Combilift C4000:
Rear wheel not engaging forward motion

Please may I have some technical support as to why only the front wheels engage to forward and reverse motion but not the back wheel. I have replaced both proximity switches at the back wheel as well.
  • Posted 2 Feb 2023 10:39
  • Discussion started by Rickster
  • New Zealand
Showing items 1 - 5 of 5 results.
Hi Rickster

Did you get the truck working. Thanks skyreach and BLey for great direction.
  • Posted 10 Feb 2023 03:12
  • Reply by Richard_Irwin
  • Monaghan, Ireland
hi richard its not me having the issue its rickster in nz i only offered my opinion but in hindsight he did not state if it was a driive or turning problem that is why i stated that you would probably help
ps i do a lot of work on combilift in aus
  • Posted 4 Feb 2023 20:34
  • Reply by skyreach
  • Victoria, Australia
reach for the sky
Depends if your having a drive problem (wheels not driving/turning) or mode change problem (wheels not steering to side mode/forward mode) please be more clear.

If the truck is in side mode when you select forward mode and the front wheels turn from side mode to forward mode but not the rear wheel you possibly have an issue with your prox sensors on the Front wheels. Check to make sure front 0 degree prox sensor is lighting up and sending signal back to plc/relay. And that stop bolts are adjusted properly.

If your truck is in forward mode and the rear wheel turns to side mode but not the front wheels you have an issue either with the 90 degree prox on the rear wheel, stop bolt adjustment, 6port control relay, 6 port steering vlave or wiring. (Starting from most common to least)

If your having a drive problem where the front wheels turn forward and reverse but the rear wheel does not you may be into a brake problem (if the rear drive unit has a brake). If there is no brake remember these acr like an open diff if jacked up. Wheel with least resistance will turn. If no wheels will drive and you have checked all electrical you may have a bad drive unit.

Need more information if you want more help.
  • Posted 3 Feb 2023 23:30
  • Reply by BLey
  • Ontario, Canada
Hi. Skyreach,
Is the issue when you put the truck in sideways mode, the rear wheel starts to change to 90 but the front wheel do not.
If so, First thing to check is that the rear proxy is seeing the rear wheel turn to the 90. Check the stopper bolt is not limiting it, check that the rear proxy has read the plate (spacing around 8mm). If the rear proxy is reading the rear wheel turned to 90, then this signal is used to switch the change over valve, opening a solenoid that then allows the oil to the front right master cylinder which in turn also moves the left slave cylinder. This continues until the front left wheel 90 proxy reads the front plate and stops the sequence.

Hope this helps,
  • Posted 3 Feb 2023 20:55
  • Modified 4 Feb 2023 00:12 by poster
  • Reply by Richard_Irwin
  • Monaghan, Ireland
check the front proximity swiitches front left hand side wave a piece of metal in front of sensor be mindful that sometimes sensor can light up but can still be faulty also check the proximity wiring is not damaged if it is an earlier unit with relays you may have a faulty relay im sure that richard from combi lift can assist you
  • Posted 3 Feb 2023 20:29
  • Reply by skyreach
  • Victoria, Australia
reach for the sky

Having trouble using the Discussion Forums? Contact us for help.

Forkliftaction.com accepts no responsibility for forum content and requires forum participants to adhere to the rules. Click here for more information.

Oshkosh to acquire Spain’s Ausa Oshkosh, WI, United States

PREMIUM business

GemOne
Telematics for industrial fleets. Fleet & safety management solutions: track vehicles, boost efficiency, operate safer, & avoid unexpected downtime.
Global Industry News
edition #1179 - 16 May 2024
This week we bring news of big industry players expanding their companies with cross-border acquisitions and investments... Continue reading
Fact of the week
In a room of just 23 people, there is a 50/50 chance that at least two people have the same birthday. In a room of 75 people, there's a 99.9% chance of at least two people matching.
Latest job alerts …
Maryville, Tennessee, United States
Cincinnati, OH, United States
Louisville, Mississippi, United States
Columbus, OH, United States
Upcoming industry events …
May 30-31, 2024 - Singapore, Singapore
June 11 - 13, 2024 - Rotterdam, Netherlands
October 23-25, 2024 - Ningbo, China
Upcoming in the editorial calendar
DIGITISED STOCK CONTROL AND FORKLIFTS
May 2024
PRODUCTION OF MATERIALS HANDLING EQUIPMENT IN NORTH AMERICA
Aug 2024

PREMIUM business

Lift Tek Elecar
Global leader in the design and manufacture of masts, carriages, integral sideshifters & fork positioners.
Global Industry News
edition #1179 - 16 May 2024
This week we bring news of big industry players expanding their companies with cross-border acquisitions and investments... Continue reading
Upcoming in the editorial calendar
DIGITISED STOCK CONTROL AND FORKLIFTS
May 2024
PRODUCTION OF MATERIALS HANDLING EQUIPMENT IN NORTH AMERICA
Aug 2024