YD Scuba Diving Forums banner
1 - 10 of 10 Posts

·
Registered
Joined
·
1,444 Posts
Discussion Starter · #1 ·
I am led to believe that the scubapro mk25 is a good dir reg i.e. ;routing but what about the mk20 also what is a good price for the mk25 second hand .All help is appreciated
Pete
 

·
A Moderate from 04/01/07-24/12/12
Joined
·
11,804 Posts
I am led to believe that the scubapro mk25 is a good dir reg i.e. ;routing but what about the mk20 also what is a good price for the mk25 second hand .All help is appreciated
Pete
Hopefully NickB will be along cos he is chapter and verse on this.....

The MK20 is essentially a MK25 without the ability to alter the IP from the outside. There was also something about the design which meant you can cause damage if you are a hamfisted service agent....plus a different material used for the piston I think.

My stage regs are MK20 and AFAIAC offer a very economical alternative to the MK25....they are often cheap on eBAY.

It is possible to buy the parts to convert a MK20 into a MK25.

HTH
Mal
 

·
Registered
Joined
·
13,519 Posts
I don't know for sure Pete but isn't the Mk20 and the Mk25 shape so routing should be similar.

I bought the Mk25 and they are indeed lovely :)
 

·
Registered
Joined
·
1,222 Posts
I am led to believe that the scubapro mk25 is a good dir reg i.e. ;routing but what about the mk20 also what is a good price for the mk25 second hand .All help is appreciated
Yes, Mk20 or Mk25 are ideal. The only thing bad about them is the price.! Don't buy new, get them on ebay. They make excellent stage regs too.

Bob
 

·
Utrinque Paratus
Joined
·
6,077 Posts
Here you go

 

·
Registered
Joined
·
11,575 Posts
The MK20 is essentially a MK25 without the ability to alter the IP from the outside.
Spot on. The Mk25 evolved from the Mk20 with the addition of an IP adjustment (sort of). Really, you don't get much adjustment; plus/minus one bar is about it. Major adjustment is still done by adding or removing shims inside the reg, but once it's set (in the factory), it doesn't shift by much.

It continues to evolve: the ambient pressure holes have gradually elongated, the piston is now a composite plastic affair, rather than brass and it also has a much sharper HP end and an anti-freeze teflon coating. The ambient pressure chamber is now ribbed, not for extra pleasure, but for improved anti-freeze characteristics (hence the Mk25AF name).

It is possible to buy the parts to convert a MK20 into a MK25.
Correct, but buying a Mk20 and all the parts you'd need to convert it to the latest Mk25 spec would cost more than buying a Mk25 to start with. The new piston is a very worthwhile upgrade and your service technician should swap it out for free during a service. I service my own and my LDS will swap an old brass piston for a new one for free.

I use Mk25AFs for my backgas and Mk20s for my deco regs.

I may try to gather together some images of the various generations of Mk20/25s to aid identification.

Watch this space.....
 
1 - 10 of 10 Posts
Top