Woodsplitter

[Secondaryburns]

Good day folks i need some help with a woodsplitter i built.The hydraulic oil gets hotter than i would expect.In the summer time when its 25degrees celcius i cant keep my hand on the hydraulic fittings they get that hot.6.5hp,4"x24" ram,2stage pump,10gal resevoir,detent valve.All the lines are 1/2" except for the suction which i believe is 1.25".Any thoughts or experience on this?Also i just installed a pressure guage to see what the relief is set for,with the cylinder extended fully the guage reads around 2300psi which seems correct.A friend told be that the valve or pump could be bypassing causing heat?And my valve should be an open center valve meaning the fluid flows directly through the valve.My valve doesnt apear to be built that way,i cannot see through the inlet or outlet

 

[Jags]

If you still have the pressure gauge in the system take a reading when you are not pushing or pulling. At "rest" you should be reading very little pressure. If you do see pressure at rest you may not have a proper type valve or possibly some other restriction in the system. This will cause higher temps.
Edit: your pressure reading needs to be taken between the pump and valve.

 

[Secondaryburns]

If you still have the pressure gauge in the system take a reading when you are not pushing or pulling. At "rest" you should be reading very little pressure. If you do see pressure at rest you may not have a proper type valve or possibly some other restriction in the system. This will cause higher temps.
Edit: your pressure reading needs to be taken between the pump and valve.

Thank you sir for trying to help greatly appreciated
With the engine running at full throttle,and valve in neutral position the guage reads zero psi.Pressure guage is mounted to the inlet side of the valve.Between pump and valve.

 

[gzecc]

A picture of the setup may help. Obviously 90 deg turns, and smaller hoses cause friction. What's the GPM on your pump?

 

[Secondaryburns]

A picture of the setup may help. Obviously 90 deg turns, and smaller hoses cause friction. What's the GPM on your pump?

Thanks.I will post pics of the splitter tomorrow.This is the only tag on the pump.

 

[Isaac Carlson]

Looks like an 11 or 13 gpm pump (Some of them screw up the numbers).

I an guessing you have a restriction somewhere. Post pictures of your setup from different angles so we can see everything.

 

[Jags]

Zero PSI at rest doesn’t sound like much of a restriction. I am beginning to wonder about the relative term “hot”. How hot is it? It’s pretty tough for most people to hang onto something at 120F, yet hydro juice is just fine at that temp.

 

[Isaac Carlson]

Zero PSI at rest doesn’t sound like much of a restriction. I am beginning to wonder about the relative term “hot”. How hot is it? It’s pretty tough for most people to hang onto something at 120F, yet hydro juice is just fine at that temp.

It could be a restriction in his cylinder lines, since the open circuit is fine.

120 is a good temp, and even 140 is ok, but that's about the limit. Going higher just breaks down the fluid faster. How long can you keep your hand on it?

I have seen fitting that are wide open and some are choked off. I depends on who made them. I like to drill them out bigger for less restriction. 90⁰ fittings are sometimes counted as restrictions when doing hydraulic calculations because the fluid is not flowing through them smoothly. There is a lot of turbulence in a 90⁰ fitting. A 45⁰ fitting is much better in that sense, and I use them where possible/practical.

I plumbed my entire house with 45's except for one line. That line doesn't flow nearly as well as the others. It's certainly not bad, but You can tell the line is restricted by the 90's.

 

[Secondaryburns]

It could be a restriction in his cylinder lines, since the open circuit is fine.

120 is a good temp, and even 140 is ok, but that's about the limit. Going higher just breaks down the fluid faster. How long can you keep your hand on it?

I have seen fitting that are wide open and some are choked off. I depends on who made them. I like to drill them out bigger for less restriction. 90⁰ fittings are sometimes counted as restrictions when doing hydraulic calculations because the fluid is not flowing through them smoothly. There is a lot of turbulence in a 90⁰ fitting. A 45⁰ fitting is much better in that sense, and I use them where possible/practical.

I plumbed my entire house with 45's except for one line. That line doesn't flow nearly as well as the others. It's certainly not bad, but You can tell the line is restricted by the 90's.

It gets hot,i checked in the late fall and it was around 180 after a couple hours of use.Cant hold your hand on anything.I can only run it half throttle to keep the heat down some.Burned a pump up 2 years ago.Replaced pump,new oil,even tried a larger tank with different plumbing and baffles cause i thought i was getting cavitation.I removed all the 90* fittings as well.All hoses are 1/2" however i havent drilled any fittings as of yet.I checked today it is a 15.2/3.3 gpm pump.

 

[Secondaryburns]

pics to come

 

[ericm979]

Drilling out hydraulic fittings that will be subject to high pressure seems risky to me. I'd go bigger instead. But even with larger hoses you will be limited some by the fittings on the pump, cylinder and valve.

"Open center" doesn't mean that you can see through it. It means that it flows from the input port to the tank port when in the neutral position. You can try blowing air or running low pressure oil through it to see if it's open. Or you can look for the manufacturer and model # on the valve and then look it up. It's possible to convert some valves between closed and open center.

Here's a useful diagram and article from a different forum. I don't know if you'll be able to read it if you're not a member but it's worth a try: (broken link removed to https://www.tractorbynet.com/forums/attachments/log-splitter-jpg.772143/)

 

[Secondaryburns]

Drilling out hydraulic fittings that will be subject to high pressure seems risky to me. I'd go bigger instead. But even with larger hoses you will be limited some by the fittings on the pump, cylinder and valve.

"Open center" doesn't mean that you can see through it. It means that it flows from the input port to the tank port when in the neutral position. You can try blowing air or running low pressure oil through it to see if it's open. Or you can look for the manufacturer and model # on the valve and then look it up. It's possible to convert some valves between closed and open center.

Here's a useful diagram and article from a different forum. I don't know if you'll be able to read it if you're not a member but it's worth a try: (broken link removed to https://www.tractorbynet.com/forums/attachments/log-splitter-jpg.772143/)

Thank you.However i am not a member.So the oil does flow thru the valve and to the tank when valve is in neutral.And reads zero on pressure guage

 

[Isaac Carlson]

180° is pretty hot. That'll burn ya. Your tank is a cavitation monster, as I call them. I prefer a round tank with tangent suction and return locations. I used a 20 lb propane tank and welded bungs in the right places and that fixed the cavitation and high temps. I can get some pics if you want. The fluid spins and that helps feed the suction line and eliminates the possibility of a suction vortex forming. The hot oil flows right against the side of the tank as it returns for instant cooling. Even in the summer, my temps are around 100-120° F. The tank holds about 4 gallons, which is more than enough. I think I could easily get by with a 2-3 gallon tank. I'm running ~12 gpm.

I'm curious how big the cylinder holes are. The threaded part is welded on over a hole that's drilled in the cylinder wall. If they are too small, that would make some heat. You could pull a hose off the cylinder and take a look. Take a video of it running and cycle it a few times so we can hear the load on the motor and any hydraulic noise.

Also, how big are the holes in those hose adapters?

 

[Secondaryburns]

Thank you for the info and help with this.Its been a struggle.I also had a larger hydraulic tank on it,with inlet and filter in the bottom of one end,baffles,and outlet to the punp in the other.Had well over 10gal of oil and it still got hot so u couldnt touch it.It never made any difference in heat generation.So i put the original smaller tank back on,which is the one you see in the pics.
I will get some more pics and video tomorrow of it running,psi,cylinder and adaptor sizes

 

[Secondaryburns]

180° is pretty hot. That'll burn ya. Your tank is a cavitation monster, as I call them. I prefer a round tank with tangent suction and return locations. I used a 20 lb propane tank and welded bungs in the right places and that fixed the cavitation and high temps. I can get some pics if you want. The fluid spins and that helps feed the suction line and eliminates the possibility of a suction vortex forming. The hot oil flows right against the side of the tank as it returns for instant cooling. Even in the summer, my temps are around 100-120° F. The tank holds about 4 gallons, which is more than enough. I think I could easily get by with a 2-3 gallon tank. I'm running ~12 gpm.

I'm curious how big the cylinder holes are. The threaded part is welded on over a hole that's drilled in the cylinder wall. If they are too small, that would make some heat. You could pull a hose off the cylinder and take a look. Take a video of it running and cycle it a few times so we can hear the load on the motor and any hydraulic noise.

Also, how big are the holes in those hose adapters?

Yes would like to see pics of propane tank if possible thanks

 

[Isaac Carlson]

I'm sitting here looking at your pictures thinking something doesn't look right, and I notice some of the hose ends look super small. I am very curious to find out the inside diameter of the fittings.

Here are some pictures of mine. The 90's are high flow and the oil is just nice and warm after a day of splitting. I can hold my hand on the tank indefinitely when it is up to temp. It's nice in the winter because you can warm your paws.

 

[ericm979]

At long as the suction and inlet are not right next each other in the tank it should work ok.

Looking at the pics I see that you put reducers on the pump output and the valve ports in order to use 1/2" hose. I think you should redo it with larger hoses that are closer to those port sizes. The pump manufacturer made the port that size for a reason. It looks like the cylinder has 1/2" ports, or at least there is no reducer there. You may be limited by the cylinder ports but you can reduce down to 1/2" right at the port. A short length of small diameter pipe with a bunch of large diameter pipe will flow better than a the same length of small pipe.

If it's still too hot maybe you can find a hydraulic shop who can replace the ports on the cylinder with larger ones.

Is that cylinder intended for splitter duty or did you adapt it from a different use?

 

[Isaac Carlson]

At long as the suction and inlet are not right next each other in the tank it should work ok.

Looking at the pics I see that you put reducers on the pump output and the valve ports in order to use 1/2" hose. I think you should redo it with larger hoses that are closer to those port sizes. The pump manufacturer made the port that size for a reason. It looks like the cylinder has 1/2" ports, or at least there is no reducer there. You may be limited by the cylinder ports but you can reduce down to 1/2" right at the port. A short length of small diameter pipe with a bunch of large diameter pipe will flow better than a the same length of small pipe.

If it's still too hot maybe you can find a hydraulic shop who can replace the ports on the cylinder with larger ones.

Is that cylinder intended for splitter duty or did you adapt it from a different use?

There is no way those cylinder ports are 1/2". The whole thing looks pieced together. It would be best to upsize the line from the pump to whatever the pump and valve are, put bigger fittings on the cylinder (or just get one with bigger fittings), and get rid of the reducers.

The pump is either 11 or 14.5 gpm according to the sticker, and that's too much for what look like 3/8" fittings. I have seen cylinders with 3/8" or 1/2" fittings welded over a little tiny hole. That may be a factor here as well. Either way, the fluid is overheating and restriction is most likely the cause.

Does the splitter move quickly through the wood? A blown piston seal could heat the fluid.

 

[Jags]

If you cycle the cylinder back and forth (not splitting), is there any noticeable drag on the engine? A restriction causing that much heat should be a noticeable drag on the engine, I would think.

 

[Isaac Carlson]

If you cycle the cylinder back and forth (not splitting), is there any noticeable drag on the engine? A restriction causing that much heat should be a noticeable drag on the engine, I would think.

I'm hoping we can hear something change, but it really doesn't take much restriction to heat the fluid. Just curculating hydraulic fluid in neutral will warm it up. If his seals are good, I'd put my money on the cylinder ports and small hose ends.

 

[Jags]

It would be interesting to have a gauge in the system just prior to the push Port of the cylinder. This would give a good indication of no load back pressure being created

 

[Secondaryburns]

Im gonna try and post a video.However you folks made an interesting point which has me wondering.This ram is off a factory 3pt hitch splitter.Perhaps its not rated for the gpm my independant pump puts out?

 

[Secondaryburns]

I took a 15 sec video and site says its too large to upload

 

[Secondaryburns]

pics

 

[Secondaryburns]

These are the 1/2" lines and ports of the 4x24 cylinder.The pump takes 1/2" npt,and valve takes 3/4" npt.I have 1/2" line running to everything.
When running engine at full throttle,extending the ram pressure comes up to about 150psi no load.Retracting runs about 200psi.Wish i could post the video