Progress on Splitter rebuild

DO NOT put the filter on the intake line to the pump (Unless you really like purchasing new pumps...)

The ONLY thing that should be between the tank and the pump is possibly a fairly coarse filter screen, and many hydraulic people would even object to that. You want as straight and short a path from the tank to the pump input as you can manage, with minimal restrictions - NO fitting should be smaller than the pump inlet. Ideally the pump should be lower than the tank fluid level, but this isn't always possible, however you should at least attempt to minimize the suction head.

The reason is you want to make sure the pump suction side doesn't cavitate, and in effect make the pump run dry - this will rapidly ruin the pump. To avoid it, you want to make sure that there is no restriction in the suction line.

The filter should be in the low pressure RETURN line that goes from the valve back to the tank. Make sure you plumb it so the flow goes in the proper direction (it should have a flow arrow on the housing). It is probably best to put the filter so that it goes directly into the tank, preferably below the full line (reduces air bubbles in the fluid) and then attach the return hose to the filter as this minimizes the number of fittings needed.

Otherwise, your hoses need to be long enough to go from point to point without straining or excessively tight bends. If the splitter tilts, make sure the hoses work in both positions, and going from one to the other. Avoid twists in the hoses. Try to keep them as short as you can while meeting the other guides - make them as long as they need to be, but no longer...

Remember, the high pressure side - pump to valve, valve to cylinder (both sides) need to use high pressure rated hoses and fittings (3,000 PSI minimum working pressure, NO Schedule 40 plumbing fittings, no hose clamps, etc.) The low pressure side - valve to tank, tank to pump, can use any suitable oil resistant hose, and it is OK to use plumbing fittings, hose clamps and so on.

The valve needs to be solidly mounted - not just screwed into ONE of the cylinder ports - it is OK to have it screwed into one port and run a RIGID metal line to the other port, as this gives two solid points so that it can't turn. If not, you should make some sort of hold down bracket. Otherwise the constant cycling of the valve will cause it to loosen up and leak.

Hope this helps...

Good job on the rebuild job so far, looks good. (BTW, you mentioned a new pump and valve, looks like a new engine as well???)

Gooserider

I agree with your rebuilding plans...better off with the devil you know.

What Goose said.
Looks great so far!

Gooserider said:

It is probably best to put the filter so that it goes directly into the tank, preferably below the full line (reduces air bubbles in the fluid)...

Click to expand...

If the filter body is below the fill line, the oil will spill out when you unscrew the filter to change it. You can mount the filter body above the fill line and still have the return line below it.

That reminds me, I need to change the filter on mine.

Wow that looks awesome! Bet it looks better now than when it was built! Can I borrow it now?

Ray

LLigetfa said:

Gooserider said:

It is probably best to put the filter so that it goes directly into the tank, preferably below the full line (reduces air bubbles in the fluid)...

Click to expand...

If the filter body is below the fill line, the oil will spill out when you unscrew the filter to change it. You can mount the filter body above the fill line and still have the return line below it.

That reminds me, I need to change the filter on mine.

Click to expand...

True, if the filter itself is below the fluid level you might loose some fluid when changing the filter - I don't see this as a huge problem.

The point that I was trying to make though, is that it is better if the fluid goes back into the tank below the fluid level, as opposed to just spraying in the top. This will reduce the amount of foaming that can occur, and keeps the fluid from picking up a lot of air bubbles...

However most of us don't have a lot of choice in our tanks, since we have to deal with whatever the manufacturer gave us, so it's a case of doing the best you can with what you've got.

Gooserider

michaelthomas said:

I have a few questions as I progress...
When assembling the plumbing on a splitter project should the hoses be partially filled with fluid as the connections are made?

Click to expand...

No need, and would make things really messy!

I would imagine you would fill the filter with fluid prior to installing?

Click to expand...

It won't hurt, but if the filter is on the return line, again no real need (It will fill itself as soon as the unit fires up, and it doesn't do anything critical that needs lubing while it fills.

Pour fluid into the intake hose and into pump prior to final clamping?

Click to expand...

Normally I would say not, but in your case with the big pump suction head, it wouldn't hurt...

How much elevation will a 16gpm pump with a 1" inlet be able to overcome without cavitation. My pump is above the tank and suction pipe is on the other side of the deck from the pump. The intake hose will have to be routed over the cylinder to the pump. the pipe is 6" into the tank and extends about 10"out of the tank, then another 12" or so to clear the cylinder and then a down hill of about 12" into the pump inlet. Each time I start this will the inlet hose be partially empty because of gravity?

Click to expand...

That sounds like a really long and ugly run... is there any way you can avoid the up and down steps - possibly drill a hole in the web of the beam for the hose to go straight through? If you can't do anything to straighten out the run, at least make the bends very long and sweeping rather than sharp corners - remember that every bend adds considerably to the flow resistance - effectively several times the nominal length of the run.

What I have seen suggested to "prime" a splitter setup is to tie the control handle into the down position, and then pull the engine over by hand (ignition off, and you may want to pull the plug just to make it easier to pull) until the piston starts to move. Then start the engine (run it slow if you have an adjustable throttle) and cycle the piston up and down 10-12 times, with no load. Expect that the motion may be very jerky at first as the air gets purged from the plumbing (keep all body parts clear!), but it will smooth out - obviously keep an eye out for leaks, and stop if you see any. After that stop and check your fluid level - it will probably be down at least a gallon as this is what gets used to fill the pump, cylinder and all the hoses.

Once you have the system full, and purged the air, you should NOT have any significant drainage of fluid from the rest of the system into the tank - essentially there is no way for air to get back into the lines to allow them to drain without pulling a vacuum.

Note that when connecting the lines, some hydraulic fittings are compression type that should NOT have any kind of thread sealant applied to them, while others are NPT pipe thread, which should be sealed, I like to use pipe dope - my brand of choice is Rector-Seal, but which one isn't a big deal. Teflon tape can also be used, but be careful not to block any pipe ends with it, and to not allow fragments to get into the system, as they can cause problems for all the parts...

Gooserider

On my splitter the inlet is on the bottom side of the pump, with the outlet on the top, so I'm not quite sure I follow you. (and have been having trouble figuring it out from your pictures) Note that your pump's bolt pattern is symetrical, so you can rotate it if that will make the fittings line up better.

If those big pipes sticking up out of the tank are your suction and return fittings, then I would suggest shortenning the suction side, putting the pump with it's inlet either on the bottom or sideways, and running the suction line from the tank to the pump either under the beam or through the web - get rid of a lot of the extra plumbing with associated suction head issues.

On the filter, I assume you are putting it in the return line? If so, you want to have the filter be the same as the return line outlet on the valve.

Your plumbing should be something like this...

1. Tank to pump inlet - suction line, should be as short and straight as possible, MUST be a non-collapsible hose, must be as big as the pump inlet.
2. Pump outlet to valve - HIGH PRESSURE line - 1/2" minimum diameter, theoretically ideal is same as smaller of valve inlet or pump outlet, (usually 3/4") but that gets expensive, 1/2" will do the job.
3. Valve to cylinder (both ends) - HIGH PRESSURE lines, should be same as valve ports or cylinder connections, which ever is smaller, or 1/2".
4. Valve to tank, via filter - low pressure line, should be the same size as the valve outlet (probably 3/4") larger is OK, filter unit must have at least as high a flow capacity as the pump output, more is better.

The valve would be open centre so no pressure is expected to show with no load. When you bottom out the cylinder retract, you should see a pressure spike. A fully retracted cylinder holds less oil than a fully extended one so it's possible to overflow the reservoir. The oil will also expand with heat so expect more to overflow.

Normal full level for the hydraulic tank will be 1" - 1 1/2" below top of tank.

Looks great!

You should not show any appreciable pressure when the valve is in neutral. Maybe just enough to move the guage off the pin, but that's about it. Extending and retracting the piston w/o a log or other resistance, will show a little more, but not much - on my machine I show about 300 pounds when the system is stone cold, or about 150 when it warms up. If you keep holding the valve open when the piston hits full travel (in or out) the pressure should build till the relief valve opens, and you will probably also bog the engine a little.

When splitting, the pressure will vary depending on how tough the log is - an easy round will barely show any increase over what you have just moving the piston. A really gnarly chunk will show more. Essentially when you get into a tough chunk the wedge will slow down, and pressure will build until either the log lets go, or you pop off the pressure release, usually the log goes first...

As to the fluid level, unless you have a dipstick or other item that says otherwise, you want to have the fluid level an inch or two below the top of the tank when the system is at operating temperature. Hydraulic fluid does expand a significant amount when heated, so measuring it while hot is the best approach.

Keep the fluid level on the low side until you have everything sorted - remember that the plumbing holds a gallon or so, and if you have to drain it to fix something, that will raise the tank level. Once it's working you can top up as the plumbing should NOT drain when the machine is not in use.

Gooserider