More MCH 6 questions (quietening, filtering and time to fill)

[Tony Pr]

Good afternoon,

A few more questions after getting my MCH-6 to run ok and pump a few tanks. Thanks for all the advice previously, has made me feel a lot better about using it properly.

How to make MCH 6 less noisy? Thought of putting it on a rubber mat and putting rubber washers on either side of the bolts between washers which hold the compressor section to the chassis. Other option could be building a box for it, similar to the MCH6 silent? The worry with that would be airflow, however, could create some form of a tunnel for it to channel through and out. Perhaps an auxillary fan to make sure?

Currently it takes 35 mins or so to fill a tank. That is a 11 litre tank from 50 bar to 200 bar. I have checked it for leaks and have found none, I purge every 10 mins, just enough to collect all the water out. There is no drop in RPM of the 3hp (2.2kw) electric motor so I assume that it is either the 4th stage piston being worn, the rings or the valves as the intake is not clogged and the intake hose is not kinked. That is according to the manual. Is there any easy way to work out which stage is not functioning well or if the 4th stage needs replacing without taking it all apart? I thought that measuring temperature on each stage will confirm if they are each working well.

Given the compressor is 20 years old and probably has never had a 100 hour service I would say that the service would be the next logical step. I have not done this as yet as I wanted to make sure that it was working well enough to invest in doing this and get a few dives off the tanks in first. Is there any harm in it taking a bit longer to fill tanks (apart from my power bill) haha?

Additionally I have sourced some 13X and AC to repack a filter. It came out of Bauer plastic containers and is now stored in airtight containers. I am worried that the 13X has adsorbed some moisture and will not be as effective. I am unsure of the age, but could probably do with a bit of a dry out before use. I was planning on putting the amount I planned to use in the oven for an hour or so on 120 or so degrees. Then straight into the filter and into the compressor. I have been reading up on the topic on this forum, ( including 13X molecular sieve storage life) however, have not found a definitive answer if this is worthwhile doing. Is it worthwhile doing? I plan on changing the filter well before it is calculated to be due.

Thanks.

 

[rjack321]

Good afternoon,

A few more questions after getting my MCH-6 to run ok and pump a few tanks. Thanks for all the advice previously, has made me feel a lot better about using it properly.

How to make MCH 6 less noisy? Thought of putting it on a rubber mat and putting rubber washers on either side of the bolts between washers which hold the compressor section to the chassis. Other option could be building a box for it, similar to the MCH6 silent? The worry with that would be airflow, however, could create some form of a tunnel for it to channel through and out. Perhaps an auxillary fan to make sure?

Currently it takes 35 mins or so to fill a tank. That is a 11 litre tank from 50 bar to 200 bar. I have checked it for leaks and have found none, I purge every 10 mins, just enough to collect all the water out. There is no drop in RPM of the 3hp (2.2kw) electric motor so I assume that it is either the 4th stage piston being worn, the rings or the valves as the intake is not clogged and the intake hose is not kinked. That is according to the manual. Is there any easy way to work out which stage is not functioning well or if the 4th stage needs replacing without taking it all apart? I thought that measuring temperature on each stage will confirm if they are each working well.

Given the compressor is 20 years old and probably has never had a 100 hour service I would say that the service would be the next logical step. I have not done this as yet as I wanted to make sure that it was working well enough to invest in doing this and get a few dives off the tanks in first. Is there any harm in it taking a bit longer to fill tanks (apart from my power bill) haha?

Additionally I have sourced some 13X and AC to repack a filter. It came out of Bauer plastic containers and is now stored in airtight containers. I am worried that the 13X has adsorbed some moisture and will not be as effective. I am unsure of the age, but could probably do with a bit of a dry out before use. I was planning on putting the amount I planned to use in the oven for an hour or so on 120 or so degrees. Then straight into the filter and into the compressor. I have been reading up on the topic on this forum, ( including 13X molecular sieve storage life) however, have not found a definitive answer if this is worthwhile doing. Is it worthwhile doing? I plan on changing the filter well before it is calculated to be due.

Thanks.

if you are just trying to rejuvenate 13x that is unused but stale in the original container that's fine. I would not trying to reuse it from the actual compressor however.

here's some guidelines on how long and hot you need to bake it to get the water to boil off.
How to Rejuvenate Indicating Bulk Silica Gel and Molecular Sieve

do not under any circumstances put an insulated box around your compressor unless you install an air conditioning unit in the wall of the box as well. It will overheat, the oil will partially combust, you run the risk of CO poisoning, all the metal parts will be way more stressed and overheated, just dont even think about it.

 

[tbone1004]

I would recommend doing the full service sooner rather than later. You have something leaking on the interstages, and as we said before you need to check interstage pressure to validate which one is leaking backwards.

On quieting it down. The fans on most of these compressors are very loud. They're quite slow RPM, and because of that, have very aggressive blade pitches. If you remove the stock fan and replace it with an electric fan, that will help significantly.
The first thing I would do is look at the intake filter. Most people don't realize how much of the noise from compressors in general actually comes from the intake filters *this is why your cars is inside of a box*. If you look at a higher quality and larger intake filter, particularly one designed to quiet a compressor down, you'll be much better off. Solberg makes good ones.
One like this will make a massive difference. I would recommend sizing this with one that is at least one step larger than your inlet hose, i.e. if you have a 1/2" hose into your compressor, get a 3/4" or a 1" filter.
https://www.amazon.com/Solberg-FS-1...9ABKM6TRFQA&psc=1&refRID=EXB9M01BN9ABKM6TRFQA

 

[Tony Pr]

Thanks @tbone1004 and @rjack321 . I will have a read of how to rejuvenate and look at an oversized air intake.

In terms of checking Interstate pressure, how does one do that on an MCH6? The only gauge is the pressure gauge at the top of the moisture separator.

 

[rjack321]

In terms of checking Interstate pressure, how does one do that on an MCH6? The only gauge is the pressure gauge at the top of the moisture separator.

Basically you don't. If its not working adequately you have to go by the behavior or take it apart.

 

[rcontrera]

Do not put rubber washers on any of the bolts. While it may cut down on noise, it will also allow some movement of those bolts and that can lead to breaking supports and braces.