Elect. Hydraulic pump help

[rskybiz]

Went to dump my load of chips this afternoon and it lifted but would not hold as normal. Any clues where I should start? Not sure of how exactly the the solenoid works bit feel like that is where I'm headed.

 

[sawinredneck]

Something in the system is letting the pressure bypass somewhere! The cylinder may be leaking, or one of the control valves is sticking open? Try lightly tapping on them, spray them down with some PB blaster, etc, and see if they break loose.
The solenoids just use an electromagnetic force to move the spool valve back and forth. Quite simple once you get into one.

 

[rskybiz]

Electrical all checks out, no leaks in cyl. That are apparent. I'll try the pb and some light taps.
Must be check valve in there some where as well. Would that be in or under the pole where the electro switch is?

 

[sawinredneck]

No, what happens is the valve locks and hold the pressure, then when you go to let it down it moves to release the pressure from the cylinder to let the bed come down. Here's a pic, it might help more than my description.



When the solenoid gets power, it moves the spool exposing the two closed ports, then when power is lost it goes back to the closed position. Depending on how your system is plumbed, it may be stuck open or closed. The spring may have broken, the solenoid died or it just got gummed up and stuck one way or the other!

 

[BlackSmith]

Check for signs of Teflon tape being used anywhere on the fittings. Big no no and a big problem for solenoids and such. Ya never know if Bubba has worked on it or not.

 

[lumberjack]

Yeah it's likely going to be the solenoid.

A cylinder with a good seal in the gland and work ports (valves aren't leaking) can't collapse due to a piston seal leaking, unless something blows.

 

[rskybiz]

Pulled it spring is broke, Napa to the rescue in the am I hope.
Thanks a bunch for the picture I tried a bunch of searches but none as cleanly pictured as that came up. What did you use for a keyword? Or was that just something you had.

 

[sawinredneck]

Electric Hydraulic solenoid.

Glad you got it sorted out!