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HC HC is offline
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Default Hydraulic cylinder/valve problem, help please.

On Aug 6, 1:47 am, Tom wrote:
HC wrote:
Hello, all.


Here's what I have:


- 8 HP Briggs & Stratton IC engine
- Haldex/Barnes 16 GPM direct drive hydraulic pump
- Prince "Logsplitter" vavlve (like can be seen he
http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_47..."
- 4 inch bore, 30 inch stroke cylinder
- 3.5 inch bore, 36 inch stroke cylinder


What works:
The engine, hydraulic pump, valve, and 4x30 cylinder are used as a log
splitter. Work great. No problems.


What does't work:
I disconnected the 4x30 cylinder and connected a 3.5 x 36 bore
cylinder for another project (with about 10 feet of hydraulic hose I
can use the logsplitter as a power supply for other hydraulic
projects, which is what I'm doing). Whereas on the logsplitter ram-
speed is not a concern, my current project is sensitive to ram speed.
When I move the handle of the spool slightly to move the ram at low
speed the ram moves very slowly, no problem, until it hits the load
and then the engine bogs and dies. However, when I move the handle to
full-open against the load the ram moves just fine, but way too fast
for my needs and control.


The problem is that I need to be able to control the speed of the
hydraulic ram in my current project but when I try to move the handle
of the vavle slightly, to move the ram slowly, it bogs the engine and
will kill it, under load.


It's got to be the valve or the pump, but I don't know enough about
these things to be sure which it is. I would guess the valve is the
problem, maybe restricting the fluid too much on partial
engagement....but I don't really understand the inner workings of
these things well enough to even form a theory.


Any help would be appreciated.


Thank you.


--HC


Log splitter valves are cheap n nasty and have no real need to
be able to feathered, ie used to choke the flow.
A solution and quite cheap, would be a Prince adjustable
flow control valve in your system:http://tinyurl.com/23btm3

Tom- Hide quoted text -

- Show quoted text -


Thank you Tom for your reply, that might be the trick. After several
readings I'm going to attempt to adjust the bypass valve and see if
that makes a difference. I doubt it will since the engine doesn't die
when I have it against the end of the hydraulic cylinder travel, fully
stopped but with the valve fully open so the bypass must be working.
but it's a quick and cheap attempt to fix the problem. I have a
pressure gauge on the system so I can see where I set it. The
frustrating part is that, and I need to verify this, the pressure was
only a few hundred pounds when the valve was barely open and it was
killing the engine. Who knows. I need to verify my data by doing it
again and paying more attention.

Thank you for your suggestion.

--HC