Log Splitter question

wkpoor · Oct 6, 2008

If this pump were cavitating I would probably know it because the PTO mount allows for some slop on purpose. There is no chattering at all that I think would be there if it were sucking air. That might also show up in the cylinder. Everything operates glass smooth. Anyone who has split with me will vaulch for the speed and power of this setup. And I can regulate the amount of fluid in the oversize tank for winter or summer so my fluid stays where I want it. I couldn't be happier with how this has worked for me. Even if the book says it shouldn't.

Farmerford · Oct 6, 2008

I don't know your brand of quick disconnects, but I checked the specs on the 1" Parker QD I used to connect a backhoe to my JD 455D crawler/loader, with a 23gpm pump. They are rated for 50 gpm, and show a pressure drop of 15 psi at 50 gpm and 2 1/2 psi at 15 gpm.

The pump inlet pressure that causes cavitation varies according to the pump type and make. However, the accepted safe level for most gear pumps is 3 psi gauge vacuum at the pump inlet. That is the pressure setting on the bypass valve on my suction strainer and on the warning gauge.

If you have 15" of head in the reservoir (relative to the pump inlet), that adds about 1/2psi positive pressure. That mitered elbow going into the pump adds a bit of loss, but I haven't looked it up.

Seems to me that, at least once the fluid is warm and you operate the pump at about 2/3 normal 540 pto rpm, your net pressure drop (ignoring the short suction line and elbow) is probably 2 psi. Even at 540 rpm the net drop is probably no more than 4 psi, so you are probably okay, but without any margin for increase. If you have a strainer on the suction line, it should be cleaned regularly to avoid any pressure drop across it.

That is a neat looking splitter. Did you just wash it or does it really stay that clean? My hydraulic stuff is always covered with fluid and dust. Two lines burst on the backhoe Saturday and managed to cover me (and the machine) with fluid before I could get the thing stopped.

I particularly like the channels that hold the wedge. Do they ever get clogged with chips at the fixed end?

wkpoor · Oct 6, 2008

I don't know your brand of quick disconnects, but I checked the specs on the 1" Parker QD I used to connect a backhoe to my JD 455D crawler/loader, with a 23gpm pump. They are rated for 50 gpm, and show a pressure drop of 15 psi at 50 gpm and 2 1/2 psi at 15 gpm.

The pump inlet pressure that causes cavitation varies according to the pump type and make. However, the accepted safe level for most gear pumps is 3 psi gauge vacuum at the pump inlet. That is the pressure setting on the bypass valve on my suction strainer and on the warning gauge.

If you have 15" of head in the reservoir (relative to the pump inlet), that adds about 1/2psi positive pressure. That mitered elbow going into the pump adds a bit of loss, but I haven't looked it up.

Seems to me that, at least once the fluid is warm and you operate the pump at about 2/3 normal 540 pto rpm, your net pressure drop (ignoring the short suction line and elbow) is probably 2 psi. Even at 540 rpm the net drop is probably no more than 4 psi, so you are probably okay, but without any margin for increase. If you have a strainer on the suction line, it should be cleaned regularly to avoid any pressure drop across it.

That is a neat looking splitter. Did you just wash it or does it really stay that clean? My hydraulic stuff is always covered with fluid and dust. Two lines burst on the backhoe Saturday and managed to cover me (and the machine) with fluid before I could get the thing stopped.

I particularly like the channels that hold the wedge. Do they ever get clogged with chips at the fixed end?

Those are parker QD's as you guessed. I do power wash my stuff from time to time but those connections have never leaked a drop. The only place I see oil is the filler cap. There is no suction strainer on that unit. Only a return filter. And that probably wasn't needed in this closed system.
The channels did get clogged before I cut over an inch out of both sides (since that pic was taken last winter) right up against the toe plate. That solved the problem. Speeco addressed that issue in their updated beam by adding slots but I doubt they are large enough to allow all debris to fall through. I got to believe Prince Mfg. intended for that pump to be plumbed like I did because of the location. Otherwise the ports would be located in the rear and not the side. However the 40GPM 1000PTO model does have the ports in the rear and maybe that is the reason. I'm going into my 4th season with this setup and it is a pleasure to operate. In fact the splitter rarely leaves the back of that tractor. If I need to take it off I lower it onto a furniture dolly, remove hitch and hoses and roll the whole thing back against the wall in the shop. Takes all of 5min. to get it off or on. Speed is fa nominal and fuel is not an issue at all as I run the tractor exclusively on sumped jet A.

Diamondpilot · Oct 7, 2008

Here is a pic of a log splitter I made for my 3 point. I bought the beam off a wrecked tow behind unit then started fabricating. I did not like the store bought units since they only allowed access to one side of the splitter. I usually split with a buddy. I had to fabricate the frame, hitch, wedge, then put together the cylinder, hoses, and valve. I have about $400 in it. It goes horizontal and vertical and runs off my tractors hydro system. It will split anything I throw at it and I am guessing it has about a 6 or 7 second cycle time at 1300 rpm's.

Chris