GX-CS4 "GREASE POT" ?

Airgun Al

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3 questions on the GX CS4 compressors:

1. Why the 4 rubber feet, on the SIDE of the unit? Are they suppose to run on their side, bottom, or does it matter?
2. Grease is VERY thick. What pulls or push's grease to the bearings? Besides twisting the knob occasionally, is there something mechaniclly pulling or pushing the thick grease? It seems like gravity alone, would not provide enough grease to critical areas that need the lubrication.
3. "GREASE POT"...Exactly what bearings get fed by the grease pot? I assume it feeds 2 different crankshaft bearings. Does it feed any other bearing surfaces?
 
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3 questions on the GX CS4 compressors:

1. Why the 4 rubber feet, on the SIDE of the unit? Are they suppose to run on their side, bottom, or does it matter?
2. Grease is VERY thick. What pulls or push's grease to the bearings? Besides twisting the knob occasionally, is there something mechaniclly pulling or pushing the thick grease? It seems like gravity alone, would not provide enough grease to critical areas that need the lubrication.
3. "GREASE POT"...Exactly what bearings get fed by the grease pot? I assume it feeds 2 different crankshaft bearings. Does it feed any other bearing surfaces?
1. Correct. Can run either orientation. That's why the water sight glass is designed as it is, to ensure you have enough water in it when it's on its side.

2. The grease never touches the bearings. It is pushed/sucked into the gap between the piston and cylinder wall and is spread by the rubber seals. (The only bearings are on the crankshaft under the cylinder assembly)

3. See #2.
 
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Lubrication occurs similar to nasal spray via inhalation. It coats as it’s inhaled into the moving parts. Seems iffy but a lot of compressors using that design work pretty well.
Doesn't take much, since there is no metal-to-metal contact, only rubber-to-metal. Just have to keep the rubber from drying out is all.
 
This nasal spray system....Does that also lubricate the crankshaft bearings?
Asked and answered above...

NO

The ONLY way to grease the needle bearings in the crankcase is to disassemble the unit and apply grease manually. If you see my pictures in the "adding water" thread, you'll quickly see why.

 
Asked and answered above...

NO

The ONLY way to grease the needle bearings in the crankcase is to disassemble the unit and apply grease manually. If you see my pictures in the "adding water" thread, you'll quickly see why.

I see your post and photos.
Very well described, thank you.
Exploded diagrams seem to be top secret, so its nice you took the time to open the hood, and evaluate.
So, I see that the grease pot, only lubes the top end of the pump.
Whats your thought on the lower crankshaft bearings only receiving lubrication once, when assembled?
Do you think one, single application of grease, will be adequate for a long life, of the crankshaft and both bearings?
Any idea how many RPM's the crank turns, when under load?
A bath of oil, and a "slinger" style spoon, to throw oil across the bearing surfaces, similar to antique lawn mower engines, seems like a better idea.
That would be a very easy and inexpensive way, to constantly lube the crank bearings, thus prolonging the lifespan of crankshaft,
What are your thoughts, after seeing it in person?
 
I see your post and photos.
Very well described, thank you.
Exploded diagrams seem to be top secret, so its nice you took the time to open the hood, and evaluate.
So, I see that the grease pot, only lubes the top end of the pump.
Whats your thought on the lower crankshaft bearings only receiving lubrication once, when assembled?
Do you think one, single application of grease, will be adequate for a long life, of the crankshaft and both bearings?
Any idea how many RPM's the crank turns, when under load?
A bath of oil, and a "slinger" style spoon, to throw oil across the bearing surfaces, similar to antique lawn mower engines, seems like a better idea.
That would be a very easy and inexpensive way, to constantly lube the crank bearings, thus prolonging the lifespan of crankshaft,
What are your thoughts, after seeing it in person?
Well, I was skeptical at the design of a compressor without an oil bath, I'll admit. But after taking it apart, and seeing how it was designed, I am confident it is a solid design. The motor RPM is 2700, and the crank is about 105 RPM. Very low, won't be slinging the grease off. And the lack of oil allows the compressor to be operated in ANY orientation, which is a nice feature (don't try to run it upside down, as the coolant system cannot work that way).

While I think it's a good design, there SHOULD be a maintenance schedule for ANY moving machine that isn't auto-lubed. I plan to take mine apart every 25 hours or so and see how it looks inside the crankcase and piston. The good news is that the silicone grease they use is VERY sticky, and the temps inside the crankcase will be VERY low due to low RPMs, so perhaps it will last a very long time. More to follow in my thread as time goes on.
 
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Well, I was skeptical at the design of a compressor without an oil bath, I'll admit. But after taking it apart, and seeing how it was designed, I am confident it is a solid design. The motor RPM is 2700, and the crank is about 105 RPM. Very low, won't be slinging the grease off. And the lack of oil allows the compressor to be operated in ANY orientation, which is a nice feature (don't try to run it upside down, as the coolant system cannot work that way).

While I think it's a good design, there SHOULD be a maintenance schedule for ANY moving machine that isn't auto-lubed. I plan to take mine apart every 25 hours or so and see how it looks inside the crankcase and piston. The good news is that the silicone grease they use is VERY sticky, and the temps inside the crankcase will be VERY low due to low RPMs, so perhaps it will last a very long time. More to follow in my thread as time goes on.
Thanks for your indepth research and evaluation.
 
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Here's what the inside of my grease cup looks like. The grease is over 1 cm below the lip. If I followed the directions no grease would be injected into the pump for more than 30 hours. I don't think that is the intention. So I would advise as others have mentioned to check your grease cup and turn it until the grease is level with the edge. Also the grease does not appear to be silicone grease because I put some of my finger and it easily washed off with normal soap. Real silicone grease does not wash off with soap. It took nine turns to level off the grease to the edge of the grease cup

PXL_20240329_234550931.jpg
 
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The ding isn't normal, but you can fix that with some needle-nosed pliers very easily.

The seal part is normal. Sometimes it comes out with the pot, sometimes not. Put the seal back in the machine and carefully seat it so that it forms a little dome pointing upwards.

Then screw the inner knob while holding the outer pot, and proceed to level out your grease. Once it's level, turn the knob backwards 3 clicks, reinstall the pot, then turn the knob clockwise two turns (if you feel a little resistance, stop and leave it there until you hit the next 10 hours).
 
The ding isn't normal, but you can fix that with some needle-nosed pliers very easily.

The seal part is normal. Sometimes it comes out with the pot, sometimes not. Put the seal back in the machine and carefully seat it so that it forms a little dome pointing upwards.

Then screw the inner knob while holding the outer pot, and proceed to level out your grease. Once it's level, turn the knob backwards 3 clicks, reinstall the pot, then turn the knob clockwise two turns (if you feel a little resistance, stop and leave it there until you hit the next 10 hours).
Thanks, but I’ve tried to turn that knob and it won’t budge and I shouldn’t need to use pliers and risk more damage as it’s just aluminum. I’ll need to take another pic later but it seems the side that’s booggerd up is razor thin as if the cup was cut offset to one side. I have sent a message to ANKUL that is the seller on Amazon.
 
Thanks, but I’ve tried to turn that knob and it won’t budge and I shouldn’t need to use pliers and risk more damage as it’s just aluminum. I’ll need to take another pic later but it seems the side that’s booggerd up is razor thin as if the cup was cut offset to one side. I have sent a message to ANKUL that is the seller on Amazon.
Yes, it IS very thin. That's why I suggested needle-nosed pliers to re-bend the spot back to round again so that the knob will turn. But perhaps it's best to wait for GX to get back to you and see what they offer.

Have you tried to turn the knob counter-clockwise while holding the outer casing with a rag? Maybe you can back it up enough smooth out that bent part?