Pump/motor size for 4" dredge??

tridge800

tridge800

Jr. Member
Sep 4, 2012
89
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Jamestown nc
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Garrett at gold
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All Treasure Hunting
First, you better make sure you know the thread dimensions of your pump. There are lot's of output shaft differences.

As for motor strength, AT LEAST 5 horse. If you have hookah air pump, make sure you have at least 6 horse.

For the pump, you need a 2.5 x 2 inch HP pump, something along the lines of the Keene P180. There are other manufacturers of similar pumps but I don't know their models.

If this is for a dredge, stay away from the trash or semi-trash pumps. They can move volume but don't have the pressure and you need both to work effectively.
 

Hey thanks Jason..will def get pump first then so I know what to look for in motor shaft size.As far as hookah,wont need that just yet as im in very shallow creeks. I saw that keener uses the p180 on their 4" but its a smaller box so I wasn't sure if it would be enough for the box I have.And as far as hoses do u know of any good places.From what u've found Armadillo mining looks to be the best prices I've seen so far.Ill obviously need 4" suction,but what other size hoses will I need and what length?? Thanks!!
 

Oh,forgot just for info sake i will be running suction nozzle..
 

Look in your area phone directory for industrial hose suppliers. Call them and ask if they carry Kana-flex 4" clear PVC suction hose. If so, you can find it MUCH cheaper than buying it online and paying a huge shipping charge.

Don't discount the hookah on shallow water! It is so much easier to lay, face down in the water, and really see the cobbles and avoid the ones that will cause a plug-up. Blind dredging sucks because you will spend as much time clearing plugs as actually dredging.
 

What ever you do on your pump make sure you match it with ther jet!

I learned this the hard way after I read a tread from Reed the fella who does all the dredge building vidieos
He had suggested putting a proline pump on one of the newer keene boxes .at the end of the day the keene p180 moved much more water thru the box
I'm sure the proline pump would have done fine if I had used there jet but i didn't see much since in it as the factory pump already would over flow the box

On hose check out 1st choice industral the shipping charges still work out better or they did for me
I use kanaflex 155 I don't use the standard suction hose it's much heavier and stiffer also the 155 is what most manufacturers use like keene
It what you will gti if you order keene hose .

Another thought on your engine dredge builders warehouse offers a pump to fit on a keyed shaft allowing you to use what ever eng you would like
The Honda clones run about 150 and they run as well but use there jet if you go that way ,

Most of the 4" dredges run a 16" box so you pretty much have your choices of who's pump to run
 

On the shipping note I bought 100' of 6" hose kanaflex155 gy and it ran 150 to ship it the hose ran 9.14 per foot where keene wianted 22 a ft plus shipping

The lenth would depend on how far you Wana work from your machine no more than 20 or you will start to lose suction.
The closer you are the more suction you will have.
 

G1sammons said:
What ever you do on your pump make sure you match it with ther jet!

I learned this the hard way after I read a tread from Reed the fella who does all the dredge building vidieos
He had suggested putting a proline pump on one of the newer keene boxes .at the end of the day the keene p180 moved much more water thru the box
I'm sure the proline pump would have done fine if I had used there jet but i didn't see much since in it as the factory pump already would over flow the box

The Proline HP400 3" x 2" adds 10% more power over the Keene P180 2½" x 2" when they are set up exactly the same. The difference in the manufactured jets are 1/8" id and not an issue. I suggested the Proline HP400 over the Keene P180 because it's 400gpm vs 350gpm unless you're running a Gast compressor which will draw more hp and cause them to run closer. Just the facts, this is how it is and how it has been since the HP400 came out. If you learned the hard way then you must have learned that you needed a bigger pump and more HP...
Click to expand...
 


It was a new dredge 6.5 hp motor when I changed the pump the the proline hp 400 pump I lost about 1/3 rd of the volume flowing out of the box.
Nothin els was changed !!!!
After the fact. I did some studying on eductors and found that the volume of the pump is not as important as the pressure that the pumps put out
As long as the pump has enough flow to be capable with the jet or eductor the pressure is what does the trick.
I wasn't knocking on you in anyway Reed your knowledge and videos have alway been a great help!!!!!
And would like to say thanks for all of the help you have provided us with thru the years !!!!
I know it's time consuming to make and post these vids for us and not many folks take the time anymore!!!!

It's a possibility I got a bad pump .i have couple of friends that have proline dredges and both of there units will flow much more than they need
I assumed,it was the difference in pressure capabilities of the 2 pumps and figured that there jets,were,larger allowing more water thru
I put my p180 back on and all was fine
Also the comp was a t80
Gary
 

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For my needs I'd go for a 6.5 briggs with a P-180(I have 3) and rock on. When dealing with microfine gold that suction nozzle will increase your retention BUT if your blastn' into a old school crash syle header box you just lost your edge in the recovery field. A good old over/under to scalp them fines has proven history for over 35 years now since our PESCO introduction and now industry standard for fines retention. There is also a keene SEMI CRASH with a smaller than normal flare that can be manupulated to do both-crashsmash for extreme high clay contents by cranking engine up or slow'r down and nice flar intorduction of rocks then also. John
 

Unless you tape or gouge the aluminum at the infeed it will suck air in where the 3" tube mounts on to the pump. This is a problem with all of them and this is where you were getting your pressure loss. You can't see or hear the air getting in but you can see the air bubbles going down the sluice box. It is a big pressure loss and to fix this because it is just aluminum, we put one wrap of duct tape around it before putting the hose on any Proline pump. The one wrap lasts most of the season even if you are pulling it apart and putting it back together every day.

Also Proline has a 1" jet outlet if I am remembering right where the Keene has ¾ to 7/8. The Keene is smaller and you get better pressure with the larger jet from my experience.
 

Reed Lukens said:
Unless you tape or gouge the aluminum at the infeed it will suck air in where the 3" tube mounts on to the pump. This is a problem with all of them and this is where you were getting your pressure loss. You can't see or hear the air getting in but you can see the air bubbles going down the sluice box. It is a big pressure loss and to fix this because it is just aluminum, we put one wrap of duct tape around it before putting the hose on any Proline pump. The one wrap lasts most of the season even if you are pulling it apart and putting it back together every day.

Also Proline has a 1" jet outlet if I am remembering right where the Keene has ¾ to 7/8. The Keene is smaller and you get better pressure with the larger jet from my experience.
Click to expand...

On the 1" are you referring to hose out let? Or the jet I'd on the pressure input on the jet log?
 

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