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farmerboybill

Can I neck a 2 inch pump down to 1 inch?

farmerboybill
15 years ago

Hey all,

I want to be able to run a sprinkler on my rain barrels. I was looking for a one or one and a half inch pump but came across a killer of a deal on craigslist for a 2 inch pump. Would I fry the seals in the pump if I necked the inlet down to one inch, like the valves on my rain barrels?

{{gwi:313395}}

Comments (9)

  • canguy
    15 years ago

    It will work but you will not be able to run the engine at full throttle. The pump will cavitate.If the pump is electric drive, don't do it.

  • golfer_2008
    15 years ago

    Cant say for sure without seeing the performance curve for your impeller pattern but you can give it a try. Just start it up and feel the casing.If it starts to get warm you can shut down. The restricted flow will no doubt lower the horspower required.

  • farmerboybill
    Original Author
    15 years ago

    The pump has a 3 horse flat head briggs. It is only governed, no throttle. I can get it to run at and idle by pushing the throttle butterfly with my finger. I guess it wouldn't be that hard to rig up some sort of linkage to run it at an idle. I think it's set up to only run at half throttle anyway. For 20 bucks, if I fry it, I guess I'm not out much, eh?

    Thanks for the input so far.

  • lbpod
    15 years ago

    Couldn't you just tie all the one inch outputs into
    a 2 inch, (or larger), pipe, (sort of like a manifold)?

  • metal
    15 years ago

    Isn't the idea behind rain barrels to save money? Won't the gas used for the pump outweigh any savings you get from gathering rain? Not trying to be a smart arse, just wondering. Around here water is CHEAP.

  • tomplum
    15 years ago

    My thought would be plugging the sprinklers w/ debris from the barrels. I'm also guessing that it isn't the right pump for the job.

  • broke_not
    15 years ago

    It will work.....for a little while. If you're necking down the output port in an attempt to add some pressure for the sprinkler application, then you're likely going to exceed the psi, (or "head"), rating the manufacturer specifies for the pump.

    FWIW, all of the pumps we have in the rental fleet that have been "converted" by customers to do jobs they weren't designed to do always wind up in the shop.

    Take a peek at some of the pumps for sale at places like Northern Tool. There are pumps specifically designed for higher pressure applications. Many such sites include links to parts breakdowns and such....you can see what allows higher pressure pumps to last in such applications.

    Here's some info on converting manufacturers' "head" and "psi" ratings back and forth:

    ;-)

    Here is a link that might be useful: Head to PSI

  • farmerboybill
    Original Author
    15 years ago

    Hey all,

    Thought I'd follow up on one of my old posts -

    Thanks for everyone's input. I took all your advice and trashed my water pump idea.

    What I did was get bigger diameter hose. With some inch and a half sump pump hose, the flow was very good. Obviously, I didn't have it hooked to a sprinkler, I just moved it from plant to plant through a dry spell.

    Now, it's the DEAD cold of winter here in Wisconsin and I'm fondly remembering my garden on the past year and dreaming of the garden of the next...

  • HU-654401185
    3 years ago

    Something that works well is to install a recirculating loop with a throttling valve into the system. The discharge would be connected back into the suction line with a valve to allow you to control how much flow is truly discharged vs recirculated to alleviate the pressure.