Coltri MCH 6 Owners, get in here, this thread is for you!!

You need to patent that with a smiley face on the mallet.
I just rebuilt the top end of stage 2, 3 & 4 on my Daystate/Coltri 230V MCH6 about a month ago. Also had to update the #2 stage with a new piston, seal and valve as the variant I had was discontinued after 6 months of production. These compressors are pretty easy to work on if you have a modicum of mechanical intuition.
When I put mine back together I had the same issue with vibration. Turned out I did not have the bracket exactly correct and once I got all the mounting hardware on and tightened down correctly it runs smoother than it has.
I bought this one used with 50 hours on it and some apparent Bubba handi work performed on it.
Once I got all the work done it is running perfectly and filling my 98 cf bottles in about 10 minutes, maybe 12 from just under 200 bar to 300 bar.
I will never be without a competent compressor again. Getting bottles filled and dealing with cheap compressors is more headache than I care to deal with. All the time I save can be spent shooting.
 
There are bad items that fall through the cracks in everything. I know lots of people that have them and have had no trouble. I like the compressor....and am hoping it will stay going for a long time more.

Mike
100% agree, but if support is willing to toss know defective parts back on the shelf, I'll take a hard pass.
 
Glad I didn't buy one.
I am still glad I have one, still working fine just shakes a little,,,
even if I have to change the 4th stage, still much happier than I was with Yong or Davv
I got mine from diveshop in Spain, so I am probabley out of luck with any warranty

Edit: I found that the welded on bracket that supports the water/air seperator was leaning down hill,, I straightened it out to be true and square with the frame, adjusted the upper support bracket to match the corrected bottom bracket,,, now the tower does not shake like a cat pooping razorblades
 
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I was wondering if any of you has a good solution for a condensate recipient? I made something myself with an empty fuel tank: 2 inlets, and I drilled a bunch of smaller holes for air passthrough. It's working more or less, but when I open the valves too much (or when I forget to close my tank before draining) the big airflow also takes quite a bit of moisture out of the recipient.
So how do you do it? Any better (commercial) solutions?


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Does anyone know if the pressure at which the automatic shutdown kicks in can be modified? I'm not talking about the safety valve but the optional automatic switch.
The unit should shut down at 300 bar according to the specs. When I got my compressor 6 months ago it shut off at 310 bar (which is ok for me, after a bit cooling down it's about 300 bar). But recently I've seen that the pressure has gone up. First 320 bar, today 325 bar. So does anyone know a reason for this shift? And how to bring it down again?

also: my compressor is inside the house in an area which is not heated a lot (a shed). The floor on which compressor and bottle are is rather cold (room 15 degrees celsius, the floor about 10). So in the autumn and summer it's warmer in my shed. Could this influence the auto shut-off pressure?
 
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Does anyone know if the pressure at which the automatic shutdown kicks in can be modified? I'm not talking about the safety valve but the optional automatic switch.
The unit should shut down at 300 bar according to the specs. When I got my compressor 6 months ago it shut off at 310 bar (which is ok for me, after a bit cooling down it's about 300 bar). But recently I've seen that the pressure has gone up. First 320 bar, today 325 bar. So does anyone know a reason for this shift? And how to bring it down again?

also: my compressor is inside the house in an area which is not heated a lot (a shed). The floor on which compressor and bottle are is rather cold (room 15 degrees celsius, the floor about 10). So in the autumn and summer it's warmer in my shed. Could this influence the auto shut-off pressure?
Here's info on adjusting the cutoff pressure directly from Nuvair:
Remove the screw that holds the connector on the top of the switch and use a 5/64 Allen key down through the center, clockwise increases the pressure.
Crack the bleed and adjust until you are at the desired pressure and adjust until the compressor turns off.

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Here's info on adjusting the cutoff pressure directly from Nuvair:
Remove the screw that holds the connector on the top of the switch and use a 5/64 Allen key down through the center, clockwise increases the pressure.
Crack the bleed and adjust until you are at the desired pressure and adjust until the compressor turns off.

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@MikeAllen thanks a lot, this seems to be exactly what I’m looking for. I’ll try it out tonight. Great info 👍👍👍
For reference, I needed a 1,5mm allen key while 5/64 = 2mm. There might be differences between European and American units.
 
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