Wood Splitter Down On Power

[jwatts8275]

I bought an older wood splitter which I think should have plenty of power but it just doesn't. It has a 16hp Briggs engine, the cylinder is 4 1/2" X 34" with a 2 1/2" rod, a Gresen spool valve, 12 gal. hydraulic tank but I'm not sure about the output of the pump. It (pump body) measures 5 1/2" L, 4 1/2" W, 5" H and has 1" ports. The motor runs great and the cylinder has just been rebuilt. With these components I thought it would split just about anything you could throw at it. But the very first time I ran it I tried splitting a piece of Doug fir with a big knot in it and it bogged down when it got to the knot. The psi was about 1500 when the motor started bogging down. I thought it would put out about twice that.
One thing I've noticed is although the pump has a 1" outlet port the fitting on the pump end of the outlet hose reduces down to 1/2" od. Do you think the reduction in hose size coming out of the pump is limiting the output of the pump? Do pumps get weaker with use? Obviously I don't know very much about hydraulic components so I would sure be grateful for any help offered.

 

[triptester]

If the engine is bogging down then it is probably because the pump is to big for the engine. If the pump wasn't working the engine would not bog. A 16hp. engine will handle only about a 8 gpm single stage pump. The same engine will be able to power a 28 gpm 2-stage pump.

Attached is pics of typical 2-stage pumps.

 

[blades]

With out Identifing the pump, and weather it is a single or two stage limits the amount of help we can provide. if it is a two stage then it is not stepping into the second stage. The 1/2" output is standard on 11gpm pumps generally used for this application.

 

[jwatts8275]

Thanks very much for responding. Sorry but I've been gone a couple of days.
The pump is a single stage. Any idea where I could buy a two stage, new or used, at a reasonable price? What gpm rating would be right for my setup?
Thanks again.

 

[avalancher]

Thanks very much for responding. Sorry but I've been gone a couple of days.
The pump is a single stage. Any idea where I could buy a two stage, new or used, at a reasonable price? What gpm rating would be right for my setup?
Thanks again.

With the engine you got, you shouldnt have any problems powering a 22gpm pump.Widely available on the net, start with Northern tools. here is a handy link for ya.Same pump that I bought for the splitter that I am building, and I only have a 12hp Briggs.
Haldex Hydraulic Pump — 22 GPM, 2-Stage, Model# 1080035 | Pumps | Northern Tool + Equipment

If you really wanna go big, try the 28gpm pump,but beware of a few things.You are probably going to have to replumb the thing if you go this size.Hose and fittings may have be changed out to accomadate the larger flow, and depending on the type of valve, you might have to change it out as well.Personally, I would stick to the 22gpm,but if you want, here is the bigger pump.
http://www.northerntool.com/shop/tools/product_200321059_200321059

 

[goof008]

While it is most likely the pump being to big for the engine, it COULD be a dirty or out of tune carb. A carb will function well enough at no load WOT, but when a load is introduced it can bog down/sputter.

I would go with a 2 stage pump based on the size cylinder/stroke you have

I would also take off the carb and clean it...it's easy, and with the ethanol in gas these days, it's often needed!