Can I remove the dredge pump from my keene dredge and run just the t-80 for sniping?

Ragnor

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Well The title says it all , mostly.

I'm also wondering if there are things I need to be careful about when taking the pump apart. I have allot of mechanic experience but I am still pretty scared of damaging the dredge pump before I ever get a chance to use it.

Not sure If I should just pull the T-80 and hook it to a different engine or pull the centrifical pump and use the dredge motor.

My idea is using the motor with the t-80 for surface supplied air for gold diving/sniping.
 

ORAUhunter

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Can I remove the dredge pump from my keene dredge and run just the t-80 for s...

If it was me I'd put the T-80 on another motor. I'm guessing your dredge motor is a 6.5 hp. You can probably run the T-80 alone on a much lighter 2.5 hp motor. Less weight and I hate messing with pumps and seals that don't need messing with.
 

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Ragnor

Ragnor

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I have a nearly brand new honda 2.5 on a nice cart I was thinking of. It came from a pressure washer a year old that cracked the plastic pistons over the winter. So it's basically a brand new motor on a cart. Except it has a weird square-ish slip yoke on the front of the crank. Anyone know a slick kit for converting that to a pulley?

I have to edit this: I just went out and looked and the motor has a splined crankshaft with a threaded hole in the center. Not a square one. I was thinking of a different motor.
 

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ssdsupply

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If you just take off the outer part of pump and remove impeller with half of seal you can then run the engine without destroying the seal.
 

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Ragnor

Ragnor

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2.5 hp briggs/Honda max and use a small pump for crevice blasting for max production. John

Honda engine I have turns out to be a 5hp, I was thinking it's was a 2.5 hp . So I have to ask, why 2.5 Max hp?
 

Jason in Enid

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Honda engine I have turns out to be a 5hp, I was thinking it's was a 2.5 hp . So I have to ask, why 2.5 Max hp?

Because you don't need the ponies to push a large volume of water and run the compressor. Running an engine twice the size is just wasting fuel, but if it's all you got then use it. It's like my pickup truck with a V8 engine. Gas economy sucks for driving around town, but I can't tow my trailer and toys with a prius. So I suffer around town and enjoy it when I need it. If you're never going to need all that power, sell it and buy a 2.5 If you just don't need it now, take the pump off and use it for the compressor.
 

winners58

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If you just take off the outer part of pump and remove impeller with half of seal you can then run the engine without destroying the seal.

This ^ ^ ^ ^ ^ :thumbsup:
spin off the impeller counter clockwise put the outer case back on. save's having to set anything up then tear it back down,
also protects the threads, just spin the impeller back on to dredge, good to go...
 

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Ragnor

Ragnor

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The rear housing seal won't be destroyed running it dry? I always understood this to be the problem with running a pump dry. Granted my total experience with dredging was the 8" hole I sucked in the yard before my horse trough went empty when testing my dry land nozzel.
 

winners58

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the seal does not touch the shaft the spring side presses against the ceramic disk on the back of the impeller.
Its always good to know how it all works, you'll eventually be replacing a seal one day, lets just say I now carry a spare.
.
wps2_1a.jpg
 

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Ragnor

Ragnor

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Somthing just for the sake of clarity. I pulled the honda out into the daylight today. I was on a fix'n binge. So anyway while I was getting the motor running I was watching the wierd 10 splined slip yoke that ran the pressure washer turning around. Lo and behold it had a set screw in it. Pulled that out and the yoke came off to reviel a short thick strait keyed shaft. I guess some how or another it had always stopped with the set screw facing down before. So I'm just a little less ignorant for my trouble. Should be allot easier to find a pulley now if I can't turn up a smaller motor. They put some really powerful motors on stuff these days. I got a honda mower with a busted pull rope off the side of the road for free. That stupid thing has a 6.5 horse on it. lol. Harbor frieght might sell the only 2.5hp motors left :laughing7:
 

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Ragnor

Ragnor

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Thank you for the information by the way. I had just assumed the rear seal was some kind of moden version of "packing" Like tesla used in his pumps. Good to know, good to know.
 

NeoTokyo

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Another thing about pulling the pump off and just running the T80, its pulley set is setup so that the T80 is at 1800rpms while the engine is at 3600rpms (Generally speaking).
That being said, you probably have a 3" engine pulley and a 6" compressor pulley or a 2.5"x5".
With that engine you don't need to be anywhere near those kind of rpms to have the power required to run the T80 (Which is around 1hp.)
You could run at 2100rpms and run a 3"x3.5" to get the 1800rpms that you need on that engine.

The reason why not to just run a 1:1 ratio and run the engine at 1800rpms is because the engine idles high as it is, the manual says 1800rpms +/-50rpms.
A little fuel makes a little more power and helps to smooth the engine out.
You can pick up a cheap digital rpm gauge that kart guys use to see what rpms you are running.

Make sure to have a couple pulleys, they are cheap at Ace Hardware (About 12-18 bux depending on the pulley) and buy a couple spare keys while you are there.


You can use a pulley RPM Calculator like this one to figure out what pulley you need to maintain the T80's optimal 1800rpms.

Pulley Calculator. RPM, Belt Length, Speed, Animated Diagrams
 

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Hoser John

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GOOGLE Thomas compressors and find the proper rpm from the website as EASY to burn them up with excessive rpm. Manual comes with new ones. Neo this forum thread(removal of a pump) has the info you pm'd me about with Reed removing the pumps also Russau posted the link to GoldDredger video on rebuilding t80s also on yet another post. John
 

NeoTokyo

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Thankyou John, I have seen Reeds video about the proline pump removal but the Gold King doesn't have the vanes exposes so I cant get ahold of it to brake it loose.
I don't know where I am suppose to use a leverage point on it.

Proper RPM for the T80 is 1800rpms, no higher than 2000rpms @ 40psi.
 

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