Dear all,
my name is Peter and I´m from Germany.
I´m restoring an old Hadley vacuum driven compressor of the system of my car, which is not a Cadillac, but Cadillac used the pumps in their ALC systems in the '70's.
More or less the O-rings I have found here in Germany in a shop speciallized for such things.
The gasket made out of cork of the front cover I have organized a reproduction. We had the original one digitalized and now a small series of 10 pieces has been produced. I had the choice either to get it in cork or made out of rubber. I decided to have the first ten in rubber.
But now the biggest problem is the diaphragm respectively the membrane of the compressor. This is difficult to have it reproduced because it is not just a plain mebrane.
Due to the fact that I could not find any spare parts here in Germany I started to search in the Internet.
So my concern now is if anyone here knows a source for such parts.
I contacted already Hadley customer service Europe but they said there are no parts available anymore.
Hadley US I´m still waiting for an answer but I must admit I do not hope that they will be able to help.
Maybe there is someone in the US who has started a reproduction.
I´m looking forward to any answer and suggestion from the members of this Forum.
Kind regards
Peter Bauert
Dortmund
Germany
I have a NOS diaphragm for a 67 Eldorado ALC compressor and some nice small used parts. Would they work?
I rebuilt the ALC compressor in my 67 Eldorado. It works but won't stop pumping. After checking for leaks I believe that I have an internal leak. I can't help you Peter but you may be able to help me. Do you know the exact size of the O rings that seal the piston against the cylinder wall?
Cadman, I might be interested in your NOS diaphragm if it is for sale. What other parts do you have?
Thanks
Jeff
I do have a few o-rings and saved the nicest used small parts. I would guess the teflon band sealsand oprings under them may be worn and also the end seals in your system.
Can you put the whole assy. in a bucket of water to check for leaks like is shown in the shop manual and can you put an output pressure gauge in the system?
Cadman56
I haven't done the test as they suggest in the manual but I did check for outside leaks with soap and water and there were none. My brother and I rebuilt the compressor. I think the problem is the check valve and my brother thinks it is the O ring-teflon band seal on the piston. It sounds like you have had some experience with these compressors. What would be your best guess? We are also interested to know what you have for small parts. Please let me know when you get a chance.
Thanks
Jeff
Hi Jeff,
I think is not supposed to stop pumping as long as engine is running.
Peter,
How did you determine that Hadley made these pumps for GM ? How about a picture of your pump? Bob
Here is the video of the pump working.
https://www.youtube.com/watch?v=bPimKjEaOlM
Exactly the way it works in my '72.
Bruce. >:D
Is that correct. The compressor is always running when the engine is running? If this is the case then we have fixed it. I thought that it got to a maximum pressure and stopped. That would be great. One less thing to fix.
Thanks
Jeff
Quote from: 67 Cadillac on December 19, 2019, 12:13:06 AM
Is that correct. The compressor is always running when the engine is running? If this is the case then we have fixed it. I thought that it got to a maximum pressure and stopped. That would be great. One less thing to fix.
Thanks
Jeff
No, the pump gets a constant supply of vacuum, but when the reservoir gets up to pressure (about 280 psi) the pump stalls. That is the point at which the vacuum acting on the diaphragm can no longer move the piston against the pressure in the tank.
That means the pump does not run at low vacuum like when driving at speed or when accelerating. When running properly it only runs when the engine is at idle.
Quote from: Bob Hoffmann CLC#96 on December 18, 2019, 09:23:50 PM
Peter,
How did you determine that Hadley made these pumps for GM ? How about a picture of your pump? Bob
I don’t remember where I found out Hadley made these compressors. Maybe it is marked on them somewhere. At the time Hadley made compressors for air horns, I have one of those. They were sold in the JC Whitney catalog.
Multiple people have contacted them looking for parts to no avail. They claim to not have the ability to reproduce the parts or have dies to cut the diaphragm.
It's a shame that Peter never came back, he is missing out on a lot of good information.
Quote from: Glen on December 19, 2019, 01:07:39 AM
No, the pump gets a constant supply of vacuum, but when the reservoir gets up to pressure (about 280 psi) the pump stalls. That is the point at which the vacuum acting on the diaphragm can no longer move the piston against the pressure in the tank.
That means the pump does not run at low vacuum like when driving at speed or when accelerating. When running properly it only runs when the engine is at idle.
Thanks for info, Glen!
Quote from: Glen on December 19, 2019, 01:07:39 AM
No, the pump gets a constant supply of vacuum, but when the reservoir gets up to pressure (about 280 psi) the pump stalls. That is the point at which the vacuum acting on the diaphragm can no longer move the piston against the pressure in the tank.
That means the pump does not run at low vacuum like when driving at speed or when accelerating. When running properly it only runs when the engine is at idle.
Thanks for that info Glen. I was wondering about that. The one in my 77 Brougham would pump all the time. I left my car on jackstands under the frame overnight and obviously lost any air in the system and my compressor has no output. For now I've disconnected it and replaced the shocks with regular shocks, but someday I may like to get the system working. It must have been working before I got it (or at least someone attempted to) as I found a receipt from Ted Holcombe for a rebuilt height control valve with the paperwork that came with the car.
I don't trust myself with small fiddly bits, but I may have to tackle this one myself as I don't know of anyone who rebuilds them currently.
Thanks for that Glen. How long does it normally take for the compressor to stall (280 psi)? Obviously mine hasn't reached that point yet. I don't remember checking it at higher rpm. I'll have to try that.
The inventor's patent application, owned by Hadley:
https://docs.google.com/viewer?url=patentimages.storage.googleapis.com/pdfs/US2630102.pdf