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New 2nd Stage Valves

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  • New 2nd Stage Valves

    MCH 5 is not mentioned, only MCH8-11-13-16-18 however Coltri never do. I suspect this applies. Tried to post a direct link, however this board will not permit this. Go to Coltri, look under 'News'.

    Have to say, ever seen much wrong with my current valves, but hey ho, what do I know?
    Last edited by BritCNGUser; 05-20-2017, 02:53 PM.

  • #2
    I see new 1st stg valve and new 2nd stg piston assembly

    heres the valve
    Last edited by trdscfjc; 05-16-2017, 11:54 PM.


    • #3
      Not sure what is wrong with the second to need any improvement, they know best? However, minor niggle since fitting the 'Red' third is that until pressure is high enough to hold third intake closed the 2nd climbs to about 35Bar before it dives back when the third inlet seats, but that is all. At least I assume that is what is happening here. See video.

      Only happens at start-up, so I live with it.

      Perhaps related, see atttached piccy - I notice when I attempt to lap the intake third, on a very fine flat stone, I get this. The inner ring is not on the same 'plane' as the outer - and I have two valve sets like this, so assume this to be intentional.
      Attached Files
      Last edited by BritCNGUser; 05-20-2017, 03:01 PM.


      • #4
        That difference is not intentional. Coltri stood by this, sent me a replacement set. It's a machining error. I have to say whenever Coltri haver been at issue they have always come good without quibble.