Coltri pressure maintaining valve, does it work properly?

[Agro]

At least in the old MCH-6 compressor filter tower, the design does not support PMV use. The pressure goes past the O-ring. A slightly larger O-ring might help. I replaced the filter tower; after that, it works well. Looks that Coltri's filter tower tolerances are varible becase all users does not have same problem.

Oh yes, that's an other problem. I have the old Coltri filter tower and added the (new) PMV. In the beginning it worked well, then the lower o-ring broke. Never seen this kind of o-ring dammage, it seemed to be cut. No superficial dammage but clear cut. I measured an found out tower's sealing surfce is a bit lower than PMV's o-ring groove. O-ring is "sealing" on cone (leading to sealing surface) that's not good at all, we have a gap which of couse kills the o-ring. A larger o-ring is not the solution, gap is the problem. Thank to my lathe I was able to make the PMV fit, now o-ring is on sealing surface.

This has nothing to with the other problem: PMV itself is leaking a little bit. I had a closer look to the sealing insinde the PMV, its metal to metal. In my opintion this can not seal completely. No teflon seat, no o-ring, just metal to metal.

It seems Coltri is accepting a small blow by which of course leads to draining the filter after use. This leads to unneccessary load change and a filter tower without pressure. Nobody wants this, Grantmac described the reason why.

So it seems I have to live whith this blow by.

I hate Coltri.......

 

[CG43]

This has nothing to with the other problem: PMV itself is leaking a little bit. I had a closer look to the sealing insinde the PMV, its metal to metal. In my opintion this can not seal completely. No teflon seat, no o-ring, just metal to metal.

Bravo, that's the cause!
And now look at the air flow diagrams of all the small Bauer compressors .
Is there a non return valve between the filter and the third stage outlet valve ? NO !!!

So only the third stage outlet valve prevents the air from flowing back from the filter into the compressor. The compressor itself is not 100% tight.
The 3rd stage outlet valve seals just like the Coltri PMV metal to metal and it is naive to assume that any Bauer 3rd stage outlet valve will hold pressure for days or weeks.
Bauer does not consider it necessary to install a check valve in its small compressors even though it is cheap and easy to install.
If you fill tanks once a week, it doesn't matter if the pressure drops within 7 days or just one hour. The important thing is that the filter pressure does not drop significantly below PMV pressure during the cylinder change, which takes about 2 minutes.

 

[grantmac]

My Bauer has a check valve between the oil separator and filter stack (which holds pressure for weeks.

 

[Wookie]

My Bauer has a check valve between the oil separator and filter stack (which holds pressure for weeks.

He's talking about the triplex, which comes on the crappy Bauers, not a real compressor.

 

[CG43]

He's talking about the triplex, which comes on the crappy Bauers, not a real compressor.

The first is correct , and other older small Bauers don't have a non-return valve either.
Since you are of the opinion that these are not real compressors, you will surely be able to answer my question that I asked in the K14 thread , because this is a possible point of criticism .

If the bauer company recommends cold starting petrol engines with an empty filter, the occasional build-up of pressure in the filter cannot be as catastrophic as some people here are telling us.
If you were abel to examine it closely, you might find that the additional amount of water that the filter receives when starting from low pressure to PMV pressure (PMV closed) corresponds to a running time of 20 minutes.

Anyone who knows more about this, I am interested.

This time it is not a question about the mechanical load cycles, but only about the additional amount of moisture in milligrams or running time.
Of course we can also talk about other points of criticism that justify your judgment.