My GX CS4-I
- Thread starter F6Hawk
- Start date
Got the PM and replied. Still don't understand why you don't simply state that here in public.
All my best!
Kerry
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Here is the link to the pump I got from Amazon that is the same as what comes in them from GX
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I want to thank you for showing this. This post just fell into my lap right time right place. My Omega trailer charger has been not pumping correctly, I call it flat line about 2000 psi. Worked fine all last summer then this problem started. DH test was 3 minutes for 4500 psi.Gonna decide which one I like better, and let the other one go to a better home. That's the plan for now, anyway.
I ordered a GX CS4 the CS4-I wasn't available from Amazon. Thinking I probably won't get the trail charger back in service. Newbie to this sport and want to learn all I can. Machinist and gun smith for several years I want to be able to fix things myself.
So, I took it apart to see what could be done with the rebuilt kit. The first thing I noticed was all the grease under the head as you show. I was thinking that I had added too much grease causing the problem. The only useable parts in the rebuild kit was two Delrin split rings for the piston. The other, I'll call them sleeves brown material were too large ID and OD. So, my only option was to clean everything well, be more sparing with grease, "I think I injected too much grease so I'm little leery." I cleaned all the excess grease under the grease pot top of head and sparingly wiped some grease around that area. But now looking at your picture I don't know if I need to add more grease.
I haven't put it all back together yet so I'm asking what do you think?
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For certain, too much grease WILL cause these things to struggle to produce pressure. I'm betting that by cleaning the bulk of the grease out, you will solve your own problem. I'd clean all three cylinders, and leave just a trace of grease inside each one.
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I keep seeing a lot of confusion about SCBA tank life and certification, so I though I'd throw some info here in my thread about the process. Bear in mind, this is to keep a SCBA tank LEGAL to fill by a legit commercial air shop.
SCBA tanks when made have a useful life of 15 years, with hydrostatic testing required at 5 & 10 years of age. On it's 15th birthday, it is done for. Unless...
At 15 years of age, they can have a life-extension test done to them (Modal Acoustic Emission, or MAE) by a company called Hexagon Digital Wave, but it's pricey. $375 plus shipping both ways the 5th year, then $110 the next two 5-year cycles plus shipping both ways on your dime. That's $595 plus 6 shipments; assuming each is $40 (probably on the light side), that's a grand total of $835 to get an extra 15 years of LEGAL use out of the tank.
hexagondigitalwave.com
SCBA tanks when made have a useful life of 15 years, with hydrostatic testing required at 5 & 10 years of age. On it's 15th birthday, it is done for. Unless...
At 15 years of age, they can have a life-extension test done to them (Modal Acoustic Emission, or MAE) by a company called Hexagon Digital Wave, but it's pricey. $375 plus shipping both ways the 5th year, then $110 the next two 5-year cycles plus shipping both ways on your dime. That's $595 plus 6 shipments; assuming each is $40 (probably on the light side), that's a grand total of $835 to get an extra 15 years of LEGAL use out of the tank.
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Same blue filter setup as in poet 43. With the filter inline the GX will only fill to 150 bar. Can't hear air leaking anywhere. Where all should O rings be in filter?
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Doing this from memory, but...
One big o-ring under end cap that screws off. One each white nylon under each Foster fitting. One smaller o-ring inside where the plastic holder fits onto the end cap. Haven't had burst disc off to see what's under there.
Most common leak I find is the bleed valve on the compressor itself.
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Build some pressure, then spray soapy water on all the fittings. Fosters can leak around the threads or via a nicked o-ring. End cap needs to be tightened until you feel the resistance of the o-ring, then perhaps a bit more to fully seat. But DON'T crank it down tight, as the pressure will cause it to jam up and be hard to remove.
If you build to 150 can can't find it with soapy water (by burst disc leaked, had to tighten it a bit), turn off the compressor but leave the pressure and listen for air. Should be easy to find if you know it's in the filter itself.
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Pulled it all apart to make sure everything was there. Tightened all back up and seems fine now.
Thanks
Thanks
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Kudos to @Humdinger for compiling multiple posts about air tank sizes, volumes, as well as air volume. Since I think so highly of his efforts, I am re-posting them here in case anyone searches for AIR TANK VOLUME or SCBA TANK SIZE, or 88 CU FT or 97 CU FT or 9L. (The first two parts are his, the last is mine. All in an effort to reduce confusion as to SCBA air tank sizing)
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GX factory literature rates the GX4 and GX4-1 air output rating at 11 liters per minute at 1 bar. That equates to 22 liters per hour @ 4500 psi or 310 bar.
Most owners fill their SCBA tanks to 310 bar. That means a 6.8 liter tank X 310 bar holds 2108 liters of air @ 4500 psi. It takes 3 hours 12 minutes to fill a 6.8 liter tank from 0 to 4500 psi using the factory advertised fill rate.
A 9 liter tank holds 2790 liters of air at 310 bar or 4500 psi. That means using the factory rated output of 11 liters per minute it takes 4 hours and 13 minutes to fill a 9 liter tank from 0 to 4500 psi using a GX CS4.
A 500cc cylinder holds 125 liters at 250 bar. Filling a 500cc PCP air cylinder to 250 bar takes 11 minutes 22 seconds from empty.
Output air filters and other variables may affect these fill times slightly but this gives a general idea of the fill rates for this compressor. Code:
SCBA tank terms are bandied about that can be confusing and rather inaccurate. There is technically no such thing as an 88/97/100 cu ft SCBA tank, though those (marketing/advertising) terms are commonly used (and confusing for people, old pros and newcomers alike). Some also refer to SCBA tanks by their breathing time (which makes zero sense for us, since we aren't firefighters, and time is irrelevant, since it all comes down to one's lung capacity and level of exertion).
Four common sizes of SCBA tanks (yes, there are several more, depending on whom makes the tank) are below. The first two values are actual WATER VOLUME measurements, and are actually the best way to compare sizes, since water isn't compressible, and air is. The other two are kind of thrown about with less precision by various groups:
114 cu in (1.9L) <20 cu ft> <15 minutes?>
285 cu in (4.7L) <45 cu ft> <30 minutes> Actually holds 1,457 L (51 ft^3) of air @310 bar.
410 (6.7L) < 60/73 cu ft> <45 minutes> Actually holds 2,077 L ( of air @ 310 bar; 1,675 L (59 ft^3) of air @250 bar.
550 cu in (9L) <88/95/97 cu ft> <60 minutes> Actually holds 2,790 L (98.6ft^3) of air @310 bar, 2,700 L (95.3 ft^3) of air @300 bar (you get the idea).
The reason for the various cu ft numbers is because air is compressible, so depending on pressure, one can have more or less of an air volume.Upvote 0