Lift Arms Creep Up when engine running

lwtm · Feb 12, 2013

I bought a 601 Workmaster that I found was missing the hydraulic piston housing assembly(Whoa!), but found a salvage and put it on. Now the lift works right except when there's no load (no equipment attached), the arms creep up anytime the engine is running. I can take my body weight and push them back down, but then they slowly creep back up again. Any suggestions of which valve or adjustment would cause this? Thanks.

JMOR · Feb 12, 2013

(quoted from post at 12:04:16 02/12/13) I bought a 601 Workmaster that I found was missing the hydraulic piston housing assembly(Whoa!), but found a salvage and put it on. Now the lift works right except when there's no load (no equipment attached), the arms creep up anytime the engine is running. I can take my body weight and push them back down, but then they slowly creep back up again. Any suggestions of which valve or adjustment would cause this? Thanks.

irst suspect would be Check Valve.

714_run · Feb 12, 2013

could make a linkage adjustment through side cover. linkage rod that hangs down below cyl. loosen jam nut shorten one turn

lwtm · Feb 12, 2013

Yeah, I was thinking of going through the side cover and hand pressing the linkages to get a response, before taking off the lift cover and checking valves. I don't have a clear plan so wanted to see what ya'll said b4 I started. Thanks!

JMOR · Feb 12, 2013

(quoted from post at 15:15:17 02/12/13) Yeah, I was thinking of going through the side cover and hand pressing the linkages to get a response, before taking off the lift cover and checking valves. I don't have a clear plan so wanted to see what ya'll said b4 I started. Thanks!

he reason that I suggested the check valve, is that it should not open & allow any flow to lift cylinder below 115PSI (equivalent to ~75 # lift force) and the back pressure valve sets steady state non-lift/hold pressure at ~40PSI (equiv to ~25# force), so a non-commanded lift condition should not see the minimal lift force that you have unless the check valve is leaking.
If the control valve is somehow commanding lift when you are not (with touch control lever), as with a mis-adjusted linkage, that should slam the unloader valve to full lift condition, thereby yielding ~1250 # lift force. Since unloader is not variable, but rather full open or full closed, I don't see the problem being in that area. Of course, there are still many other possibilities such as cracked housing, worn out leaky valves, etc.

Lift Arms Creep Up when engine running

lwtm

New User

JMOR

Well-known Member

714_run

Member

lwtm

New User

JMOR

Well-known Member

Similar threads