I need some help understanding a blown hydraulic filter seal on the new wood splitter

   #1  

CalG

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I traded in my old TW-1 splitter, that has served me well for many years, on a new TW-2.

I wanted the faster cycle time, and overall, the TW-2 machine is better built. It should be the last splitter I will ever need.

After bringing the splitter home, even though it was much too hot to work outdoors, I split cut rounds for about 45 minutes. I am well pleased with the increased productivity!

The next morning, after cutting a chainsaw tank full of rounds off the pile, I started splitting again. I noted that the detent enabled return stroke valve kick out was not releasing properly, and often bogging the engine. I never really let it go for very long, always doing the "manual over ride" to release the over pressure bypass in the valve and return to neutral. I thought about adjusting the spring detent to allow a "softer" reset to neutral, but considered that that the valve may just need a bit longer operation time to bed in. So I didn't change the adjusting bolt from the as new position.

Yesterday morning, after cutting another two fuel tanks full of rounds off the pile (an interesting unit of measure "rounds per tank full" ;-)
splitting began again. After I was in to the splitting for about 20 minutes, I was greeted with a shower of hydraulic fluid. In the 2 seconds to take in that the spray was coming from the area of the filter connection next to the valve, and though the fluid was messy and everywhere, it was not burning hot. I reached across the spray to shut down the Honda engine. I did take quite a shower in doing so. I can't imagine what I would have done if the fluid would have been hot.

On inspection after, it was easy to determine that the spin on filter seal had extruded out to cause the "return to tank" leakage. The spray occuring between the directional control valve and the filter IN, but at the spin on filter base seal ring.
Spinning off the filter, re-seating the flat seal, and reinstalling the filter, along with topping up the tank to replace the lost fluid, had everything back to operational. (with a good coating of "rust proofing and fire enhancement coating on the splitter and firewood respectively. ;-)

AND NOW THE PUNCH LINE

NOW, The return stroke kick out works perfectly!

What happened?

I'm puzzled.....
 
   #2  

dirttoys

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Wild guess, take no action based on my input on hydraulics:)

Cut the filter, see what it looks like. Crap in the fluid from break in, or just crap in the fluid. Maybe run new filter for 10-20 hours and cut it and look?

Best,

ed
 
  
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#3  
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CalG

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Wild guess, take no action based on my input on hydraulics:)

Cut the filter, see what it looks like. Crap in the fluid from break in, or just crap in the fluid. Maybe run new filter for 10-20 hours and cut it and look?

Best,

ed

You are speculating that:

The filter is offering sufficient reduction in flow to cause a back pressure enough to defeat the pressure sensitive release of the directional flow valve and cause the filter seal to be displaced.

That makes sense... i guess.
 
   #4  

dirttoys

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You are speculating that:

The filter is offering sufficient reduction in flow to cause a back pressure enough to defeat the pressure sensitive release of the directional flow valve and cause the filter seal to be displaced.

That makes sense... i guess.
Eh, that was phased well enough I re-read the post and you just reinstalled the filter, and it works. So... probably wasn't a plugged filter, or the remove reinstall cleared the objectionable situation?

Better guess (I hope) filter/gasket was poorly installed (crinkled gasket, loose filter) causing sub optimal performance?

Hope I was clear on my level of expertise with hydraulics:) My rudimentary understanding of detents; flow control valve that will hold while flow exists with relatively low pressure, then close with low/no flow and high pressure (deadhead). If the filter somehow allowed the valve to see flow or not 'feel' the high pressure of the deadhead. it would defeat the detent.

I honestly don't know if the filter, or filter bypass could do this, and if they could, what the exact circumstance would be, but, it was a fine effort to explain the symptoms, and the presumed cure:)

Best,

ed

hydraulic​

 
   #5  

Tinhack

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My guess is the filter wasn't turned the necessary 1/2 - 3/4 turn past contact when installed.
 
   #6  

triptester

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A return filter should never have pressure greater than 25 psi that would cause the filter to burst unless there is blockage. The common cause of blockage in a return filter is a damaged filter head by-pass valve. This valve is made of plastic and when it breaks it can obstruct the pipe to the reservoir causing excess pressure in the return line.
 
  
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CalG

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My guess is the filter wasn't turned the necessary 1/2 - 3/4 turn past contact when installed.
I agree and did reinstall the filter with tightness appropriate to my experience. I can't say what the condition was as received.

But that is not the question.

What was causing the return stroke kick out to malfunction?
What changed that now the kick out is working correctly?
 
   #8  

RickB

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I agree and did reinstall the filter with tightness appropriate to my experience. I can't say what the condition was as received.

But that is not the question.

What was causing the return stroke kick out to malfunction?
What changed that now the kick out is working correctly?
Post #6 could explain everything.
 
  
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CalG

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Post #6 could explain everything.
Post 6 mentions nothing of the return stroke kick out.

The filter did not burst, only the seal pushed out of it's groove. The spray of leaking fluid was NOT at system pressure, more consistent to a leaking garden hose washer. 25 psi seems about right.

The original filter was reinstalled. When I looked down the hole, I did not notice any displaced parts. I'll double check the reservoir inlet screen.
 
   #10  

dlctcg

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If this is a new TW-2.... Why not call Timber Wolf, they are an outstanding company & I'm sure will have ideas of what would have caused it & what the deal with the return detent issue is...

Heck even if it is not new I'd call them.... They helped me when we purchased a used TW-1P that was 8yrs old...
 
 
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