# Help, log splitter wont split



## LoggHog (Sep 21, 2010)

just bought a used 20 ton log splitter last year thing runs great it just wont split logs well. the ram cycles fine, but as soon as it hits the log it stops pretty much. if i rev the moter i can get usually get it to go through but it shouldnt be that way. anyone know how i can diagnose/fix the problem? thanks


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## triptester (Sep 21, 2010)

More info would help. Brand, motor size , cylinder size, pump type, and gpm.

You mentioned it splits when you rev the engine, this could be a sign that the engine is weak. Most engines develop maximum horsepower at near full throttle. Splitters are designed to be run at full throttle. The engines used on most splitters are the same as the ones used on lawn mowers.


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## dingeryote (Sep 22, 2010)

Run full throttle.+1
Partial throttle is for when you have to run and take a leak.

Check/replace the filter and look for kinks and obstructions on both sides.
Cranky valve maybe?

Who made it and what motor?


Stay safe!
Dingeryote


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## turnkey4099 (Sep 22, 2010)

I wouild be looking at the pump or cylinder. Motor problem would show as dying under load or slowing way down under load.

Cylinder may be leaking past the seals, pump may be doing the same.

Harry K


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## BlueRidgeMark (Sep 22, 2010)

What's going on here, boys? Three replies and not one of you welcomed the new guy! Where are your manners?



So, WELCOME, LoggHogg! 


Now get to work!


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## LoggHog (Sep 22, 2010)

Thanks for the welcome!

Here's more info on the splitter.

It's a Duerr Pro20 vertical/horizontal. Its got a 5" cylinder, and a 5 hp Briggs and Stratton runs it. The pump is also a Duerr but I don't know the gph. When I mentioned I had to rev. the motor to get through a log, I already had it wide open but i can push the throttle and REALLY rev it. It has a brand new filter, all hoses look good. 
I found some adjustment screw things on the pump and control valve, and after messing with them a bit I made the ram go really slow but it would go through the log. It cycled so slow though I might as well use a maul.
I don't know enough about hydraulics to determine where the problem might be. Any more help would be much appreciated. Thanks again.


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## woodhounder (Sep 24, 2010)

I agree with dingeryote run it full throttle, that is what they are made for.
Welcome to AS


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## ZeroJunk (Sep 24, 2010)

There is a pressure relief valve in the control somewhere, probably no more than a spring loaded device under a large hex nut. Take it out, clean it, and make sure there is no trash keeping the fluid bypassing all the tilme.


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## sawkiller (Sep 26, 2010)

A 5 hp motor on a 5" cylinder? That is gonna cycle pretty slow or kill the motor depending on pump size. If it is a 2 stage pump and it most likely is on a 5 hp motor you may only be getting 1-2 GPM on the second stage of the pump and while it should have the power to split a volkswagen it is not going do do it quickly with that setup.


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## Pulp Friction (Sep 26, 2010)

This could be simpler than you think. Sounds like the coupler set-screw between the engine and pump is slipping under loading. Please post what you found. And welcome to AS. I'm new here too.


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## alleyyooper (Sep 26, 2010)

What kind of pressure readings on the gauge are you getting when spliting?

 Al


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## LoggHog (Sep 27, 2010)

alleyyooper said:


> What kind of pressure readings on the gauge are you getting when spliting?
> 
> 
> Al


There isn't a pressure gauge on the splitter.



ZeroJunk said:


> There is a pressure relief valve in the control somewhere, probably no more than a spring loaded device under a large hex nut. Take it out, clean it, and make sure there is no trash keeping the fluid bypassing all the tilme.



There are 2 large hex nuts on the control valve one on the back and one on the top. which should i try? The one on the top looks like a stack of nuts with a small hole in the very top one. The one on the back (the larger one) if I remember right has an adjustment screw underneath. I think this is the one that i messed with that made the ram cycle very slow. Will springs and stuff come flying out if I remove one of these?



sawkiller said:


> A 5 hp motor on a 5" cylinder? That is gonna cycle pretty slow or kill the motor depending on pump size. If it is a 2 stage pump and it most likely is on a 5 hp motor you may only be getting 1-2 GPM on the second stage of the pump and while it should have the power to split a volkswagen it is not going do do it quickly with that setup.



I dont believe that it is a 2 stage pump. The motor never dies when the ram hits the log. It just grunts trying to get through it but never does unless I push the throttle connection right on the carb and rev the thing *WAY* *up*. Doing this I'm afraid I will blow the motor up one of these times. The man I bought it from "claimed" it would split through anything back when he used it. I believe it sat in his barn unused for quite a few years. I also remember him saying he never ran it at full throttle unless he had a really tough knotty log.



Pulp Friction said:


> This could be simpler than you think. Sounds like the coupler set-screw between the engine and pump is slipping under loading. Please post what you found. And welcome to AS. I'm new here too.



The set screws for the love-joy couplings are tight and also keyed. I also thought that might be the problem because the rubber spider thing was damaged between the couplings


Another thing I've noticed that when i return the ram, it has a "auto" return, that the lever doesnt pop back to the center position when the ram is fully retracted. It keeps trying pull the ram in. If that makes sense. 


Any suggestions on how I can talk the wife into letting me buy a new one?

puzzled and frustrated,

LoggHog


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## sawkiller (Sep 27, 2010)

Tell her I will give you $100 for your old one.

It sounds as if your problem may be in your valve or it also could be a bad pump? Without a pressure gauge tried in a few places we are just throwing out possibilities. The fact that changing the motor rpm makes it move makes me wonder if it is the pump? One other thing does the system have air in it or in other words is the pump airlocked? What does the fluid and filter look like?

Also zerojunk brings up a very good point and that may very well be the problem? I would lookup your regulator/control valve on line for proper adjustment and disassembly schematics. Most regulators must be tightened or screwed in to increase pressure although I am not familiar with yours. And most of the regulators I have rebuilt the spring is unloaded by the time you get the screw all the way out but they were water pressure regulators and once again I am not familar with yours.


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## alleyyooper (Sep 28, 2010)

With a 5HP moter the pump is most likely a two stage one. I would plumb in a pressure gauge so you can see wht the pump is pushing when trying to split.

As for getting the wife to allow you to buy a new one!!! Fat chance on US:biggrinbounce2: being able to do that if you can't.

 Al


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## Swamp Yankee (Sep 28, 2010)

I think you've answered your own question

If the splitter works fine with the engine at full throttle there isn't an issue as that's where the systems are deigned to operate. Horsepower is a function of torque multiplied by rpm. In order to make decent horsepower, especially on a small engine, the rpms need to be high.

Take Care


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## AKKAMAAN (Sep 28, 2010)

LoggHog said:


> just bought a used 20 ton log splitter last year thing runs great it just wont split logs well. the ram cycles fine, but as soon as it hits the log it stops pretty much. if i rev the moter i can get usually get it to go through but it shouldnt be that way. anyone know how i can diagnose/fix the problem? thanks



When "it stops"...is that the ram that stops or is it the engine that is bogging down??

If engine is bogging down, other posters are right, you need more power at higher rpm's...

If engine just keep running and ram stops, flow is bypassing some where, most likely through the relief valve.....

If this problem occurred suddenly, it is very possible there is some debris stuck in the relief valve that keeps it partly open, that explains the fact that it split when rpm's (flow) is increased....when increasing flow through that little opening in the relief valve, the pressure will increase enough to move the ram....

Do not keep running splitter like this, there will be over heating problems.....

2c


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## jags (Sep 28, 2010)

AKKAMAAN said:


> When "it stops"...is that the ram that stops or is it the engine that is bogging down??
> 
> If engine is bogging down, other posters are right, you need more power at higher rpm's...
> 
> ...


Akkamaan is on to it. You have a pressure problem. That is also why the auto return detent is not popping back into the center position. Your not creating enough pressure. Two things will cause low pressure.

1.) pump is not creating enough pressure.

2.) pressure is escaping somehow. Worn seals, pressure release valve, etc.

I would start with the valve body/ relief valve and look for crud as was said above. From there it is either seals in the cylinder or the pump. At least that is how I would attack it.


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## gandrimp (Sep 28, 2010)

Figure out which hose is your extend on the cylinder. Run the cylinder all the way extended. Take loose the other hose and aim it in a bucket ( it will help to have a second set of hands for this ), then try to extend the cylinder. If oil comes out of the hose then you have a cylinder that needs a kit. No gauge needed for this test and it should only take 5 minutes to do. If no oil you have now eliminated the cylinder as a problem.


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## jags (Sep 28, 2010)

gandrimp said:


> Figure out which hose is your extend on the cylinder. Run the cylinder all the way extended. Take loose the other hose and aim it in a bucket ( it will help to have a second set of hands for this ), then try to extend the cylinder. If oil comes out of the hose then you have a cylinder that needs a kit. No gauge needed for this test and it should only take 5 minutes to do. If no oil you have now eliminated the cylinder as a problem.



That is a very good idea to test the cylinder. I will tuck that one into my bag of tricks. Thanks.


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## AKKAMAAN (Sep 28, 2010)

gandrimp said:


> Figure out which hose is your extend on the cylinder. Run the cylinder all the way extended. Take loose the other hose and aim it in a bucket ( it will help to have a second set of hands for this ), then try to extend the cylinder. If oil comes out of the hose then you have a cylinder that needs a kit. No gauge needed for this test and it should only take 5 minutes to do. If no oil you have now eliminated the cylinder as a problem.



Do not forget to cap the work port on the control valve.....back pressure on return will make oil flow out


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## LoggHog (Sep 29, 2010)

Well I totally disassembled and cleaned the control valve tonight. That doesn't seem to be the problem.

After doing so I realized that the adjustment screw I spoke of earlier, that made the ram cycle faster or slower, was actually on the pump not the valve. 

Not sure if that matters or not as far as any ideas go. 

Also I think it is probably a 4" cylinder not a 5". 

I am going to try the cylinder test next, if its not that then i'm guessing its probably a bad pump. 

Is it possible to disassemble the pump and determine if its bad and repair it or would i have to buy a new one?


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## amateur cutter (Sep 29, 2010)

Many pumps do have a pressure relief built into them, prolly what you're looking at. Disassemble it carefully, & clean. Put it back together & adjust it slowly, & see what happens. As was stated, a small piece of debris can cause flow by, & lower the pump pressure dramatically. A C


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## meatwagon45 (Sep 29, 2010)

The first place I would look is the hydraulic fluid level. I know on my splitter, when the fluid is low it will not split a log. Since it sat, the fluid could have gummed up or leaked out and you would not know it if it dried

Just my 2 cents


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## triptester (Sep 30, 2010)

The Duerr Pro 20 splitter i believe has a haldex/barnes 11gpm 2-stage pump. These pumps are not rebuild-able replacement parts are not available. There is a ball check between the two pump section which could have a piece of debris that could keep the check from completely closing, or the pressure relief in the pump could also have some debris stuck in it.
Attached is a pic of a haldex/barnes pump


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