Discussion:
Mast drift and hydraulic schematic

Hi all.
I have a GP25K with a mast drift (lowering) issue.
It happens in all stages of lift. I repacked the secondary cylinders a year ago. This issue came on suddenly in the last week.
I'm suspecting a load holding valve issue, and I have the parts breakdown for the HCV but they don't list a holding valve in the diagram. Anyone have a hydraulic schematic for this unit they can share?
Thanks.
  • Posted 8 May 2019 00:09
  • By Scrid
  • joined 30 Apr'12 - 40 messages
  • Nebraska, United States
Showing items 1 - 2 of 2 results.
Hi Swoop,
Its a Cat GP25K / AT17C90291
I didn't get the mast number but the HCV is a 3way.
I think each section has its own load holding valve.
Parts manual calls it a "poppet". I'll probably have to split the lift section out and inspect the poppet and seat for damage / debris, or a broken spring.
  • Posted 9 May 2019 03:44
  • Modified 9 May 2019 03:44 by poster
  • By Scrid
  • joined 30 Apr'12 - 40 messages
  • Nebraska, United States
whats the truck serial number?
and a mast number, (look on the right hand side about half way down or just under the tilt cylinder yoke mount) it should be stamped there.
  • Posted 8 May 2019 11:31
  • Modified 8 May 2019 11:31 by poster
  • By swoop223
  • joined 23 Mar'12 - 3,691 messages
  • North Carolina, United States
You've been swooped!
swoop223@gmail.com

Post your Reply

Forkliftaction accepts no responsibility for forum content and requires forum participants to adhere to our rules of conduct. Click here for more information.

If you are having trouble using the Discussion Forums, please contact us for help.

Yale GDP100M
Flesherton, Ontario, Canada
Used - Sale
Toyota 8FG25
Braeside, Melbourne, Victoria, Australia
Hire

PREMIUM business

Hangzhou Manforce Material Handling Equipment Co., Ltd
Specializing in Nichi and conventional forklift products, we create significant value for all our partners!
Upcoming in the editorial calendar
WIRELESS CHARGING
Aug 2025
MANAGING MIXED FLEETS
Oct 2025