Hydraulic flow issue

254kingtractor · Sep 24, 2015

Hello members hoping someone can help, I have a 26HP tractor nothing big but I use it quite often, I just added a Thumb Grapple and I am teeing off the main pressure side of the hydraulic system, when I do this bucket and grapple work great but I知 losing my power steering, if I change configuration to get power steering back the grapple doesn稚 work, the only think I haven稚 tried is a restrictor, if anyone has had this problem would love some help, thank you for your time.

/pine · Sep 24, 2015

Are you familiar with both open and closed systems?
In closed center systems (typical of most smaller tractors) you cannot "T" a pressure line...(because the fluid will be diverted) valves must be in a series...

You mentioned a grapple so I assume there is a loader...?...if so see if there is a PB (Power Beyond) port on the loader valve...

On closed center systems only return lines can be Teed together...

kennyd · Sep 25, 2015

/pine said:
Are you familiar with both open and closed systems?
In closed center systems (typical of most smaller tractors) you cannot "T" a pressure line...(because the fluid will be diverted) valves must be in a series...

You mentioned a grapple so I assume there is a loader...?...if so see if there is a PB (Power Beyond) port on the loader valve...

On closed center systems only return lines can be Teed together...

You are almost correct, but I think you meant OPEN center systems as that's what most tractors use.

To the OP: You cannot Tee into the high pressure lines, all valves MUST be added in series. When you Tee into lines that puts the valves in parallel and hydraulic fluid (like electricity) will take the path of least resistance, and the will be the other valve not being asked to do any work.

J_J · Sep 25, 2015

/pine said:
Are you familiar with both open and closed systems?
In closed center systems (typical of most smaller tractors) you cannot "T" a pressure line...(because the fluid will be diverted) valves must be in a series...

You mentioned a grapple so I assume there is a loader...?...if so see if there is a PB (Power Beyond) port on the loader valve...

On closed center systems only return lines can be Teed together...

You have the principle of operation reversed.

Closed center valves are all in parallel, and can be teed together.

Open center valves are in series.

The supply of closed center valve goes to each closed center valve and has pressure at the input.

Open center valves have no pressure at the input to the valve. The pump fluid passes through all valves to tank until a cyl is activated.

If you tee into an open center line, you now have two paths and the fluid will go to the path of least resistance.

If the steering circuit is hyd operated, it usually has a separate circuit, as the steering is a safety thing, and must have priority.

254kingtractor · Sep 25, 2015

254kingtractor said:
Hello members hoping someone can help, I have a 26HP tractor nothing big but I use it quite often, I just added a Thumb Grapple and I am teeing off the main pressure side of the hydraulic system, when I do this bucket and grapple work great but I知 losing my power steering, if I change configuration to get power steering back the grapple doesn稚 work, the only think I haven稚 tried is a restrictor, if anyone has had this problem would love some help, thank you for your time.

THANK YOU FOR THE HELP, ILL KEEP YOU POSTED AND YES THERE IS A FEL