Air Couplings with CO2- Why are they leaking?

shortyjacobs · 10-31-2009, 11:29 PM

Hi folks. I bought this and this:
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=34705
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93104

Both are Central Pneumatics. I'm trying to use them as a CO2 Manifold.

When i plug the "male" part into the "female" part, it leaks CO2 like crazy....not a slight leak, but a big massive huge leak. I tried hitting it with 40 psi, and 10 psi....it won't seal. Only way I can make it seal is to pull on the collar on the female part, (to retract the ball bearings), and push the male part until it bottoms out and stops leaking...

Am I missing something here? Should there be o-rings on the male parts? I figured since they are the same manufacturer, they should work.

middleofnowhere · 10-31-2009, 11:45 PM

There are different styles of the male part....maybe those just don't work together.

JKoravos · 11-01-2009, 12:09 AM

They could just be crappy, I guess.

Also, compressed air is typically used around 100psi, maybe they only seal at higher pressures.

marzsit · 11-01-2009, 12:27 AM

Quote:

Originally Posted by shortyjacobs

Hi folks. I bought this and this:
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=34705
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93104

Both are Central Pneumatics. I'm trying to use them as a CO2 Manifold.

I figured since they are the same manufacturer, they should work.

they are the same brand, but probably not the same manufacturer... being air couplers used with a compressor, they probably consider some leakage as acceptable since they're used with an unlimited source of air..

but, if you haven't figured it out already, much of harbor freight's products are junk to begin with... you really do get wht you pay for.

**Bobby_M** · 11-01-2009, 12:29 AM

I use a similar QD on my setup and it doesn't leak.

shortyjacobs · 11-01-2009, 12:41 AM

I could see "some leakage" as being acceptable, but we're talking a full blast....like ruffle your hair at five paces blast....

**BargainFittings** · 11-01-2009, 01:21 AM

Probably missing the seals on the females. Some one might have liberated them in the store.

**kornkob** · 11-01-2009, 01:31 AM

The problem with HF air parts is that they are cheap-- not inexpensive: cheap. They are 'good enough' for air use but frequently their tolerances are poor.

mordantly · 11-01-2009, 05:18 AM

there CHINESE!!!!!!!!!!!!!! what do you think red china has to offer us? or perhaps your using a 3/8 short in a 3/8 long female. if it can be inserted more than 1/8" past the lock its the wrong one.

Catt22 · 11-01-2009, 08:48 AM

I have had repeated problems with the HB air line QD's and I have only used them for compressed air and never for CO2 for this exact reason. The HB fittings are generally crap. It's hit or miss on these QD's. Some will seal well and others half assed or not at all. I am familiar with the different types and it's not a mis-matched issue. I've totally given up on using them even for compressed air. They are a major PIA and will somtimes spontaneously uncouple for no apparent reason. I would never trust them for use with CO2. I only buy things from HB that are either for one time use or that I can be reasonablly confident that whatever it is won't self destruct before I get my money's worth out of it. It's unlikely something like a plastic tarp will fail. Someone once suggested never buy anything from HB that has more than one moving part or a power cord. I tend to agree with that. I do have a bench top 8" Chinese drill press from HB that I am happy with. I'm out a whopping $69 if it quits on me. No big deal. It's a disposable tool IMO.