[Thirsty_Monk]

Dear Sally,

I bought fairly expensive 50 GPM pump and I run it for couple of months.
Pump is hard to prime.
It leaks whenever it wants (or sometimes it does not leak at all).
if it pumps 30 GPM than that is a miracle.
What to do?

Your truly
Frustrated with pump.

[tschmidlin]

Dear FWP,

Do you have any pictures of how you have it hooked up?

[punatic]

Two words:  Boat anchor...

[punatic]

But seriously folks - 50 gpm against how much head?  Did you look at the pump performance chart to make sure you had the right pump for the job?   Is it still under warranty?

[Thirsty_Monk]

Thank you for suggestions guys.
I bought this pump:
http://www.mcmaster.com/#3-a-centrifugal-pumps/=c701ja


Part number: 49635K41

It is 1/2 hp pump I should have bought 1 hp pump.

There is no way to prove that my pump does not pump 50 GPM.
I could inquire about leaking.
Now spec said that it will pump to thicknes of "Maximum viscosity is 50 centipoise (similar to SAE 10 oil)."
I think it does not leak when pumping water or CIP but it leaks with wort of 20 brix (while mashing).

[punatic]

Your pump is rated for 30 gpm at around 23 ft. (10 psi) of head.

Are you pushing beer through a filter with this pump?  It has a max head rating of 33 ft. (14.3 psi).  If you are pushing against a loaded up filter, at 14 psi it would essentially be dead-heading the pump, which could cause leaks.

160 F wort with a specific gravity of 1.083 is less viscous than 10 weight motor oil.

Talk to your McMaster's rep and see what he thinks.

[Will's Swill]

160 F wort with a specific gravity of 1.083 is less viscous than 10 weight motor oil.

Ya, way less.  160F wort at 20 Brix is only about 2 centipoise.

[Thirsty_Monk]

Thanks Will.

In meantime I bought another used milk pump.

[narvin]

I think it does not leak when pumping water or CIP but it leaks with wort of 20 brix (while mashing).

What is your mash tun like?  You don't want to restrict a centrifugal pump on the input side... are you getting enough flow?

Or maybe it's just a piece of crap.

[Thirsty_Monk]

I think it does not leak when pumping water or CIP but it leaks with wort of 20 brix (while mashing).

What is your mash tun like?  You don't want to restrict a centrifugal pump on the input side... are you getting enough flow?

Or maybe it's just a piece of crap.

That might me am issue too.
Pump is 1 1/2" In but my brewhouse has only 1" valves.

[Thirsty_Monk]

I think I got it.

You guys did not tell me to check the motor rotation.
I feel so stupid.

I bought a 1 hp electric motor for my mill.
Uppon arrival I discover that both motors have the same size of shaft and mounting bolts.
Mc master have the same pump head with lager motor. That made me thinking.

So I swapped the motor and wired it up. Plugged it into the kettle and it is water is moving.
Now I have an issue that my intake hose is collapsing.
So may be 1/2 motor was big enough but I am not swapping it back.

[punatic]

If you restrict the suction side of your pump you could cause it to cavitate and ruin your pump.

[Thirsty_Monk]

If you restrict the suction side of your pump you could cause it to cavitate and ruin your pump.

Yes I am aware of it.
If I restrict out flow hose does not collapse.
Also this was with 80F water and hose was still stiff.
I might end up with new thicker wall hose on in side.
When will spending end?

[denny]

When will spending end?

Man, I'm afraid I've got some bad news for you....

[SpanishCastleAle]

I just read this thread and the whole time I was thinking; "Did you check the rotation?"  Many centrifugal pumps will still pump in the 'forward' direction when spinning in the wrong direction, so that can throw you.

As far as the leaking; when tightening up that clamp around the pump housing, lightly tap around the clamp with a hammer/mallet as you tighten it.  That can sometimes help.  And of course, make sure the o-ring is seated correctly (I'm assuming it uses an o-ring there, I use similar pumps at work).  TBH, those clamp-types often just don't seal that well.