My new (to me) compressor

[MikeAlan]

Hello again,
I could have prioritized blowing the post-bill-paying remainder of my meager income toward something more practical, but probably not something more cool...at least the way I think of cool. I hope you will share my excitement in this, and also that you will be able and willing to advise me on it!
After reading most of the compressor forum posts here, I was messing with the idea of owning a compressor, but was disheartened to learn of the prices of modern machines. I would have eventually been able to afford something, but waiting isn't something I have ever looked forward to, and patience is not a character trait I would know anything about, first-hand. I was killing time and dreaming when I hit upon a listing on Craigslist that looked either "promising", or "too good to be true", depending on my state of mind. Which tends to swing rather wildly. Not to say I am unstable, just...well, my Mom always said I was "special".

us-divers-compressor.jpg

I've got several thousand questions to ask you guys about it. But it'll wait till after some much needed rest, and if there is any interest, I would be happy to describe in detail; how it was, what it is now, and what you guys think I should/could do to make it what it should be.
Briefly: it does pump air, now, though not very fast, and it isn't exactly the same as the US Divers catalog descriptions of the "Alize" compressors.
More soon...thanks.

[antique diver]

Nice "vintage" find.

[Bryan]

Nice!

Sent from my GT-I9500 using Tapatalk

[captain]

Appears to be the French made Luchard Alize sold through US Divers. Shown in the US Divers 1958 catalog.

https://personal.filesanywhere.com/View ... T=Y&Type=F

[Bryan]

That one was not working for me Tom.....Hopefully this is the one you were referencing

https://www.dropbox.com/s/r4fatmk29h95p ... 8.pdf?dl=0

[MikeAlan]

You guys nailed it, though I cannot see any difference from 1958 to 1965 pictures in catalogs. I trust you.
Here's a couple more pics. More to come soon.

USDivers-Luchard2.jpg

MadeInFrance2.jpg

[MikeAlan]

USD_Luchard_Compressor2.jpg

When I got this, it was obvious that it hadn't been run in a long time. Despite the owner insisting that "yes, it works" when I asked him. I really didn't expect an honest answer, and I was still interested anyway, for $300. A little cleanup and fresh paint didn't hurt. I went with colors I thought I saw while looking through the old catalogs available right here on Bryan's site.
This pic is after I took everything apart to check it out, make sure it would run without exploding, and assembling.

The only real stuff to do inside the compressor pump was to re-seat two of the "clappet" valves and replace a busted valve spring on the third stage. Also I had to replace the original fill hose, which leaked everywhere. The local NAPA built me a 4' hose with a rating of 6000 PSI for about $57.00.

By the way, another big "thanks" to Bryan - and to everybody who contributed files to this site. I used the ALIZE MANUAL from the downloads section, while going through the compressor, which wouldn't have been available to me, except for here.

The ALIZE, according to catalogs, came with one filter cartridge, designed to be emptied and refilled by the user using activated carbon, and thick felt pads.
My ALIZE had come to me with two of those filter cartridges. One packed with the activated carbon and the other packed with activated alumina.

There is a pressure relief valve, set to 2400 PSI, as part of the filter cartridge. This doesn't work as intended, as far as I can tell. It blows by all the time, from the moment you fire up the engine. In other words it will not allow the buildup of any pressure beyond maybe 100 psi or so.
After a lot of wondering why, I figured the original spring inside it must be fatigued from many years of sitting around, doing nothing except being compressed a little. I added shims to the spring, several times, adding a bit more shim each time. Didn't seem to help, you could still feel the air dumping out the relief valve. Double checking with soapy water confirmed.

Please don't scold, but in order to see if this thing would actually compress air to a level useful as a scuba compressor, I had to disable/bypass that pressure relief valve. I was careful, wore my leathers and a football helmet, and made sure to bleed out the filter cart every couple minutes. It's the only way I could get it to work, and I quickly shut her down at 2100 PSI.

So I guess my question is how to make the relief valve work with the rest of the system.

[rhwestfall]

Complete brainstorm having never seen the system:

Wondering if some sort of rudimentary "safety" exists where back-pressure on the fill hose (caused when connected to a vessel for filling) would then cause the bypass to close and build pressure?

Fire away....

[MikeAlan]

Complete brainstorm having never seen the system:

Wondering if some sort of rudimentary "safety" exists where back-pressure on the fill hose (caused when connected to a vessel for filling) would then cause the bypass to close and build pressure?

Fire away....

Thanks for your input.
I don't think that's the case, but I cannot put into words why. I had the compressor connected to a cylinder to verify it would build pressure.
I'll take some pics of the relief valve, and try to post them with a description, and why I cannot see how it ever worked. Obviously it DID originally work, so I'm at a loss either way.

[antique diver]

Aaach!... Fire One! (Cool compressor, by the way, but concerned about your safety... so I look forward to helping in any way I can)

Is that a hardware store variety pipe cap in place of your final relief valve? Looks suspiciously like a cast iron 125 psi fitting.

About the relief valve - the seat material is probably worn or corroded and failing to make a good seal. Could be metal to metal, or metal to a softer material, but neither lasts forever in that kind of service. If you can get me a few good photos of interior relief valve parts maybe I can offer some suggestions.... but best bet may be to replace the relief valve, as it is VERY important to your continuing to dive with all your body parts intact.

That will require some careful matching of the threads on your existing relief valve, and I'm not sure what may have been used in France in that era.
A good photo of the valve body threads if they are male, plus show any washers or similar sealing materials will be helpful. Check to see if the threads appear to be tapered like our common pipe threads. If at all possible use a thread pitch gauge to accurately measure the threads per inch or per cm. Also, a caliper accurate reading on the outer diameter of the male threads at both ends of the threaded area.

Nice piece of diving history you have!

[MikeAlan]

Aaach!... Fire One! (Cool compressor, by the way, but concerned about your safety... so I look forward to helping in any way I can)

Is that a hardware store variety pipe cap in place of your final relief valve? Looks suspiciously like a cast iron 125 psi fitting.

About the relief valve - the seat material is probably worn or corroded and failing to make a good seal. Could be metal to metal, or metal to a softer material, but neither lasts forever in that kind of service. If you can get me a few good photos of interior relief valve parts maybe I can offer some suggestions.... but best bet may be to replace the relief valve, as it is VERY important to your continuing to dive with all your body parts intact.

That will require some careful matching of the threads on your existing relief valve, and I'm not sure what may have been used in France in that era.
A good photo of the valve body threads if they are male, plus show any washers or similar sealing materials will be helpful. Check to see if the threads appear to be tapered like our common pipe threads. If at all possible use a thread pitch gauge to accurately measure the threads per inch or per cm. Also, a caliper accurate reading on the outer diameter of the male threads at both ends of the threaded area.

Nice piece of diving history you have!

Thanks, It could be a hardware store cap for all I know; it was on it when I got the thing. But, I wasn't aware of the 125 PSI rating on it, so thanks for that tip...
When I first fired her up, she leaked at EVERY connection, which I repaired one by one. But just in order to make it compress air at all, I took off the second filter cart, thinking that the more original to factory equipped should be better, and then after much trial and error, eventually used the filter cart that had that 125 PSI cap on it in order to eliminate the relief valve from the equation.
I'll get some pics together as soon as possible for you, and thanks again.

[antique diver]

I was guessing from the photo, but the cap could be of HP quality. A close up of that may help us determine its suitability... Just want you to be safe.

[MikeAlan]

I was guessing from the photo, but the cap could be of HP quality. A close up of that may help us determine its suitability... Just want you to be safe.

That's very kind of you, thanks.
I'm gonna go snap some pics and get back here later tonight.

[MikeAlan]

I was guessing from the photo, but the cap could be of HP quality. A close up of that may help us determine its suitability... Just want you to be safe.

cap-one-quarter-pipe.jpg

Here's just the cap, and it's not a great picture, so if a different angle is needed please let me know.
I am working on the pics for the relief valve, which should be ready soon.
THANKS everybody!

Not to say I know, but I think it must be a higher rated cap because it held up fine at 2100 PSI...a few times.

[antique diver]

It's hard to tell for sure but it looks like a regular galvanized pipe cap. I don't want to be an alarmist, but I also have concerns about the possibility of a thread mismatch between the French parts and the cap, or maybe in the lower fitting. I see stuff like that happen from time to time, but thankfully accidents are rare.

I have a fair amount of time in the HP air and gas business, but it's difficult for me to determine the facts you need to know from here. I will continue to try to help, but also encourage you to seek out a local source with a good knowledge of thread and material types... not always easy to find. I just noticed you are in San Diego, which should have some good sources.

Please continue with photos and measurements and we will probably make some progress.