Pto Log splitter

cheriecorey · Nov 30, 2009

Hi everyone

I have a Pto log splitter and I want to convert it to a gas engine. I want to remove the pto shaft and add a pulley to the pump and add a belt and gas engine. How big of a motor would it take and any other Ideas would be great.

Thanks i
Cheriecorey

rus_geek · Nov 30, 2009

Do you have the specs for the pump? Generally speaking, a bigger engine will give you more power and/or speed. Just like hooking up to the PTO of a 20HP tractor or a 120HP tractor will operate differently.

-r-

radioman · Nov 30, 2009

post a pic of your current setup. Is yours a screw type or hydraulic ?

J_J · Nov 30, 2009

You could put any pump and engine you want to on it. Most engine driven log splitters will have a two stage pump connected directly to an engine. If you have an 8 HP engine, you can use this pump . 16 GPM pump

https://www.surpluscenter.com/item.asp?UID=2009113015580836&item=9-7503-16&catname=hydraulic

If you have a 16 HP engine, you can use this pump. 28 GPM

https://www.surpluscenter.com/item.asp?UID=2009113015580836&item=9-4897&catname=hydraulic

This setup will produce about 15 ton of force.

This is assuming that the pump does not go into high pressure mode.

times will be about 2.79 sec to extend, and about 2.1 sec to return

Total cycle time= 4.81 sec

J_J · Nov 30, 2009

cheriecorey said:
Hi everyone

I have a Pto log splitter and I want to convert it to a gas engine. I want to remove the PTO shaft and add a pulley to the pump and add a belt and gas engine. How big of a motor would it take and any other Ideas would be great.

Thanks i
Cheriecorey

What so you mean about removing the PTO shaft, and add pulley to what pump? Do you mean that you have a PTO pump on the PTO shaft? If you have a pump, you need to know the displacement and pressure rating, and GPM.

Do you have something like this?

greg_g · Nov 30, 2009

cheriecorey said:
I have a Pto log splitter and I want to convert it to a gas engine. I want to remove the pto shaft and add a pulley to the pump and add a belt and gas engine. How big of a motor would it take and any other Ideas would be great

Shouldn't be a problem. But those PTO driven pumps are meant to be driven at 540 RPM. So choose your pulley carefully. Most small engines are governed at 3600 RPM, so you'll need about a 7:1 reduction pulley. Horsepower depends if you've got a one stage or two stage control valve. Two stage will let you get by with a smaller engine.

//greg//

cheriecorey · Nov 30, 2009

Thanks for the responses, I will have to do some research on the splitter. The actual pump is on the log splitter and is driven by a pto shaft to the tractor, I want to eliminate the tractor and pto shaft. Greg how do I determine if the control valve is a two stage or single stage?

Thanks
corey

greg_g · Nov 30, 2009

cheriecorey said:
Greg how do I determine if the control valve is a two stage or single stage?

Well, if you've used it before - it's simple. If piston extends rapidly until meeting resistance - then bears down like it's grabbed another gear - it's a two stage. If it travels at the same speed back and forth with no regard to resistance, it's a single stage.

If you have never observed it in operation, you'll have to try to determine the make and model - then start researching.

//greg//

cheriecorey · Dec 4, 2009

Good Day

Here is what I found out on the Pto pump on the splitter I have. I looked on the internet and they put an A behind the one. Can you tell me what would be the Minimum size gas motor I would need.

Thanks Corey

HC-PTO-1
Specs: Rpm: 540
Min Hp: 30
Displacement: 9.9
Inlet Port:1 5/16-12
Outlet Port:1 1/16-12
GPM @ 2000 psi: 21.0
Shaft Dia. (in.) 1 3/8 Dia, 6-tooth
Rotation Is Right

J_J · Dec 4, 2009

cheriecorey said:
Good Day

Here is what I found out on the Pto pump on the splitter I have. I looked on the internet and they put an A behind the one. Can you tell me what would be the Minimum size gas motor I would need.

Thanks Corey

HC-PTO-1
Specs: Rpm: 540
Min Hp: 30
Displacement: 9.9
Inlet Port:1 5/16-12
Outlet Port:1 1/16-12
GPM @ 2000 psi: 21.0
Shaft Dia. (in.) 1 3/8 Dia, 6-tooth
Rotation Is Right

It is not a two stage pump. It takes about about 29 HP to pump 21 GPM. with a pressure of 2000 psi. There are no two stage valve. There is an automatic log splitter valve , and there are detent valves.

An engine requires to run that pump would be about 29 HP. If you used another engine, you would have to us belts and pulleys to get the rpm down to 540 rpm. It might be less expensive to purchase a two stage pump and a 5, 8, 16 HP motor and connect it like a regular log splitter.

The displacement and rpm was disigned into that pump to produce the stated GPM.

greg_g · Dec 4, 2009

Prince LSR Rapid Extend Logsplitter Valve - Cylinder Services

J_J said:
It is not a two stage pump. It takes about about 29 HP to pump 21 GPM. with a pressure of 2000 psi. There are no two stage valve. There is an automatic log splitter valve , and there are detent valves.

Not a two stage pump, agree. No two stage valve, disagree. See http://www.princehyd.com/Portals/0/products/valves/LSR3060Flyer.pdf and Prince LSR Rapid Extend Logsplitter Valve - Cylinder Services

I have a SpeeCo three point hitch splitter powered by the tractor hydraulics. Clearly the tractor represents a single stage pump. Replacing the SpeeCo detent control valve with the the LSR3060 however, is all it takes to make it a two-stage operation.

//greg//

cheriecorey · Dec 4, 2009

Greg

so if I put that control valve on it what size motor could I get by with?

Thanks Corey

greg_g · Dec 4, 2009

I'll warn you that this is a guess, but I'd say at least 9 horsepower. Note that those spec sheets say minimum 30 horse when run by a tractor. That's cuz the PTO is direct drive (540 rpm). Remember I said when you use a 3600 rpm gasoline engine, you'll need a reduction pulley to cut that down to ~540 at the pump. Reducing the horsepower requirement similarly, drops it to a minimum 4.5hp. Double that for your throttle margin. Not very scientific approach, but that's how I came up with 9 hp

//greg//

J_J · Dec 5, 2009

greg_g said:
Prince LSR Rapid Extend Logsplitter Valve - Cylinder Services
Not a two stage pump, agree. No two stage valve, disagree. See http://www.princehyd.com/Portals/0/products/valves/LSR3060Flyer.pdf and Prince LSR Rapid Extend Logsplitter Valve - Cylinder Services

I have a SpeeCo three point hitch splitter powered by the tractor hydraulics. Clearly the tractor represents a single stage pump. Replacing the SpeeCo detent control valve with the the LSR3060 however, is all it takes to make it a two-stage operation.

//greg//

OK, it is two something. Call it two speed valve, or two stage. The data, does not say anything about shifting pressure, however it does increase volume, and that why it is called LSR rapid extend. It can not be used with a two stage pump. It essentially just about doubles the volume of hyd fluid. It lets the operator, manually shift from high speed mode to high splitting force mode. When the lever is first applied, it is in the full force splitting mode, and if you want it to extend faster, the lever is pushed further to the stop point

That pump as stated has a displacement of 9.9 cu in. and is designed to turn at a speed of 540. Whatever engine you add to the pump setup, has to put out 29 HP to get that volume, pressure,and GPM. The tractor had to put out that HP, and so will any engine used in it's place. If you use a 3600 rpm engine, it will have to be geared down to match the PTO rpm of 540. A 9 HP engine can not generate that much GPM.

A .3 cu in pump, at 3000 psi, at 3600 rpm, will pump 4.5 GPM, and require 9 HP

If you use one of those two stage pumps, you only need 5 or 6.5 HP

If you are going to use the current pump, you have to come up with 29 HP.

If you use one of those two stage pumps, you only need 5 or 6.5 HP engine

cheriecorey · Dec 5, 2009

Thanks Guys

Your info is very useful. Here is my situation. the log splitter is my father inlaws and he does not burn wood anymore at this point so I have had this splitter for the last 2 years and I ran it with a 27 hp tractor at idle, it will split just about anything you put at it. My Dad is a electric motor repair man and he knows how to clculate the pulley part of the conversion. We do not know hydralics all that well. So if we change the control valve to the one Greg refered to and put 10HP motor on it will it work? My father inlaw said I could put a motor on it but out of respect for him I would like to be able to switch it back to a pto splitter if he ever wants to burn wood again beacause it is a power splitter with the pto and he will always have tractor around. If I absilutly have to change to a two stage pump I will, but at a last resort.

Thanks Corey

greg_g · Dec 5, 2009

I believe a (minimum) 9hp gas or diesel engine, reduction pulleys, and a two stage valve will do what you want. But why modify it in the first place? Is it because you don't have a tractor any more? Cuz once you invest in what it takes to make the conversion, it's gonna be sort of a waste to return it to the OE configuration.

//greg//

J_J · Dec 5, 2009

cheriecorey said:
Greg

so if I put that control valve on it what size motor could I get by with?

Thanks Corey

This valve, LSR3060, has nothing to do with the HP requirement for the pump. It is simply a fast extend valve, and can not be used with a two stage pump.

If you use that pump. at max use, it will need 29 HP. If you use it at less, say 10 GPM, then you can use a small engine. and your cycle time will increase.

greg_g · Dec 5, 2009

JJ - are you considering that the reduction pulley is a force multiplier? A 9hp aux motor @3600 rpm delivers 9hp to the output shaft. Now gear down those RPMs by 67% (3600 to 540), and you effectively increase the delivery torque. It's like dropping from full throttle 4th gear down to to full throttle 1st. Same horsepower, but more torque. That's why I think a 3600 rpm 9hp (min) aux motor - transferring power through reduction pulleys to deliver 540 rpm - should be what it takes to satisfy this requirement.

//greg//

jenkinsph · Dec 5, 2009

I agree with JJ in that no matter what you do to gear this down you still need the 29 hp engine to deliver the high gpm's at 2000 psi.

That said I think the solution to the problem, if it may need to be converted back to a pto unit later is to buy or build what you want instead. I would decide whether or not you want gas or electric and decide how much you want to spend vs how big and fast it needs to be. I would go for a two stage pump setup with a 5 hp electric motor or 8 to 10 hp gas motor. You can likely buy one for less money and hassle.