¤ Repairs and Servicing ¤




    Servicing Hy - Flos:

      If your old pump is running slowly or noisily, it is possible that it's performance may be enhanced with a decent service. Depending on model type and condition, we will happily service your pumps.

      Unfortunately, we cannot currently provide a cleaning service for the main body of your pump - we suggest that you try using a light solvent for removing any oil residue on the paint-work.

    Some Useful Tips :

    Keep and run your pump on the flat. Try not to leave it running when tilted as this will add wear to the bushes on the main pump shell.

    To reduce noise:
      1. Place a small piece of carpet under your pump - this will make it even quieter than before.
      2. Partially undo the two flat-headed screws that secure the airplate to the main shell of the pump. Readjust the position of the airplate until the pump runs at its quietest, then tighten the screws again.

    Balance out the back pressure on the pistons by combining the piston outputs.
       This will:
      1. Ensure that your pump runs more efficiently.
      2. Balance out the stress on the pump, in particular the part of the piston that articulates within the airplate. Otherwise this can eventually become ovoid, the pump will become noisy and possibly fail.
      3. Balance out the amount of wear on the piston itself, reducing the likelihood that one of its components (upstroke/downstroke) will fail.

    To increase airflow:
      1. Use a new / clean airstone.
      2. Remove oil and other built-up material from the airholes on the airplate and, if clogged, from the corresponding holes on the piston itself. You can use the end of a paperclip for this.
      Please Note: Occasionally for old pistons, it may well be the case that the aforementioned build up of dirt and oil within the piston is itself helping to maintain the airtight seal necessary for the pump to function. If this is the case, this piston may well stop working properly if cleaned in this manner.

    Do not over-oil the pistons. However, always maintain some lubrication on the crank tip which connects the flywheel to the top of the piston, as indicated by the arrow in the image below.


    Atmospheric changes: if your pump unaccountably starts making more noise than usual, please note that the behaviour of some pumps, particularly those with solid cylinder series I pistons, can change with the weather, especially in response to big swings in (a) humidity and (b) barometric pressure. As long as your pump is set-up and maintained correctly, the noise should lessen as the pump adjusts to the changes.

If you have any further tips you feel may be of assistance, please feel free to contact us via email using the address at the bottom of the page.


    Repairing Hy - Flos:

      Depending on availability of parts and the nature of the problem, we may well be able to repair your broken pump.

      We can repair:
        Broken motors
        Mis-aligned (rubbing) fly-wheels
        Broken Bushings
        Broken Pistons
        Snapped off / missing outlets


Whatever the problem, we will try our best to help.
Please contact us via email at:




- site last updated : 26 March 2024 -
- all content and images protected by copyright - ©mmxix

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