12jc pump rebuild

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bobjthomson

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« Reply #25 on: August 31, 2017, 12:01:30 AM »



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connorstexas

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« Reply #26 on: August 31, 2017, 10:41:47 PM »
can a jc pump pump be opened up a little but on the nozzle side like a dominator can for some extra flow?


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Flusher

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« Reply #27 on: September 01, 2017, 09:59:21 AM »
can a jc pump pump be opened up a little but on the nozzle side like a dominator can for some extra flow?


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What is happening inside the old style Dominator bowls, when opening the exit side, is the volume is opened ro form a pressure chamber.

If you look at a section of a pump, you can see that a venturi shape is designed into all of the components.  The intake opening reduces in cross-sectional area through the impeller and the transition into the bowl.  Then gradually expands at the exit side of the bowl/droop, allowing the water to slow and build pressure.  Pressure is the result of restriction to flow.  This restriction is ultimately the nozzle and it is this point where the pressure is converted into thrust.  The C bowl doesn't lend itself to this modifications without extensive cutting, welding, and fabricating.

The next problem that you will encounter is the nozzle o-ring in the steering socket.  If the opening is made too big, the o-ring will be uncovered when turning.

The ideal is to have a balance of all of the components in the system.  Unfortunately there is no five minute modification that will net a performance gain.

It is definitely worth keeping your bowl and impeller tuned up.
"I want to roll with my brother Joe" - Joe Bateman - January 29, 1950 ~ November 27, 2013

 


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