I just bought a trash pump without the gas engine.
http://tinyurl.com/d3qj5f

What RPM do I spin it at?

FWIW, I hate small gas engines. Nothing but trouble. I'll use a 3 phase
motor for this job.

Karl

On Fri, 03 Apr 2009 17:43:36 -0500, Karl Townsend wrote:

I just bought a trash pump without the gas engine.
http://tinyurl.com/d3qj5f

What RPM do I spin it at?

FWIW, I hate small gas engines. Nothing but trouble. I'll use a 3 phase
motor for this job.

Karl

At a guess I'd say 1800 ought to work. Gen sets with Vibration &
Stratton engines seem to spin at that rate.

--
http://www.wescottdesign.com

In article s.com,
says...
I just bought a trash pump without the gas engine.
http://tinyurl.com/d3qj5f

What RPM do I spin it at?

FWIW, I hate small gas engines. Nothing but trouble. I'll use a 3 phase
motor for this job.


The standard governed speed for 4 cycle engine like lawn mowers is 3600.


--
Dennis

Standard small engine (single cylinder, 4 cycle, 3 to 14 hp) rpm is
3600, some later engines run a few hundred RPM faster.


http://www.northerntool.com/webapp/w...70_14323_14323

Most of the pumps I found were rated at 3450 to 3600 RPM for full
output. Note that you can get trash pumps, semi-trash pumps, clear water
pumps, and high pressure pumps.

Yours appears to be a semi trash variety. This is good for some soft
solids like an occasional leaf or bird dropping, high volume, lower
pressure.


Karl Townsend wrote:
I just bought a trash pump without the gas engine.
http://tinyurl.com/d3qj5f

What RPM do I spin it at?

FWIW, I hate small gas engines. Nothing but trouble. I'll use a 3 phase
motor for this job.

Karl

In article s.com,
Karl Townsend wrote:
:I just bought a trash pump without the gas engine.
:http://tinyurl.com/d3qj5f
:
:What RPM do I spin it at?
:
:FWIW, I hate small gas engines. Nothing but trouble. I'll use a 3 phase
:motor for this job.

http://www.google.com/search?q=power...pm&btnG=Search

Looks like a 3600 RPM electric motor should be a good match.

--
Bob Nichols AT comcast.net I am "RNichols42"

"RoyJ" wrote in message
m...
Standard small engine (single cylinder, 4 cycle, 3 to 14 hp) rpm is 3600,
some later engines run a few hundred RPM faster.

The 4 cyl. Continental on my SA 200 welder runs at 1450 rpm.

Steve

"Karl Townsend" wrote in message
anews.com...
I just bought a trash pump without the gas engine.
http://tinyurl.com/d3qj5f

What RPM do I spin it at?

FWIW, I hate small gas engines. Nothing but trouble. I'll use a 3 phase
motor for this job.

Karl



How about a VFD?

For long life you want most common engines to run in the 1400rpm to 2000
rpm range (depending on size). Ditto for noise, faster = noisier. 60HZ
alternators need to be locked at 1200rpm, 1800 rpm, or 3600 rpm for 6
pole, 4 pole, and 2 pole alternator heads. Yours is a DC unit, they can
build the windings to produce optimal output at whatever the engine
wants. 1400 rpm in a 4 cylinder flathead is a long life setup.


SteveB wrote:
"RoyJ" wrote in message
m...
Standard small engine (single cylinder, 4 cycle, 3 to 14 hp) rpm is 3600,
some later engines run a few hundred RPM faster.

The 4 cyl. Continental on my SA 200 welder runs at 1450 rpm.

Steve

On Fri, 03 Apr 2009 17:59:43 -0500, Tim Wescott
wrote:

On Fri, 03 Apr 2009 17:43:36 -0500, Karl Townsend wrote:

I just bought a trash pump without the gas engine.
http://tinyurl.com/d3qj5f

What RPM do I spin it at?

FWIW, I hate small gas engines. Nothing but trouble. I'll use a 3 phase
motor for this job.

Karl

At a guess I'd say 1800 ought to work. Gen sets with Vibration &
Stratton engines seem to spin at that rate.


99.99% of 4 stroke small gas engines are governed and rated at 3600
RPM

On Fri, 3 Apr 2009 19:42:00 -0600, "SteveB"
wrote:


"RoyJ" wrote in message
om...
Standard small engine (single cylinder, 4 cycle, 3 to 14 hp) rpm is 3600,
some later engines run a few hundred RPM faster.

The 4 cyl. Continental on my SA 200 welder runs at 1450 rpm.

Steve

But that is not a "small engine"

wrote in message
...
On Fri, 3 Apr 2009 19:42:00 -0600, "SteveB"
wrote:


"RoyJ" wrote in message
news:HOCdndtvvOKtA0vUnZ2dnUVZ_rmdnZ2d@earthlink. com...
Standard small engine (single cylinder, 4 cycle, 3 to 14 hp) rpm is
3600,
some later engines run a few hundred RPM faster.

The 4 cyl. Continental on my SA 200 welder runs at 1450 rpm.

Steve

But that is not a "small engine"

Sorry, but previous posters included 4 cyl engines.

On Apr 3, 3:43*pm, "Karl Townsend"
wrote:
I just bought a trash pump without the gas engine.http://tinyurl.com/d3qj5f

What RPM do I spin it at?

FWIW, I hate small gas engines. Nothing but trouble. I'll use a 3 phase
motor for this job.

Karl

_________________________________________________


3000 RPM .

Need to start on Propnae . Exh is routed around to heat liquid fuel
and
to "regenerate" heat into the intake .
Then switch to liquid , turn off propane .


Japan cant sell machinery in U.S. ,
Jap' makes motors in China , China trademark . missing the Jap name

Price is highly subsidized .
13HP motor has a balance shaft and retards camshaft to lower
cranking PSI , for easy starting .

How about a VFD?

A 3600 RPM 5 hp. may be hard to find. I'll start shopping eBay for a 5hp.
VFD. Didn't really want to put this much $ into this job though.

Karl

DAGS

Powerhorse+pump+RPM

http://www.google.com/search?hl=en&q...ay&btnG=Search

3400-5500 RPM depending upon size and engine used, based upon a quick glance
at the search results.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"Karl Townsend" wrote in message
anews.com...
I just bought a trash pump without the gas engine.
http://tinyurl.com/d3qj5f

What RPM do I spin it at?

FWIW, I hate small gas engines. Nothing but trouble. I'll use a 3 phase
motor for this job.

Karl

"Karl Townsend" wrote in message
anews.com...
How about a VFD?

A 3600 RPM 5 hp. may be hard to find. I'll start shopping eBay for a 5hp.
VFD. Didn't really want to put this much $ into this job though.

Karl




A 3450 RPM should be easy to find, and work well enough. The 150 drop in RPM
will not affect the GPM enough to notice. Plus you not need the VFD.
Greg

On Fri, 3 Apr 2009 17:43:36 -0500, "Karl Townsend"
wrote:

I just bought a trash pump without the gas engine.
http://tinyurl.com/d3qj5f

What RPM do I spin it at?

FWIW, I hate small gas engines. Nothing but trouble. I'll use a 3 phase
motor for this job.

If you want to use an electric motor you can go a bit smaller - If
it calls for 5.5 HP gas engine, you can probably drop to a real 3 HP
electric motor - a 5 HP would spin it without breaking a sweat.

For some reason small gas engines are rated at gross HP, and when you
subtract the power used to run the cooling fan...

And find out the optimum speed for the pump head - probably 2,400
RPM to 3,600 RPM range common for gas engines.

This style pump head is meant to direct-mount onto a certain tapered
crankshaft tail normally found on gasoline engines - which you are NOT
going to find on regular electric motors. The pump impeller has the
female of the tapered shaft with the lockbolt, and the tolerances when
it's all bolted together is critical.

Pool pumps and stationary pressure pumps are built to bolt to a
standard C-face pump duty motor with straight keyway shaft, not these.
If you search, you can probably find a semi-trash style pump made for
an electric drive - just like you can find prerssure washer pumps
built both ways.

If you really want to go electric with that particular pump head,
you need a pedestal adapter for the pump. It has the proper tapered
shaft with center bolt, a pedestal in the middle with two shaft
support bearings and and bolting face at one end to mount the pump, a
mounting foot built into the casting, and the other shaft end has a
straight shaft with keyway to mount a standard drive pulley or a
Lovejoy Coupling.

Thern you vary the pulley ratios to drop the speed a bit from the
3,450 RPM of the electric motor to the ~2,400 RPM that the pump head
really wants.

-- Bruce --

"Greg O" wrote in message
...
"Karl Townsend" wrote in message
anews.com...
How about a VFD?

A 3600 RPM 5 hp. may be hard to find. I'll start shopping eBay for a 5hp.
VFD. Didn't really want to put this much $ into this job though.

Karl




A 3450 RPM should be easy to find, and work well enough. The 150 drop in
RPM will not affect the GPM enough to notice. Plus you not need the VFD.
Greg

Here is one for example, EBay #120391225187
Greg

"Karl Townsend" wrote in message
anews.com...
I just bought a trash pump without the gas engine.
http://tinyurl.com/d3qj5f

What RPM do I spin it at?

FWIW, I hate small gas engines. Nothing but trouble. I'll use a 3 phase
motor for this job.

Karl



Karl, I have repaired a ton of small engine powered pumps over the years,
3-8 HP, and I have ONLY seen engines running at 3600 RPM. No other RPM's,
just 3600.
Look for a electric motor running about 3450 it will work fine running
direct drive. No belts, no VFD needed. You will more than likely need to
build a mount and shaft setup to mimic the gas engine that would normally be
supplied with that pump.
Greg

For some reason small gas engines are rated at gross HP, and when you
subtract the power used to run the cooling fan...

Not really, we have run these small engines on a legitimate dyno at one
of the major lawnmower mfg facilities. (They paint their stuff red) The
engines tend to put out less than the engine mfg lists: something like
95% of the nameplate number down to not much over 50%

But the real reason you need a larger gas engine than electric is that
the gas engine has no additional torque capability, an electric motor
does. A 20% overload for 1 second will kill a gas engine cold. Same
overload on an electric motor will cause a surge in input power, not
much else.


And find out the optimum speed for the pump head - probably 2,400
RPM to 3,600 RPM range common for gas engines.

I'd expect ANY pump in this class to be set up for 3600 rpm. It's the
standard speed for both gas and electric motors.

This style pump head is meant to direct-mount onto a certain tapered
crankshaft tail normally found on gasoline engines - which you are NOT
going to find on regular electric motors. The pump impeller has the
female of the tapered shaft with the lockbolt, and the tolerances when
it's all bolted together is critical.

The OP listing clearly states "3/4 inch straight shaft with keyway"

Pool pumps and stationary pressure pumps are built to bolt to a
standard C-face pump duty motor with straight keyway shaft, not these.
If you search, you can probably find a semi-trash style pump made for
an electric drive - just like you can find prerssure washer pumps
built both ways.

If you really want to go electric with that particular pump head,
you need a pedestal adapter for the pump.
A lot of work with no benefit.

It has the proper tapered
shaft with center bolt, a pedestal in the middle with two shaft
support bearings and and bolting face at one end to mount the pump, a
mounting foot built into the casting, and the other shaft end has a
straight shaft with keyway to mount a standard drive pulley or a
Lovejoy Coupling.

Thern you vary the pulley ratios to drop the speed a bit from the
3,450 RPM of the electric motor to the ~2,400 RPM that the pump head
really wants.

-- Bruce --

On Sat, 04 Apr 2009 21:02:46 -0500, RoyJ
wrote:
Bruce wrote:

This style pump head is meant to direct-mount onto a certain tapered
crankshaft tail normally found on gasoline engines - which you are NOT
going to find on regular electric motors. The pump impeller has the
female of the tapered shaft with the lockbolt, and the tolerances when
it's all bolted together is critical.

The OP listing clearly states "3/4 inch straight shaft with keyway"

O Rly?

I read the eBay listing referenced as a tapered shaft with an end
hole for a lock bolt. Sure you looked at the right page? They :do:
come both ways.

-- Bruce --

--
PoorUB
'05 Ultra Classic
"Bruce L. Bergman" wrote in message
...
On Sat, 04 Apr 2009 21:02:46 -0500, RoyJ
wrote:
Bruce wrote:

This style pump head is meant to direct-mount onto a certain tapered
crankshaft tail normally found on gasoline engines - which you are NOT
going to find on regular electric motors. The pump impeller has the
female of the tapered shaft with the lockbolt, and the tolerances when
it's all bolted together is critical.

The OP listing clearly states "3/4 inch straight shaft with keyway"

O Rly?

I read the eBay listing referenced as a tapered shaft with an end
hole for a lock bolt. Sure you looked at the right page? They :do:
come both ways.

-- Bruce --

O Rly?
Stolen off the EBay page, Are you confusing tapped with tapered? Bifocals
not working for you?
I have never seen a 3-8 HP gas powered pump with a tapered shaft, and I have
worked on many of them over the years. Straight shaft, threaded, or keyed is
the norm. Generator engines of that size are typically tapered. Keep in mind
on most pumps you need to be able to shim the impeller to keep tight
clearances so the pump will work efficiently.
Greg

Powerhorse pump requires 5.5 HP engine with 2 7/16in.L, 3/4in. straight
keyed shaft, 5/16in.-24 tapped hole and 3 5/8in. bolt circle.


a.. 1 1/8in. soft solids capacity
b.. Pump delivers 11,520 GPH with 82ft. max. head
c.. Silicon carbide seals
d.. Durable cast iron impeller and volute
e.. 3in. suction/discharge ports

This link
http://tinyurl.com/d3qj5f

has this text

Powerhorse pump requires 5.5 HP engine with 2 7/16in.L, 3/4in. straight
keyed shaft, 5/16in.-24 tapped hole and 3 5/8in. bolt circle.

Very similar to the Pacer Pumps I use for high volume applications:
http://www.dultmeier.com/pdfs/prSser2.pdf
Note the straight shafts on all the different mounting and drive methods
including electric motor drive.

I am quite familiar with pool/spa pumps, have two complete 1-1/2 hp
pump/motors and two spare motors in the stock room. These have straight
shafts with left handed nut to hold the impeller on.

Bruce L. Bergman wrote:
On Sat, 04 Apr 2009 21:02:46 -0500, RoyJ
wrote:
Bruce wrote:

This style pump head is meant to direct-mount onto a certain tapered
crankshaft tail normally found on gasoline engines - which you are NOT
going to find on regular electric motors. The pump impeller has the
female of the tapered shaft with the lockbolt, and the tolerances when
it's all bolted together is critical.
The OP listing clearly states "3/4 inch straight shaft with keyway"

O Rly?

I read the eBay listing referenced as a tapered shaft with an end
hole for a lock bolt. Sure you looked at the right page? They :do:
come both ways.

-- Bruce --

To qualify engines, they take a couple sample engines out of the box
(just like they would on the assembly line), put it on the dyno, fire it
up, adjust the dyno to the max load it will handle for a 6 hour (full
load) break in period. Then they run a full torque vs rpm curve for the
engine. Simple math gets you the max hp.

The dyno guys tell me that the B&S Intek 10 HP engine we brought in ran
out at 9.4 hp on a "10 HP engine", one of the best that they had seen.
My students were fairly shocked that it was that low. The dyno guys said
they had seen similar tests running at something like 55%.

Any of the standard things would improve the numbers: bigger jets is
probably the first thing on the list since these engines are designed
for minimum fuel consumption. The engines we were playing with had
fixed jets, no replacement jets available from the mfg. Pretty lean.
These engines were used for class racing, no mods allowed. We figured
that balancing, slippery oil, and larger jets would have pushed it to an
easy 11 hp. Tuned exhaust rather than stock muffler would add another
couple ponys.

We didn't try any of the 84 to 85 octane gas we get in Colorado, we
figure that might have gained a solid 10% right there. The lower octane
has slightly more fuel value per pound plus it doesn't have any alcohol
to lower the fuel value.

Jim Wilkins wrote:
On Apr 4, 10:02 pm, RoyJ wrote:
...
Not really, we have run these small engines on a legitimate dyno at one
of the major lawnmower mfg facilities. (They paint their stuff red) The
engines tend to put out less than the engine mfg lists: something like
95% of the nameplate number down to not much over 50%
...

Do you know why? Compression, carburation, ignition?

On Mon, 06 Apr 2009 17:20:40 -0500, RoyJ
wrote:

To qualify engines, they take a couple sample engines out of the box
(just like they would on the assembly line), put it on the dyno, fire it
up, adjust the dyno to the max load it will handle for a 6 hour (full
load) break in period. Then they run a full torque vs rpm curve for the
engine. Simple math gets you the max hp.

Needs to be corrected for "standard atmosphere" which is 70F at sea
level. At 70F and sea level that 9.4HP "10HP" engine would quite
likely excede its rated power.

The dyno guys tell me that the B&S Intek 10 HP engine we brought in ran
out at 9.4 hp on a "10 HP engine", one of the best that they had seen.
My students were fairly shocked that it was that low. The dyno guys said
they had seen similar tests running at something like 55%.

Any of the standard things would improve the numbers: bigger jets is
probably the first thing on the list since these engines are designed
for minimum fuel consumption. The engines we were playing with had
fixed jets, no replacement jets available from the mfg. Pretty lean.
These engines were used for class racing, no mods allowed. We figured
that balancing, slippery oil, and larger jets would have pushed it to an
easy 11 hp. Tuned exhaust rather than stock muffler would add another
couple ponys.

We didn't try any of the 84 to 85 octane gas we get in Colorado, we
figure that might have gained a solid 10% right there. The lower octane
has slightly more fuel value per pound plus it doesn't have any alcohol
to lower the fuel value.

Actually, premium gas goes not NECESSARILY have lower power density -
and up here if you want to guarantee no Ethanol you buy Shell PREMIUM.

MOST fuel vendors in Canada lace the low octane stuff with up to 10%
Ethanol. Mixed with 0% premium, you get 5% mid-grade.

MOST small OHV engines actually prefer high-test unleaded fuel,
possibly for that reason.

Most 2 stroke (like snowmobile) engines also prefer premium.
Jim Wilkins wrote:
On Apr 4, 10:02 pm, RoyJ wrote:
...
Not really, we have run these small engines on a legitimate dyno at one
of the major lawnmower mfg facilities. (They paint their stuff red) The
engines tend to put out less than the engine mfg lists: something like
95% of the nameplate number down to not much over 50%
...

Do you know why? Compression, carburation, ignition?

wrote:

Needs to be corrected for "standard atmosphere" which is 70F at sea
level. At 70F and sea level that 9.4HP "10HP" engine would quite
likely excede its rated power.

Doubt it. The test cell is room temp, elevation is 835 feet.


We didn't try any of the 84 to 85 octane gas we get in Colorado, we
figure that might have gained a solid 10% right there. The lower octane
has slightly more fuel value per pound plus it doesn't have any alcohol
to lower the fuel value.

Actually, premium gas goes not NECESSARILY have lower power density -
and up here if you want to guarantee no Ethanol you buy Shell PREMIUM.

MOST fuel vendors in Canada lace the low octane stuff with up to 10%
Ethanol. Mixed with 0% premium, you get 5% mid-grade.

Not here, many states mandate 10% ethyl alcohol. The Colorado fuel
mentioned is only sold at altitudes above 4000 feet, the thin air allows
the lower octane in a carburated engine. Doesn't fool a good computer
controlled engine with O2 sensors, hence the car mfg recommendations to
not use the stuff. But it does improve the power output in low
compression, lean jetted small engines.


MOST small OHV engines actually prefer high-test unleaded fuel,
possibly for that reason.

But the fuel BTU density is such that lower octane fuels have more BTU's
per volume, hence make a richer air:fuel mix. The small engines we are
talking about have compression ratios around 7.5:1 or 8:1, more than low
enough to handle the low octane fuel.


Most 2 stroke (like snowmobile) engines also prefer premium.

Most snowmobile engines are much higher performance than the typical one
lunger 4 cycle lawn or small industrial engine, like or need the high
octane.


Jim Wilkins wrote:
On Apr 4, 10:02 pm, RoyJ wrote:
...
Not really, we have run these small engines on a legitimate dyno at one
of the major lawnmower mfg facilities. (They paint their stuff red) The
engines tend to put out less than the engine mfg lists: something like
95% of the nameplate number down to not much over 50%
...
Do you know why? Compression, carburation, ignition?

On Apr 4, 1:27*am, "SteveB" wrote:
wrote in message

...

On Fri, 3 Apr 2009 19:42:00 -0600, "SteveB"
wrote:

"RoyJ" wrote in message
news:HOCdndtvvOKtA0vUnZ2dnUVZ_rmdnZ2d@earthlink. com...
Standard small engine (single cylinder, 4 cycle, 3 to 14 hp) rpm is
3600,
some later engines run a few hundred RPM faster.

The 4 cyl. Continental on my SA 200 welder runs at 1450 rpm.

Steve

But that is not a "small engine"

Sorry, but previous posters included 4 cyl engines.

I think they were refering to 4 cycle engines, to differentiate them
from two cycle engines like you'd find in chainsaws and string
trimmers...
--Glenn Lyford