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Discussion in 'Compressors, Boosters and Blending Systems' started by SurfLung, Mar 21, 2019.

  1. SurfLung

    SurfLung Nassau Grouper

    # of Dives: 200 - 499
    Location: Central Minnesota
    Greasing the RIX SA3
    - As mentioned earlier, I've been doing my grease job at 10 hour intervals instead of the 25 hour interval specified in the manual. From Iain's comments, it sounds like that's not a bad idea. I've been told that the SA6 cowl is easier to get off than the SA3... My SA3 has four hex bolts to remove. I bought one of those low profile ratcheting box wrenches for this and it is now quick and easy to get those bolts off and on.
    - This picture shows the fan in the lower left, the swash plate and turnbuckles in the middle, and the piston rods and cylinders in the upper right. As Iain says, a few pumps of the special grease and then a wipe down to remove the excess. I use q-tips to wipe out the excess grease on the underside which is too narrow of a gap for my fingers and a paper towel.
    - The more difficult part of this greasing is the thrust bearings underneath. You have to put some grease on your finger and wipe it into the bearing surfaces. It goes pretty quick once you've done it a few times. This time around, I think it took less than 15 minutes to take off the cowl, grease everything and put the cowl back on.
  2. iain/hsm

    iain/hsm Manta Ray

    Amen to that brother thats another good point and should be mentioned in the SA-3 manual.
    The other useful tool is a open Half Moon or Obstruction open end spanner for the piston to head clearance when either replacing a new 3rd stage piston and you need to adjust the rod length. You lot will call it by a different name, but similarly if I said crescent wrench we call that an adjustable spanner. Clear as mud I know..

    In the works we use an oil absorbent cloth as they are stronger than paper towels but much more expensive. Another trick is to fold your paper towel 3-4 times into a flat tight band then slip it under the piston rods and it will fit into the groove space between the rod end bearing and the rod/grease holder. You can run it across twice using each edge. Quick and easy to clean the excess grease off the parts, The excess you collect as it can be used for the thrust rider plates.

    One word or caution here, those thrust rider plates are of a super hardened steel and are as sharp as a knife on the leading edges, slicing your finger to the bone becomes noticable only when the blue grease turns red.
    RayfromTX likes this.
  3. iain/hsm

    iain/hsm Manta Ray

    One other point worth consideration is to occasionallly remove the centre bolt and to turn the inner bearing race (the siiver inner part) 30/60/90 or 180 degrees. this presents a "fresh face" to the backside of the rod end bearing housing and ensures even wear over the entire inner race as opposed to wearing just one "face" Contact Area" and allowing excessive wear in one point (at the opposite end from the piston rod) By rotating the race a bit at a time you extend the life of an quite expensive part.

    I would NOT do it every 10 or 25 hours but certainley take a look at 50 and while your at it clean the whole inner race of the rod end bearing and check for wear areas..

    Now here is the kicker.
    DO NOT yank (remove) the whole piston assembly out of the liners, your just cleaning the end bearings, but if you do, dont yank the thing out and be careful not to get grease onto the compression rings.

    Then while you are at it you may as well just replace the piston 0-rings behind the compression rings just on the 1st and 2nd stage (NOT the 3rd) Doing this will extend you compression ring life. Dont do it on the 3rd stage you will damage the rings more by removing them. Just the 1st and 2nd.

    Doing this also help reduce blow by and increases the interstage pressure thus reducing the compression ratio, reducing heat and increasing flow rate.

    Also if you do just change the 0-rings out and put back the old compression rings also check the 0-rings for "scuffing" if you see too much scuffing your not changing them enough conversly when you stop seeing scuffing your changing them too often.
  4. iain/hsm

    iain/hsm Manta Ray

    I know too much info to take in but one other point them I'm done. When you re grease the Rix Both models you notice that the excessive grease "witness" leaking out in your photo is all at the front end.
    Ideally you need it at the back end too where all the thrust is generated, solution is to rotate the pump from TDC to BDC and also mid point with a pump from the grease gun at each point to ensure an even run of grease all around the bearing.
    RayfromTX likes this.

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