions at http://www.planeteldorado.com/ALC/

["Cadillac Kid" Greg Surfas 15364]

Aprules2,
Your post reminded me that I bought 2 Diaphram kits when I needed to rebuild my Eldo pump and still have one.  Its a NOS  Delco PN 3188818 Diaphram repair kit including the diaphram and the O-rings needed to replace it.  I also found a NOS Second stage housing.  I believe I also have a NOS regulator.
PM me if you are interested.
Greg Surfas

[TJ Hopland]

NOS parts may be handy for someone to have that is looking to get some new parts manufactured.   

[Aprules2]

That would be great, honestly the components look similar to the ones in the fuel/vacuum pump on my 55 Buick. Any company that makes those kits should have no problem making them for us, the hard part is motivating them. I had dealer optioned Cars & Concepts T Tops on my 80 Trans Am and people were paying outlandish amounts of money for NOS weather stripping, or having their roofs cut off and welded to switch to different T-Tops or a hard top because they couldn't find replacements. I almost went the same route, then I got lucky and tracked down a set and bought them. I tried calling Soffseal to have them duplicate them so they could carry them, or at least let me pay for a large run of them and they weren't interested. So I don't really know how to go about it.

[TJ Hopland]

With all the new manufacturing and design processes (and global locations) out there today you would think it would be easier to get things made even on small quantities.   You then add the internet for an inexpensive way to find buyers you would think there would be a chance for at least a slight profit. 

An air ride compressor is one thing and something that has several options for workarounds if you can't get parts but the example of cutting and welding the whole roof of your car because you can't get a gasket seems crazy.  It would seem if that was your only option to keep a car like that from leaking that you could charge $100's, if not $1000's for a new gasket.   Sure they are not likely a lot of 80 T tops on the road but with that kind of a possible profit margin you would think someone would try it.   

[Aprules2]

Unfortunately TJ bankers make these decisions, I wish "Car Guys" were making parts for car guys. There would be a lot more cars on the road, instead of the cookie cutter cars you always see at car shows. These companies literally decide what cars can be restored, the average joe cant afford to have sheet metal patches custom made, moldings and emblems cast, or 5000 at an upolstery shop to get a new interior. But if you have a Chevelle or 65 Mustang you can restore it through a catalog for a 3rd of the price its such a shame....... My first car was a 74 Olds 88 Convertible and I still have it unfortunately it will probably never get restored because of these practices...

But enough of my rant, heres an update on the compressor rebuild. I took the 75 one apart and got it all freed up and running, the bad part is the diaphragm has to slit shaped holes in it. Explains why I never got more than 30lbs of pressure out of it. So I only have pictures of the tear down and to lubricate the top part of the pump. Im debating on just taking the Diaphragm out of the older pump and putting it in my housing they appear to be exactly the same. I jut hate to ruin another classic caddy part. It looks to be older and I was thinking of selling it to a member who could use it. I was told it might be from a late 50s early 60s caddy by my friend who gave it to me........

[Aprules2]

OK First here's the older one I have, its huge compared to the 75 if anyone knows what its from let me know





Here is my 75 Compressor, I removed it from the car with the brackets attached it seemed easier that way..


So the next step is to remove the (2) 3/8 nuts holding the bracket to the rubber mounting bushings... If yours is like mine the bushings will be practically glued to the bracket. I took a thin screwdriver ad worked my way in between and was able to separate them. Be careful they probably aren't available new.



When I tear something like this apart I like to do it in a box of some sort so things don't get lost and take lot of pictures so I don't put bolts back in the wrong place.. You can see here I removed the 2 bushings


Remember this bolt its different from the others


The way the front pump is built 3 bolts hold the two halves of the pump housing together and then the ends of them protrude through the tank and help secure it to the tank. The rest of the bolts just hold the pump to the tank. So what I do is remove the 3/8 nuts from the back (on the tank side) some bolts will spin as you attempt to remove the nuts these are the through bolts holding the pump to the tank So remove them all, then JUST REMOVE THE NUTS from the other ones.



Now while I still have the tank attached to use as a stand I remove the cover on the top pumping mechanism. There should only one bolt securing it by this point.

http://i492.photobucket.com/albums/rr290/aprules2/75%20Caddy/Air%20Ride%20Compressor/IMG_20140403_171557_137_zps7adac2b1.jpg

The cover stuck on mine. I don't have any parts, so I cant risk ruining the cork gasket underneath so I tapped all around it with a rubber mallet until It came off. Then any where it was stuck I carefully peeled off the cover so I didn't rip it. Here is the mechanism with out the cover... The only moving parts are the rod, cam, and that plate the spring sits on.



Unfortunately this pic didn't come out too great... But what I do is clean all the crap out of here. I don't recommend taking the cam apart there seems to be a lot of little parts inthere and odds are they will be a pain to get back in place.... I took the flat head screw out of the plastic part the spring sits on. I couldn't get the plastic rings the spring attaches to off and was afraid to break them. So I tilted the rod to the side and moved the cam and was able to sneak the plate out in this pic..... Once you have it out wipe all the old grease off with a rag that you sprayed with wd 40 or break clean. I prefer brakecleen, because it leaves no residue, then get something small like a tiny screw driver or a shiskabob skewer and rap the towel around and clean on both sides of the cam. To get all the old grease and crap off...



Now using that shishkabob skewer or what ever, get into all those tight areas and apply a light layer of grease to everything. Then smear a little on the spring and to rods the plastic piece for the spring rides on. Basically we want everything to have a light layer of lubrication so it can slide freely. In the pic below I hadn't cleaned the same or lubed it yet I'm sorry....


There appears to be a pic missing somewhere from here... But At this point I removed the 2 8mm bolts from the control valve, tapped it twice with the mallet and wiggled it out, then I went from behind the pump assembly and tapped the pump housing with the mallet and it fell off the tank. This is when I got my first let down. Apparently a new pump never connected sitting in a damp garage for 40 years looks like crap inside....




When I have something like the tank that would take forever to clean out by hand, and I currently don't have a working sandblaster I use Oxalic Acid. So I took a 1/4 Teaspoon of powder and poured it into an empty water bottle and then filled it with hot water. Capped and shook it. Then propped up the tank so it wouldn't spill and poured it in, I did that 3 times so it was full and left it over night. Heres the stuff I use....



Now take all the bolts out of the pump and catch the little nuts that come out the back you may want to take a pic to see where all the bolts go so you can put them back in the right spot.... Once you do that the 2 halves of the pump body will fall apart. If they stick just tap them a little, or CAREFULLY tap flat head crew driver into various parts of the seam until it pops. Just be careful not to tear the diaphragm. Once you pop it apart you ll be looking at these 2 halves...




Now this is when I noticed my diaphragm had blown out... So I kind of prepped things to pick up when I decide what I am doing....




As for the back of the pump I scrubbed it the best I can with a brass brush, then cleaned it with brake clean and layed 2 coats of clear on it. It came out pretty good.

[TJ Hopland]

It looks a lot like the stuff that is used in things like fuel pumps and the fuel / vacuum pumps.   

Has anyone asked the fuel pump re builder people if the people that make their materials could make parts for these?

[Aprules2]

Ive talked to a few guys they seem like they maybe interested in making me one at least if not maybe making a rebuild kit. Im trying to get them motivated to do it for us so we can have more Caddies running proper Automatic Level Control. Going from a 75 with out ALC to a 75 with ALC you see how much softer and smoother the car can really ride. Ive never been in a car that rides this smooth before...