Discussion:
Boom gets STUCK and will not go DOWN then DROPS

Please Help!
I have a Toyota 7 series diesel forklift.
Problem:
Unloaded, the boom goes up and down without any problem.
Loaded, the boom sometimes gets STUCK UP, and does not go down.
- when try to lower it, the chains fold down but the boom stays. Then maybe because of gravity, the boom suddenly drops until the chains become straight. very dangerous..
- handling heavy objects, it sometimes works. i pressume gravity forces the boom to go down? it gets stuck more handling lighter objects..

Nothing is blocking the way of the mast.
I topped up on the hydraulic oil.
No visible leaks of hydraulic oil.
The load that I handle is not exceeding the capacity of the forklift.
No indicators on the panel lights up.

Thanks in advance..
  • Posted 21 Jul 2015 14:06
  • Modified 21 Jul 2015 14:09 by poster
  • By vincent_v
  • joined 21 Jul'15 - 3 messages
  • Manila, Philippines
Showing items 1 - 5 of 5 results.
Can you please share any resolution that you had with this problem of the mast getting stuck?
  • Posted 11 Jan 2022 11:44
  • By Roman_Beyer
  • joined 11 Jan'22 - 1 message
  • California, United States
RRB
I definitely would check the roller bearings. Is there a lot of slop in the carriage? Also, are the freelift chains worn? Most diesel lifts are in lumber/brick yards and are notorious for running around with worn chains.
  • Posted 25 Jul 2015 09:30
  • By Hero5
  • joined 17 May'14 - 56 messages
  • South Carolina, United States
I would check the fork carriage roller bearings.
  • Posted 23 Jul 2015 20:25
  • By mrfixit
  • joined 11 Dec'08 - 1,434 messages
  • New York, United States
the mast is 4meters and it would hang up at around 2meters.
*without load, it has no problems.

my observations/guesses are:
-control valves should be working fine, because without load the mast goes up and down with no problems.
-hydrualic oil if full, no leaks.
-loaded, mast can go up and down around the 1meter height, but higher, around 2meters it would get stuck (or it will slowly shake going down as if it is misaligned). i havent tried it loaded going up and down from the peak.
*would the mast bearings have anything to do with the problem? or is there another cause you can think of?

thanks!
  • Posted 23 Jul 2015 15:17
  • By vincent_v
  • joined 21 Jul'15 - 3 messages
  • Manila, Philippines
How about the mast channels hanging? Where does it hang up? How high woulld you say? Could need grease along the rails and the rollers in the mast or could need to be reshimmed entirely.
  • Posted 23 Jul 2015 11:15
  • By Hero5
  • joined 17 May'14 - 56 messages
  • South Carolina, United States

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