logsplitter issues

[guiness1976]

I have an older 5.5 hp briggs powered horizontal splitter that stopped splitting with any pressure. It was running fine, I was splitting for an hour and then it would barely dent a log. I installed a gauge between pump and inlet of valve. Pressure against a log is about 200psi. Sometimes if I retract all the way and hold it, the pressure will build to 2200. Sometimes it does not build. If it builds that much pressure, the pump is probably working? Does this point to a valve issue? Thanks for any help, and for all the advice I've gotten from the archives.

 

[KsWoodsMan]

Low fluid level ?

Possibly clogged pickup screen?

Blown cyl seal ?

 

[drmiller100]

sometimes it builds, sometimes not.

probably a 2 stage pump where she ain't kicking down correctly.

 

[KsWoodsMan]

sometimes it builds, sometimes not.

probably a 2 stage pump where she ain't kicking down correctly.

Wouldn't the engine bog or stall if it wasn't kicking down to the high presure stage correctly? I could see internal leakage in the pump causing this though.

He said it would ony build pressure on retract. Kind of rules out internal leakage.

And, a plugged screen it probably isn't.

Low fluid level could mean it is sucking air and the retact wouldnt hold as much volume of air to have to compress. Taking less time to build pressure.

Blown/worn cylinder seal would allow fluid to escape in one direction while acting almost normally in the other direction. Sure it isnt perfect or it wouldnt take long for the pressure to build.

Check your fluid levels. If they are good diagnose the cylinder by removing the inlet fitting for the retract portion on the cylinder. Fully extend the ram. once it reaches its full extension of travel check to see if any fluid is escaping from the retract port. If so, time to rebuild the cylinder with some new seals.

If that isn't it then start to think about valve and bypass issues. I'm not a pro .. but this isn't rocket science either.

 

[guiness1976]

thanks for the ideas. The fluid level is good, and I will check the cylinder as advised.

 

[sredlin]

pump may be shot

 

[guiness1976]

Sorry I took so long, but I tested the piston as was suggested. Did I test it correctly? I started the engine, and fully extended the piston. I shut off the engine and removed the fitting on the wedge end of the piston. Then I tried extending the piston and fluid came pooring put of the front inlet on piston. If I did this correctly, then I should replace the piston seals. Right? Thanks for your help.

 

[leon]

wood splitter

Sorry I took so long, but I tested the piston as was suggested. Did I test it correctly? I started the engine, and fully extended the piston. I shut off the engine and removed the fitting on the wedge end of the piston. Then I tried extending the piston and fluid came pooring put of the front inlet on piston. If I did this correctly, then I should replace the piston seals. Right? Thanks for your help.

One question- did the oil come out under pressure? and if it did and it went all over the place it tells me you have bad pistion packing so have it(the cylinder) rebuilt

opcorn: :spam:

 

[guiness1976]

The oil only came out when I used the valve to actuate the cylinder. The oil came out at a pretty high volume but it didn't spray across the room as if it was at high pressure.

 

[leon]

splitter problems

The oil only came out when I used the valve to actuate the cylinder. The oil came out at a pretty high volume but it didn't spray across the room as if it was at high pressure.

Yup, you have bad piston packings, if your cylinder is junk-meaning a cylinder with no name plate or other issues I would just scrap it as a new one with good packing and warranty is well worth it.

If you trust your rebuilder make sure they measure the bore of the cylinder too as it may be worn beyond use and you need a new cylinder anyway- should be smooth with no DAMAGE INSIDE prince hydraulics makes good cylinders-just make sure you order and identical cylinder with the proper stroke and bore etc. and spend a little extra for the internal stop tube-not an external lock ring!!!!! you will lose an inch of stroke but the cylinder will last much longer with no oil leaks as the cylinder travel will be unaffected by minor bending from side stresses as there will be none.

Check the mounting pins and bushings as they may need to be replaced as well.


also be sure the hydraulic fittings do not protrude inside the barrel-instant cut packing and piston damage etc.
opcorn: opcorn: opcorn:



As splitter manufacturers buy off the shelf cylinders this in it self is problematic simply due to the fact that the cylinders do not have stop tubes to-one increase load bearing area of the piston and two to reduce stress on the rod and piston during its duty cycle/work cycle-

 

[guiness1976]

Looks like its a new cylinder for me. I appreciate the wisdom.

 

[Wood Doctor]

Looks like its a new cylinder for me. I appreciate the wisdom.

I doubt that. Cylinders seldom fail. Look elsewhere. Check all hoses first and the connections. Got a filter on the suction side? Check that. Might be clogged up. Also, what about the fluid level?

 

[guiness1976]

The fluid level is about 1" from the top of the tank, there is no suction filter.

 

[kevin j]

If the two stage was not unloading, it would kill the engine. Pressure would rise when cylinder stalled, have too much pressure at high flow for the engine to turn.

Not building pressure = either worn pump, or totally unloading somewhere, shaft not turning well, or big hole in system somewhere.

Is the pump coupling ok?

'pretty high volume' and 'under pressure' are subjective terms.
assuming you do not have a flow meter, try a bucket. How much oil comes out of the rod end hose when you did the test? pressurize the closed end (rod extend to stops, not while it is moving) and measure in a bucket. a cup or quart in how long? That is piston seal leakage. It can vary with stroke, sometimes it is good to stall the cylinder against a block of wood at various points in the stroke.

For only 200 psi you have to leak almost full pump flow across a hole somewhere. With 5.5 hp engine, let's assume you have an 11 gpm pump.

If you suspect the cylinder, cap the lines out of the control valve to cylinder. As soon as you cycle the valve against the plugs, the pressure should be at 2500, or whatever.

try that, then next step.

k

 

[guiness1976]

The pump coupling is exposed and is in good condition. I will get plugs tomorrow and try that test.Thanks.

 

[Wood Doctor]

The pump coupling is exposed and is in good condition. I will get plugs tomorrow and try that test.Thanks.

I still think it's something rather simple, primarily because it worked for awhile and then shut down. Sometimes a kink in the hydraulic line can cause this after it warms up, similar to what can happen to the fuel line in a chainsaw. Check to be sure there are no kinks anywhere. Then try to isolate where the fluid is stopping because you are not getting flow where you need it. Without fluid flow, the whole system cannot operate and the engine cannot tell you anything because it thinks everything is fine.

I am surprise dthe pump isn't making some sort of screeching noise. If you cannot see any leaks anywhere, then there has to be a fluid blockage, and the pump will usually tell you that there is a blockage in its own unpolite way.

 

[Jkebxjunke]

is there a suction strainer? if so I wonder if the screen is blocked..or the intake is blocked... or to expound on the kinked line idea.. how bout this the suction line could be collapsing internally... Is there a filter? could it be plugged?
just some random thoughts

 

[guiness1976]

Hi guys, sorry but I've been busy with work. I plugged the outlet ports on the valve, and the gauge hit 2200 in both directions. Does this leave the cylinder as the culprit?

 

[KsWoodsMan]

Yes.
The pump is good, the fluid was running past the seal in the cylinder.

If you are going to rebuild it be sure to check for scoring inside, remove all debris from the old seal and replace the filter.

Otherwise be sure you protect the new cylinder with a new filter.