Wood splitter problem. Experts in here please!

[bigfrank]

A friend bought a used Troy-Built 33 ton splitter. Got it home and couldn't get it to split oak. It acts like the second stage of the pump isn't working. The ram starts into the log then boggs the engine, with no second stage coming on.

We pulled the filter and screen and they were fine. Fluid level is correct and fresh. Pulled the pump and disassembled. Inside looks clean, Orings intact except for one that had a small flat spot on it, which we replaced. Bypass valve and pressure sensor were clean and seemed to be working when actuated by hand. No play in gearing. Reinstalled and same problem. The pumps are pretty straight forward and simple. Not much in there that looks like it could go wrong except for Orings.

We are at a loss. Can't figure out what it could be. Hope some of you had a solution. Thanks..

 

[Hinerman]

@Douglas Ostrander
@srcarr52

 

[Deets066]

Are your pump and valves adjusted correctly?

 

[Douglas Ostrander]

I would put on a pressure gauge on the base of the cylinder to see if the second stage is kicking in. Sounds like the pump is not kicking down to low flow high pressure. Or just try a new pump. The unloading valve may be stuck. If pressure does not go above 1000 psi the pump is not kicking down. Some pumps are adjustable when it kicks down. Check the adjustment if it has it. If over adjusted it can't build enough pressure to kick down to the low stage.

 

[Stump Shot]

If your pump pressure checks out, look at your cylinder cups.

 

[bigfrank]

Are your pump and valves adjusted correctly?

We tried adjusting the bypass valve that directs fluid between the two stages, but it didn't fix it.

 

[bigfrank]

I would put on a pressure gauge on the base of the cylinder to see if the second stage is kicking in. Sounds like the pump is not kicking down to low flow high pressure. Or just try a new pump. The unloading valve may be stuck. If pressure does not go above 1000 psi the pump is not kicking down. Some pumps are adjustable when it kicks down. Check the adjustment if it has it. If over adjusted it can't build enough pressure to kick down to the low stage.

I'm thinking something is wrong with the pump internally. Adjusting the pump pressure via the bypass valve that diverts fluid to the second stage didn't fix it. Even though the pump looked premium inside, there must be some tolerances that are off or something inside the pump.

 

[Deets066]

Good time to put a 28 gpm pump on.

 

[Junk Meister]

If your pump pressure checks out, look at your cylinder cups.

99.99% sure SS has pinpointed the problem
Went through this with my DAD I got to be right after all the Father-brothers vs. me Baloney
He finally had to ask me how to get it apart or I might never have known...

 

[AVB]

If the log splitter has an old L-head engine it can very well be just an engine valve clearance problem. I did one just a few months ago that would stall out the engine trying to split some Bradford Pear wood. Never killed the engine, just overloaded the due loss of hp by the engine not having enough compression due to valve leakage.

 

[Stump Shot]

99.99% sure SS has pinpointed the problem
Went through this with my DAD I got to be right after all the Father-brothers vs. me Baloney
He finally had to ask me how to get it apart or I might never have known...

Had this problem and after tearing the cylinder apart and putting new packing cups and seals in it was like a brand new splitter once again.

 

[Lightning Performance]

You need a pressure gauge on the ram feed line...like Doug said.

I bought a splitter about six years ago they thought had a bad single stage Vickers pump. They had the relief valve cranked down to eight hundred psi to stop stalling the ten horse Briggs motor. Turns out a replacement line coupler had about a 3/16" passage port. After drilling in out to 5/8" and putting the pump pressure back up to only 1200 it works great now.

Do make sure all the return ports are clear of debris and the return line is not collapsed internally. Brake hoses cause quite a night mare when they balloon up internally.

 

[Junk Meister]

When you are splitting a chunk of wood put the wedge into the chunk and watch it closely as you put the valve into hold/neutral /center position if you can see it spring back a very little smidgeon that is telling you that the cylinder is bypassing internally and the piston seals need to be replaced. What is happening is the pump never gets a chance to "Downshift"into the high pressure side due to the oil bypassing the seals and while you are in the cylinder don't forget to do the rod seals it is worth it. Hydraulic shops will hone or glaze break the cylinder/tube I tend to forget that part and just try to keep everything clean. Again I sincerely believe you have issues with the cylinder bypassing internally ...

 

[Al Smith]

Normally a bypassing cylinder will run hot .

 

[bigfrank]

Had this problem and after tearing the cylinder apart and putting new packing cups and seals in it was like a brand new splitter once again.

So do the packing cups leak or bypass fluid internally? Because this splitter doesn't have any leaks.

 

[bigfrank]

When you are splitting a chunk of wood put the wedge into the chunk and watch it closely as you put the valve into hold/neutral /center position if you can see it spring back a very little smidgeon that is telling you that the cylinder is bypassing internally and the piston seals need to be replaced. What is happening is the pump never gets a chance to "Downshift"into the high pressure side due to the oil bypassing the seals and while you are in the cylinder don't forget to do the rod seals it is worth it. Hydraulic shops will hone or glaze break the cylinder/tube I tend to forget that part and just try to keep everything clean. Again I sincerely believe you have issues with the cylinder bypassing internally ...

I'll pass this on to him so he can check it. Thanks.

 

[Stump Shot]

So do the packing cups leak or bypass fluid internally? Because this splitter doesn't have any leaks.

Yes, from one side to the other.

 

[Junk Meister]

So do the packing cups leak or bypass fluid internally? Because this splitter doesn't have any leaks.

Internal BYPASS try to READ the comments And in case you missed the part about replacing the rod seals --- Once they are disturbed they may not seal the same and start leaking..

 

[Al Smith]

Just for conversation one of my old D4 Cats,1943 2T series has bypassing cylinders .I've never had them apart but assume by the age have leather cup seals .That thing will heat those cylinder so hot you could fry an egg on them. That old it's most likely low pressure 14-1600 PSI .Large cylinders 5-6" .Damned thing is so slow you can change your mind three times before the blade moves .I've seen real good operators on these old things ,used to new equipment really get disgusted trying to grade with them .
.On that two stage pump it could have sucked some dirt,dust whatever into the pump and stuck the pump bypass valve which switches it to high pressure low volume .That valve should be set at around 900-1000 PSI . The relief valve in the main control valve is where the max system pressure is set on most splitters
If you can figure out what brand of pump it is more than likely an internet search will provide some troubleshooting information .You might try "Surplus Center" hydraulics which has some information available .

 

[Al Smith]

The only problem I've had was the detent return became stuck and would not hold in .I just took it apart and blew it out with compressed air .Most likely had a piece of sawdust or something stuck in it .My splitter has a return line filter not a suction side .