How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Matthias Your Own Question
Matthias, Technician
Category: Heavy Equipment
Satisfied Customers: 114
Experience:  10+ Yrs experience in Heavy Duty / Automotive / John Deere,New Holland and Case IH, Cummins and Cat
Type Your Heavy Equipment Question Here...
Matthias is online now
A new question is answered every 9 seconds

Hiab 125-2, Crane creeps slowly down on main ram, falling speed

This answer was rated:

Hiab 125-2, Crane creeps slowly down on main ram, falling speed has increased over the last year
Hello there

There could be different things wrong.

1st the piston seals are leaking and the oil is bypassing the cylinder

2nd there should be a 'load check' block in the system that controls the ram. it is usually mounted to the cylinder or very close to it. If this valve bypasses the ram will creep.

to find out what the problem is, lower the main ram completely, disconnect the hose or line on the side that would extend the ram, cover the hose. Have some one run the hydraulics and move the lever 'boom down' if there is any oil comming out of the cylinder, the piston is bypassing and will need to get resealed.

If there is no oil, the load check valve is leaking internally. these are usually not serviceable and will need to get replaced

If you have any more questions, i will be here to answer them


Matthias and 3 other Heavy Equipment Specialists are ready to help you
Customer: replied 8 years ago.

Hi Matthias,

I will try your suggestion tomorrow, should you want feed back on the result let me know, should it be the load check valve I note that there are seals on this unit, I am tempted to break the seals and try new settings or take it to bits and have a look!


<p>Jed,</p><p> </p><p>Thanks for accepting my answer, i would like to know what you find</p><p> </p><p>Matt</p>