OT Hydraulic Pump Ideas Needed

I have a large hydraulic pump that I took off an old farm truck that had a dump bed. It had two hydralic cylinders that both were two stage cylinders. I was wondering how fast this pump may need to turn? I don't have any info on the pump. I have a Kohler 16hp V-twin cylinder engine that I want to hook the pump too. Just wondering if I need to hook it direct drive or chain drive with sprocket reduction? One thing nice is the pump has a dump valve on it this was actually used to lower the bed of the truck. So it will be able to idle without any load on the engine. I will be putting a seperate directional valve in the circuit to direct the flow of oil under pressure where I want it. I plan to put some quick disconnects on the unit for implements etc. Any other ideas for this?

#1. How was the pump driven: If it was direct
PTO shaft driven,(from the truck PTO) it may
not be usable with a "Side Load", such as a belt
or chain drive. That is: it may only have a bushing, instead of a roller or ball bearing
where the input shaft goes in..which will wear
and leak with a side load.
#2. How fast did it run on the truck? Some pumps
only run 600 to 1000 RPM on the truck, and put
out adiquate gallons per minute at those speeds.
Small engines are typically horsepower "Rated"
at 3600 RPM..if you tried to run a truck pump
that fast you"d have LOTS of gallons per minute
of flow..and unless you have VERY LARGE lines
you"d create lots of back pressure,(trying to
"Force" too much flow through small lines) and
need LOTS of horsepower to overcome that, PLUS,
create lots of HEAT!
#3. Finally..how much Horsepower did that truck
engine have??? Are you going to try to achieve
what a 250 Horsepower Cummins Diesel did..with
an old lawnmower engine ?
AND: what were you going to use for oil tank,
or reservior? A truck system can get by with a
small,(5 gallon) reservior, because it only runs
for a few minutes, putting a hoist/box up> then
it has time to cool off. If you want to run that
same system contionous, you"ll need large reservior capacity...2 to 3 times the GPM of the
pump, as a rule of thumb.
Vast plans start with half-vast ideas!

I appreciate your input Greygoat. This is why I posted my question. Yes the pump was direct drive off the transmission thru a 4' pto shaft. I have the resevoir off the truck which appears to be about a 15 gallons.

What greygoat said is true but can be over come.

Even if it was a direct drive you can set up a couple of pillow block bearings with a shaft on the same plate the motor is mounted on to create a drive shaft set up. Build it in such a way that you can change sprockets or pulleys to get the speed you want.

If you start with a 3 inch pulley on the motor to a 12 inch on the jack shaft will reduce the engine RPM"s from 3600 engine to about 900 at the shaft.

You may need more than a 15 gallon resevoir.

It may be able to made to work the way you want.

Gary

I really doubt that you can run that big pump on 16 HP engine.
Walt

I really doubt that you can run that big pump on 16 HP engine.
Walt

I too have a couple of pumps like that and I was thinking about using one to power my mini tank so your question came in handy sort of. I will have to ask a couple guys I know that build dump trucks and they might know what RPM they run at. I do know that the higher the RPM the higher the GPM is since if you kick the RPM up in a dump truck the bed goes up in relationship of the RPM. I.E. higher engine RPM faster the bed goes up

Here's a primitive set-up using a hoist pump to make a dump trailer. Local truck mechanic said the 8 HP briggs wouldn't spin it under load, so I geared it as low as I could with weld-on sprockets from the local farm store. It raises it easily at just above an idle, and seems to raise at about the same speed as it would if powered by the truck engine. I don't know the pressure, GPM, or RPM's. It's a twin post hoist, but single stage cylinders. I don't remember ever seeing two stage cylinders on a truck hoist. I've added another board to the sides to hold more wood, but I have never weighed it to see what it's dumping. In your case, you may need more volume and pressure. I picture what you're building is a stand-alone pump to free up a tractor. And like Greygoat said - a bigger tank would keep the oil cooler. This thing probably doesn't run but about a minute at a time, so cooling isn't an issue.

Paul

I made a dump trailer out of a 1-ton dump truck hoist and bed. I run it off the 2N ford tractor PTO which is 540 RPM but less at fast idle, which works good.

Remember that the PTO units on a lot of trucks are geared to give a PTO speed of the 540 rpm that is needed to run fertilizer spreaders and many a company did there custom spreading with those trucks with the fertilizer spreader on the pto.

There is all these good ideas but the MOST important is direction of rotation of pump. If run backwards it will not pump if setup for single rotation. Some will pump backwards with lines hooked up to run that way but will never keep shaft seal in it.

Shaun - I hooked mine up backwards the first time. Thought the pump was a dud. Swapped the sprocket to the other shaft and it worked like a new one. I thought the oil would go thru the center of the pump gears, but I learned that it goes around the outside.

Paul

Most of the transmission PTO's were geared to give 540 rpm, but very few were ever run at that speed.