Engine and pump sizing for wood splitter

   / Engine and pump sizing for wood splitter #21  
He is using a 4" bore cylinder not the more typical 5". 11 GPM on a 4" cylinder is pretty fast.

Around here, I would say that the 4" is the more "typical" setup.

From the common ~$1000 mfg's, I have only ever seen 11gpm with the 4" cylinder. The 4.5" I have seen both 11gpm (dads) and the 16 gpm, and the 5" bore I have seen both 16 and 22.

IMO. 4" and 11gpm is not "pretty fast"

I'm building a faster splitter just cause I want to.when you start looking at the bigger pumps you also need a bigger hydraulic tank just FYI .im building mine right into the I beam on the splitter trying for at least 10 gallons.and I'm using a vertical shaft riding mower engine this time

Yep. On a 2-stage pump its a good idea to have at a tank that matches the high flow. IE: 11gpm = 11 gallon tank, 16gpm = 16 gallon tank.

You "can" get by a little smaller given the duty cycle of the way most people run a splitter. But if you plan on cutting alot of wood, piling it up, then spend a whole day non-stop splitting 8-10 cord of wood, you want AT LEAST what I mentioned.

Any reason to use a 5" over a 4"? Both seem sufficient for the intended use. 4" is readily available locally is why I decided on that size.

Pretty much already been answered. Two things when it comes to cylinder sizing....power and speed. The bigger the bore, the more oil it takes to fill it....that takes longer. But there is more surface area to push against so it will have more power. With an 11gpm pump, I wouldnt even consider anything but a 4" cylinder.
 
   / Engine and pump sizing for wood splitter #22  
Oh, and here is some pics of my pump mounting:

IMG_20140322_162804_563.jpgIMG_20140324_143226_999.jpg
 
   / Engine and pump sizing for wood splitter
  • Thread Starter
#23  
So I'm a fan of using the engine I have, I guess I could sell the pressure washer and buy an engine.

So those of you that have used them, I live in Virginia, I split mostly Locust and Cherry, which can have very twist grain. I cut 16" lengths.

Do I need to upgrade to a 5" cylinder? If I do will an 8HP engine and 16gpm pump run it sufficiently?

If I dont up to a 5" cylinder I could still purchase the 8hp engine and run a 16gpm pump on the 4" cylinder. I just have never used a splitter and have a hard time deciding the specifics.

Upping to the 13Hp engine probably puts it outside my price range....so 6.5 or 8hp it is if I buy an engine. Which pump and cylinder?

The 6.5 horse engine is on sale for $99 bucks and give me 2 more HP than I have on hand but is it enough to up the pump size?

6.5 HP (212cc) OHV Horizontal Shaft Gas Engine EPA

8 HP (301cc) OHV Horizontal Shaft Gas Engine EPA

For the 13.6 GPM pump on the 6.5 it seems slightly under powered but I found several commercial version of this setup. Very confusing.

Also found this very helpful site for cycle times.

Log Splitter Speed Calculator by International Hydraulics
 
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   / Engine and pump sizing for wood splitter #24  
My splitter has a 10 gallon tank with a 11 GPM pump. My Dixie chopper only has about a gallon tank, but it has an oil cooler. I don't know the flow on it, but it is quite a bit to run two wheel motors.
 
   / Engine and pump sizing for wood splitter #25  
11gpm with a four inch cylinder will be fine. But if you don't already have almost everything laying around to build one it is hard to beat the price of a box store econo splitter.

If you are building your own it doesn't cost that much more to go to a 16gpm pump. Once you go up to 22gpm you should be using 3/4" lines and a good sized tank... At which point 28gpm with a bigger cylinder starts to look attractive.

A lot of have found good deals on garden tractor engines.
 
   / Engine and pump sizing for wood splitter #26  
28gpm is a quite a jump over 22. price jumps a good bit, need a larger valve, and dont work well the the 1/2" ports in most 4 or 4.5" cylinders.

Thats why I stopped at 22gpm / 4" cylinder combo. Because I would have to up to a 5" cylinder to get the larger ports to make use of the 28GPM pump that cost ~$150 more, larger valve, and slower cycle time overall.

To the OP: Havent split much locust, but cherry is easy splitting compared to other things. I'd stick with the 4". If you are at all worried, 4.5" cylinder is a nice fit with 16gpm. Dads 4.5" cylinder splitter has went through everything. Mine only occasionally has fits with nasty knotted elm. Just a matter of re-positioning.

Agree with the other poster, its hard to beat a $1000 unit ready to roll from TSC.

On my build, I already had a reservoir, axle, steel, beam, motor etc. All I needed was the hydraulics (pump, valve, cylinder, and misc hoses and filter). Just in those hydraulics I ended up with $900 or so. Granted, a 11gpm pump would have knocked off $100, but still, $800 just for the hydraulics and hoses. IF you have to buy anything else, axle, steel, etc you would be better off buying.
 
   / Engine and pump sizing for wood splitter #27  
I wouldn't say you are better off buying. I have slightly more than 1000 in my splitter but it is better than a similar TSC splitter.
 
   / Engine and pump sizing for wood splitter #28  
28gpm is a quite a jump over 22. price jumps a good bit, need a larger valve, and dont work well the the 1/2" ports in most 4 or 4.5" cylinders.

Thats why I stopped at 22gpm / 4" cylinder combo. Because I would have to up to a 5" cylinder to get the larger ports to make use of the 28GPM pump that cost ~$150 more, larger valve, and slower cycle time overall.

To the OP: Havent split much locust, but cherry is easy splitting compared to other things. I'd stick with the 4". If you are at all worried, 4.5" cylinder is a nice fit with 16gpm. Dads 4.5" cylinder splitter has went through everything. Mine only occasionally has fits with nasty knotted elm. Just a matter of re-positioning.

Agree with the other poster, its hard to beat a $1000 unit ready to roll from TSC.

On my build, I already had a reservoir, axle, steel, beam, motor etc. All I needed was the hydraulics (pump, valve, cylinder, and misc hoses and filter). Just in those hydraulics I ended up with $900 or so. Granted, a 11gpm pump would have knocked off $100, but still, $800 just for the hydraulics and hoses. IF you have to buy anything else, axle, steel, etc you would be better off buying.

A 28gpm pump costs $8 more than a 22gpm pump.

The difference between 1/2" and 3/4" ports is negligible when using 3/4" lines... A minuscule amount of heat will be generated from the slightly increased friction loss, speed will not be affected.

I'm using a valve rated for 25 gpm with a 28gpm but added a dump valve for $25 from ebay so that on the return stroke the oil bypasses the valve. Net result is I'm flowing less then 25gpm through the valve. Even without a dump valve people have successfully run a 28gpm with a 25gpm valve.
 
   / Engine and pump sizing for wood splitter #29  
I wouldn't say you are better off buying. I have slightly more than 1000 in my splitter but it is better than a similar TSC splitter.

I didn't mean to imply the box store splitter is better...just cheaper $$ since they often go on sale for less then a $1000
 
   / Engine and pump sizing for wood splitter #30  
I have split some pretty knarly stuff using a 4way wedge and 4in bore cylinder. I did upgrade my cyl to a 5in bore one and then the pump size jumped to the 28gpm two stage to make up for the speed lost with cyl upgrade. Found I have more than enough power for any thing i want to throw on the splitter, so next upgrade was converting the 4 way wedge to a 6 way. One man cant keep u with the splitter, heck It will make the tongues hang out with 5 men feeding and catching. Most folks dont need anything close to what I built, but I built it using mostly salvaged materials which kept the cost down. If i was starting a build from scratch, I think I wouldnt change much about the design I currently have. Nowhere have I seen any manuals or books that says I have to run the motor wide open and work like a maniac to process my wood. I do like the multi split wedges and the extra power when I need it. Just keep in mind that since you are starting from scratch with a new splitter build, that while a 4in bore cyl and a small pump will probably split 99% of everything you want to split, its that 1% of the time where you get a round stuck on the wedge and have to beat it off using a sledge hammer, that you will start second guessing your choices.

Personally, I am a glutten for punisment, I am building a processor using 2-4.5in bore cylinders and will be pumping close to 70gpm of oil thru it to make 12 way splits out of big rounds of wood. I like to process all my wood in one day and be done with it.
 
   / Engine and pump sizing for wood splitter #31  
A 28gpm pump costs $8 more than a 22gpm pump.

depends on brand and where you get it from I gess

The difference between 1/2" and 3/4" ports is negligible when using 3/4" lines... A minuscule amount of heat will be generated from the slightly increased friction loss, speed will not be affected.

I have no way to prove but I dont believe that speed wont be effected. My splitter runs slower than it should calculate out to be. Best guess is restriction in fittings. I dont think going to a 28gpm pump with my 1/2" fittings, 3/4" line, and 4" cylinder will yield any increase in speed over my 22gpm.

Math says i should cycle in 6.3 seconds. Its actually about 8. Math says a 28 gpm should cycle in 4.9 seconds, but I doubt it would be much quicker than the 8 seconds I am at now

I'm using a valve rated for 25 gpm with a 28gpm but added a dump valve for $25 from ebay so that on the return stroke the oil bypasses the valve. Net result is I'm flowing less then 25gpm through the valve. Even without a dump valve people have successfully run a 28gpm with a 25gpm valve.


Not saying it cannot be done, but I wouldnt. At least not without a dump valve. My splitter is a 4" bore and 2" rod. On retract stroke, I would need to force 37.2 gpm back through the 1/2" fittings and 25gpm valve. Whereas my 22gpm pump on retract only needs to force 29 gpm back though the valve and 1/2" fittings (which I believe is costing me some speed)
 
   / Engine and pump sizing for wood splitter #32  
So guys got a 14 horse koler I wanna use how big a pump and minimum gallons do I need .i have a new 11 gallon is it worth the upgrade on the new splitter ? I have a 4 inch cylindar
 
   / Engine and pump sizing for wood splitter #33  
So I'm a fan of using the engine I have, I guess I could sell the pressure washer and buy an engine.

So those of you that have used them, I live in Virginia, I split mostly Locust and Cherry, which can have very twist grain. I cut 16" lengths.

Do I need to upgrade to a 5" cylinder? If I do will an 8HP engine and 16gpm pump run it sufficiently?

If I dont up to a 5" cylinder I could still purchase the 8hp engine and run a 16gpm pump on the 4" cylinder. I just have never used a splitter and have a hard time deciding the specifics.

Upping to the 13Hp engine probably puts it outside my price range....so 6.5 or 8hp it is if I buy an engine. Which pump and cylinder?

The 6.5 horse engine is on sale for $99 bucks and give me 2 more HP than I have on hand but is it enough to up the pump size?

6.5 HP (212cc) OHV Horizontal Shaft Gas Engine EPA

8 HP (301cc) OHV Horizontal Shaft Gas Engine EPA

For the 13.6 GPM pump on the 6.5 it seems slightly under powered but I found several commercial version of this setup. Very confusing.

Also found this very helpful site for cycle times.

Log Splitter Speed Calculator by International Hydraulics

I just got a flyer today with the 13hp was $299.
 
   / Engine and pump sizing for wood splitter #34  
I split locust and I split cherry. Locust is way harder to split than cherry. Both can have twisted crotches, but the 5hp splitter still has no troubles with twisted up cherry. The only thing that's ever bogged it down was locust. And then I just turned the piece and try it again.
 
   / Engine and pump sizing for wood splitter #35  
So guys got a 14 horse koler I wanna use how big a pump and minimum gallons do I need .i have a new 11 gallon is it worth the upgrade on the new splitter ? I have a 4 inch cylindar

14hp will run the 22gpm pumps. certainly worth the upgrade over 11gpm IMO.

Would like to see 20 gallons for a tank
 
   / Engine and pump sizing for wood splitter #36  
I have no way to prove but I dont believe that speed wont be effected. My splitter runs slower than it should calculate out to be. Best guess is restriction in fittings. I dont think going to a 28gpm pump with my 1/2" fittings, 3/4" line, and 4" cylinder will yield any increase in speed over my 22gpm.

Math says i should cycle in 6.3 seconds. Its actually about 8. Math says a 28 gpm should cycle in 4.9 seconds, but I doubt it would be much quicker than the 8 seconds I am at now




)


The 28gpm pump will pump 28 gal a minute through a 3/4" port or a 1/2" port. There is not going to be an increase in speed from a larger sized port. The larger port will only decrease resistance and pressure drop. (Less heat)

Look inside of any hydraulic valve. The internal passages are a whole lot smaller then the fitting size yet does not decrease the pump output. Google Cv rating or flow coefficients if you want to understand more.
 
   / Engine and pump sizing for wood splitter
  • Thread Starter
#37  
The other option I have is to use all the steel I already have and build a splitter for my tractor.

I have a 40hp Gas Ford 2000. Mid 70's vintage. Runs excellent.

I could save the money of the engine and pump and couplers. Not a small difference, if I ran a PTO hydraulic pump and had my oil tank and lines on the splitter. I always split around my shed anyway. Doesn't seem that much different from an ease of use stand point. Plus it's one less engine to maintain.

Opinions?

I have no idea how much a PTO driven hydraulic pump would be but when factoring in engine, couplers and pump costs. I wouldn't think it would be terribly more or less.

Thoughts.
 
   / Engine and pump sizing for wood splitter
  • Thread Starter
#38  
Also. Is there anyway to use my tractors internal pump? Have no idea.
 
   / Engine and pump sizing for wood splitter
  • Thread Starter
#40  

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