Need Hypro 403 pump help! (oil)

Discussion in 'Pesticide & Herbicide Application' started by GREENITUP, Feb 18, 2013.

  1. GREENITUP

    GREENITUP LawnSite Member
    Posts: 245

    Pump and sprayer worked fine last week... but today was 25 degrees and I think the pump may have got some ice inside. The oil going to the diaphrams (where you fill the clear, plastic cup/gage) started disappearing. It wasn't milky like when the diaphrams crack and mix with water..... it just keeps getting sucked into the pump. I've refilled it 3 or 4 times while running and it just keeps going out.... it's not leaking on the outside. Diaphrams were replaced about 1.5 years ago with little use since. Any ideas?????
     
  2. dwmason

    dwmason LawnSite Member
    Posts: 70

    The ice has done one of two things - displaced one of the diaphrams or one of them has split. Most of those diaphrams seem to only last a year or two.
     
  3. GREENITUP

    GREENITUP LawnSite Member
    Posts: 245

    Thanks DW.... why do you think the remaining oil isn't getting milky as the pump runs? can it flow one direction and not the other? I just tinkered with it again - it is even sucking the oil down after you cut off the engine!
     
  4. phillie

    phillie LawnSite Senior Member
    Posts: 861

    Have you taken the diaphragms out and checked them? That oil has to be going somewhere, if its not leaking on the outside then its leaking on the inside. I would bet money that it is a diaphragm issue as there isnt much more to blame.
     
  5. robert@rittenhouse

    robert@rittenhouse LawnSite Member
    Posts: 52

    The other potential issue, the frost put a crack in the crank case. Therefore the oil is going around the diaphragm. It could be a tiny hairline crack and is only opening up when under pressure. So when you open up the pump look for a tiny crack in the crankcase if you find that the diapragms look ok.

    Unfortunately, frost is the death of many pumps.
     
  6. doug1980

    doug1980 LawnSite Senior Member
    Posts: 276

    This just happened to me. Replaced the diaphragm and all is good. I didn't see a crack on it but the problem was solved.
     
  7. Landrus2

    Landrus2 LawnSite Platinum Member
    Posts: 4,811

    Do you guys get freezing temperatures down there:waving:
     
  8. robert@rittenhouse

    robert@rittenhouse LawnSite Member
    Posts: 52

    Good.

    It is a really important to keep an eye on that oil sight glass. If the oil turns milky grey, stop pumping and change the diaphragms right away. Even with a torn diaphragm it will continue to pump. But you are lubricating the pump with spray material and not oil. Eventually the pump will heat up, and the metal will break down and the pump will seize up. Then you will need a new pump.

    Smart landscapers keep a spare set of diaphragms in stock. ;-)
     
  9. doug1980

    doug1980 LawnSite Senior Member
    Posts: 276

    A few nights it does freeze here.
     
  10. robert@rittenhouse

    robert@rittenhouse LawnSite Member
    Posts: 52

    It is unfortunate that you don't get to put the sprayer in storage for a few months and winterize it properly. You could be spraying one week, then get a frost the next week. Hard to plan for that.
     

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