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DavidRamey
04-01-2013, 01:00 PM
I am thinking about getting a Keene mini 6" dredge next year.
It comes with a 1 13hp Honda engine and PHP500 pump or
2 6.5hp Honda engines and P180 pump or
2 6.5hp Honda engines and PHP500 pump.

Which configuration do you recommend and why?

IdahoHick
04-01-2013, 01:08 PM
I would like to think One engine one set of problems, One mouth to feed fuel to, If you are going bush you would only need two sets of spares for the things that could fail...Drawbacks...weight of one big engine.

DavidRamey
04-01-2013, 01:19 PM
I have a Keene mini 4" dredge with the Honda 6.5hp engine and P180 pump. The honda 6.5hp engine is very reliable and economical on fuel. I would already have spare parts on hand. So I am kind of leaning towards the 6" dredge with 2 Honda 6.5hp engines. If I got the 6" with the P180 pump that would require no additional spare parts because I would already have spare seal, hoses and foot valve. Would the PHP500 pump allow more production?

Steve Herschbach
04-01-2013, 02:00 PM
I can barely carry that big motor, I can carry a GX200 5.5HP (there is no 6.5HP) all day. I can use one of the 5.5HP pumps to run a 4" dredge or highbanker. At Moore Creek, we had 6", 4", and highbankers, all running same pumps and motors.

I am not aware of PHP500 being available on the GX200 5.5HP. Far as I know it is still P180. You can get the PHP500 on the 8.5HP GX270.

Production is limited by nozzle size and load capacity of sluice box, not pump size.

DavidRamey
04-01-2013, 02:33 PM
Thanks Steve. It sounds like I will go with the 2 Honda GX200 engines with P180 pumps. The PHP500 pump is listed in the new Keene catalog they mailed me. I was just wondering if there was any advantage in using the larger pump.

geowizard
04-01-2013, 04:22 PM
I bought the Keene 6218HM with Two 9HP Hondas driving P289 pumps rated at 350 GPM each. I run at a high idle. Honda is optimistic about HP rating and their HP is less than rated. Steve did a thread on this once as I recall.

- Geowizard

chickenminer
04-01-2013, 06:43 PM
David,
I've got a Precision 5" with the Honda 13HP engine. If you gotta pack the thing, like Steve said, it's a beast!
If I was to buy the 6" mini I'd go with the twin GX200's.

Brian Berkhahn
04-01-2013, 07:17 PM
This is an easy decision.. twin GX200 w/p180 pumps. Exactly what Steve said, you can use them for other things.. anything more then that is overkill and your just throwing your money away but I'll be happy to sell you more then you need if you want. The only real decision should be T80 or 263? T80 is fine for one person but a 263 is great for 2 people or IF you want to use an air hammer.

ManVSgold
04-02-2013, 12:09 PM
I can barely carry that big motor, I can carry a GX200 5.5HP (there is no 6.5HP) all day. I can use one of the 5.5HP pumps to run a 4" dredge or highbanker. At Moore Creek, we had 6", 4", and highbankers, all running same pumps and motors.

I am not aware of PHP500 being available on the GX200 5.5HP. Far as I know it is still P180. You can get the PHP500 on the 8.5HP GX270.

Production is limited by nozzle size and load capacity of sluice box, not pump size.


Im sooooooo confused.I see so much conflicting info on this.Clear me up steve on the GX200.There is no 6.5? What exactly do you mean by that?

http://i1218.photobucket.com/albums/dd417/ronpaul4pres/New/198592_605145656930_251712467_n_zpse48995db.jpg

http://i1218.photobucket.com/albums/dd417/ronpaul4pres/New/lrnrgadhqwtvvdk_zpsb0abe23a.jpg

http://i1218.photobucket.com/albums/dd417/ronpaul4pres/New/6085_zps3df3699c.jpg

ManVSgold
04-02-2013, 12:13 PM
I have 2 gx200's and some say they are 6.5's and some say they are 5.5's.They are on a dk nugget 6"dredge and I would really like to know how much hp I have.Mine do not say 6.5,they just say gx200 :confused:

Steve Herschbach
04-02-2013, 12:16 PM
Oh, you are thinking that because that motor has a 6.5 on the side it means it is a 6.5HP. You big silly!

The short answer is it is a GX200 - that part is true. Details below.

Confusion over Honda Horsepower

http://www.akmining.com/forums/showthread.php/1020-Confusion-over-Honda-Horsepower?p=6540&viewfull=1#post6540

ManVSgold
04-02-2013, 12:24 PM
thank you soooo much steve.I been looking for this info for a long time and the honda site does nothing to help.So i have 2 5,5's. You should make that post you linked me to super sticky. Such great info.

ManVSgold
04-02-2013, 12:31 PM
My next question is why would Keene market them as a 6.5 hp when they know they're not?http://i1218.photobucket.com/albums/dd417/ronpaul4pres/New/keene65hp_zpsfb0e5a3d.jpg

Steve Herschbach
04-02-2013, 12:46 PM
Ha, ha, ha, ha, ha! Because they are too busy to update their website and do not realize that it might maybe get them in a wringer with somebody at some point. I gave up trying to get it changed. It causes lots of problems when people think we are selling units with less horsepower.

GX200s are what they are - a GX200 has always put out X. It is all about how you define X. Technically 5.5 and 6.5 are both accurate, just measured different ways. Gross HP vs net HP. In the outboard world in Alaska you should see the debate that arose over horsepower measured at the powerhead versus horsepower measured at the prop, and then at the jet nozzle.

All of which is why you in a parts department stick to model and serial number. Always know your model, type and serial number!!! There are many tiny variations of the GX200 based on type and serial number, for stuff as simple as the type of gas cap used or as complex as the type of driveshaft mounting.

DavidRamey
04-02-2013, 12:58 PM
There are two kinds of SAE horse power ratings. The first type (old type) is just the engine without any load or accessories (not as installed) on a dynamometer (a machine that figures HP and torque) and is generally referred to as gross hp. The second type (new type) is the engine with accessories as installed on a dyno and is generally referred to as net hp. When the GX200 was rated at 6.5 hp (gross hp), it was rated that way because it had no load or accessories installed on the engine. Now the GX200 is rated 5.5 hp (net hp) because it is put on the dyno as the engine is installed with accessories. Most engine manufacturers stopped using hp rating because they have no idea what accessories would be installed on the engine and different accessories installed could result in different hp ratings. It is possible that Keene is getting 6.5 hp with their P180 pump installed. I, myself, doubt that Keene is testing the GX200 w/P180 pump on a dyno to get the 6.5 hp rating; but rather is just printing what they always printed in their catalog and never corrected the hp rating in their catalog.

ManVSgold
04-02-2013, 01:26 PM
I see now.Thank you both for the great explanations. Leaves me with the thought, I kinda got screwed a little bit when i bought my dredge from keene.I thought I was getting a 6.5 hp motor (when measured by the most common US standard) but that seems not to be the case.Its seems a little misleading but o well I guess.

On a side note,the 3" keene was a champ and the motor was great.

But that gets me thinking the 13 hp is a possible better purchase, since you get those extra 2 HP.I guess if your pack'en it, two 5.5's would be better and if your back'en it, one 13HP would be better.

Steve Herschbach
04-02-2013, 01:34 PM
There is no 13HP. It is an 11.7HP - got to go apples to apples.

You can go with a pair of 6.5HP or a single 13HP

OR

you can go a pair of 5.5HP or an 11.7HP.

Take your pick but it is same motors in either scenario. Pair of GX200 vs single GX390.

AKdredger
04-02-2013, 01:35 PM
Go with the 2 smaller motors. Its the best bet, been using that dredge for nearly 15 years. No problems, its been frozen, sunk, dragged behind wheelers, snowmachines and still is making me gold. I have 16hps on my 8" and can barely lift them to my tailgate of my truck much less carrying them anywhere on the river bank. And trust me I am a more horse power is better type of guy, but you can only lift so much weight for so far.

ManVSgold
04-02-2013, 02:27 PM
There is no 13HP. It is an 11.7HP - got to go apples to apples.

You can go with a pair of 6.5HP or a single 13HP

OR

you can go a pair of 5.5HP or an 11.7HP.

Take your pick but it is same motors in either scenario. Pair of GX200 vs single GX390.

I understand now Steve.Thank you!

DavidRamey
04-02-2013, 04:30 PM
the torque is more important than the hp. the horsepower is at 3600 rpm (max throttle). the maximum torque is at 2500 rpm (about the speed you will be running the dredge).

geowizard
04-02-2013, 07:04 PM
Accessories are "muffler" and air cleaner"...

from Honda:

"The SAE J1349 standard measures net horsepower with the manufacturer’s production muffler and air cleaner in place. Net horsepower more closely correlates with the power the operator will experience when using a Honda engine powered product. The power rating of the engines indicated in this document measures the net power output at 3600 rpm (7000 rpm for model GXH50, GXV50, GX25 and GX35) and net torque at 2500 rpm, as tested on a production engine. Mass production engines may vary from this value. Actual power output for the engine installed in the final machine will vary depending on numerous factors, including the operation speed of the engine in application, environmental conditions, maintenance and other variables. "

Note also, variability in "production" will affect "your" performance!

Finally, Centrifugal pumps pump more "volume" at higher RPM. So, stick with RPM. :)

I bought the two 9 HP (net 8.5 HP) Hondas and they run larger pumps at lower RPM with no loss of performance. If you start with the 6.5 HP (net 5.5 HP) and then run at 2500 RPM, you can expect combined HP of around 4 HP (2 HP each). Not much work will get done with that amount of power. The reasons for de-rating power are all of the factors that reduce engine performance; tuning, fuel, ambient temperature, humidity and air density.

- Geowizard

DavidRamey
04-02-2013, 07:43 PM
But you don't want the volume of the pump to be so high that you blow the gold out of the end of the sluice. Most dredgers I know set the throttle between 1/2 and 3/4 throttle and that is where the highest torque is created.

Steve Herschbach
04-02-2013, 08:51 PM
Actually the Honda horsepower rating difference has nothing to do with any of the above. It has to do with a consortium of motor manufacturers creating their own standard to inflate numbers relative the competition and getting caught.

http://www.bigclassaction.com/settlement/lawnmower-class-action.php

http://www.jsonline.com/business/85489322.html?ipad=y

http://www.scribd.com/doc/63007974/Class-Action-Lawsuit-Lawn-Mower-Horsepower

I remember way back when Honda said the GX200 was 5.5HP in the owners manual. Then one day they went up a horsepower. I figured they bored it out or recarbed or otherwise got more power out of the engine. No, they simply adopted a new way of rating the motor. Most of the big names in the industry were in on it. None admitted guilt in the class action suit, they just paid out $65 million to settle. And all the manuals and specs magically went back down to where they were before.

And now you know the rest of the story.

Brian Berkhahn
04-02-2013, 09:45 PM
Go with the 2 smaller motors. Its the best bet, been using that dredge for nearly 15 years. No problems, its been frozen, sunk, dragged behind wheelers, snowmachines and still is making me gold. I have 16hps on my 8" and can barely lift them to my tailgate of my truck much less carrying them anywhere on the river bank. And trust me I am a more horse power is better type of guy, but you can only lift so much weight for so far.

Once again.. YUP

Brian Berkhahn
04-02-2013, 09:52 PM
But you don't want the volume of the pump to be so high that you blow the gold out of the end of the sluice. Most dredgers I know set the throttle between 1/2 and 3/4 throttle and that is where the highest torque is created.

Not true, we run our dredges 1/2 to 3/4 throttle not because it's where the highest torque is created but because it's the proper water flow.

carter
04-03-2013, 09:04 AM
I know altitude plays a big part in power loss on smowmachines but we are talking 100hp engines. I cant remember if it is like 10% loss every 1000ft above sea level.? I think alot of the engines are jetted for 0-3000ft. My claims are close yo the 3000 level and maybe a few % loss is a big deal on my 4hp honda?
As for the single/double engines,
I picked the single on my 6" last yr. on the basis of only dealing with one hole in the creek for my pump ft. valve (my claims are on a creek that is very shallow) and simplicity of just one engine. The pump on it is not the new 500 with the hose outlet port at a angle like on the keene site. I called keene and talked to pat keene and they put the 350 on it cause they found out the new 500 wasnt getting the volume that the older style. Dont know if this has changed this yr. though

Carter

Steve Herschbach
04-03-2013, 11:02 AM
Working at high altitudes, working in very deep water, or adding lots of extra suction hose are all reasons to consider larger motors. Also, in long term operations a large motor running at lower RPMs is more fuel efficient and will last longer than a motor running at full throttle.

geowizard
04-05-2013, 09:51 AM
My sentiments exactly. YUP! :)

- Geowizard