Discussion:
Old Clark EC40E Drive Related Issues

Hello, I am new to this forum, but figured this was the right place to ask questions about older forklift issues. We just recently purchased an old Clark EC40E forklift and all of the functions work accordingly..Except reverse. Forwards always works without a hiccup, however, sometimes in reverse it will lurch backwards and pop the breaker on the dash. I know the points are making contact because I can hear them make contact before I start to drive in forwards or reverse. If I am driving forwards and put it in reverse while still barely rolling it doesn't do this, but from a dead stop under light application of the throttle, it does it almost every time.. very intermittent. I was wondering could anyone point me in the correct direction as to where to look or what commonly goes wrong with these machines. We had a local forklift repair shop come out and look at it and the guy had never even seen one of these machines before (never a good sign) and didn't have a clue what was wrong with it.

Thank you in advance.

Billy
  • Posted 19 Jun 2018 02:20
  • By billy_g
  • joined 19 Jun'18 - 5 messages
  • Montana, United States
Showing items 1 - 10 of 10 results.
I do have an old C500EC40E wiring diagram which shows an optional fault detector reset switch. When a fault is detected the switch trips and opens the circuit to the key switch. This is likely what that switch is. An option
would be to return the circuit to original.
As far as diagnosing faults go, first start with the battery, make sure is fully charged and no corrosion. Controllers can fault out from corroded or dirty batteries due to negative voltage.
  • Posted 22 Jun 2018 10:47
  • By tom_p
  • joined 21 Feb'11 - 198 messages
  • Alberta, Canada
Sounds good, I will do those tests once my dad gets back home from camping. He understands that stuff much better than me.

Thank you,

Billy
  • Posted 22 Jun 2018 06:26
  • By billy_g
  • joined 19 Jun'18 - 5 messages
  • Montana, United States
Hmm.. I am not sure? I believe it is wired from the key though. If the breaker trips I can still perform lift functions also. Should I maybe get rid of the breaker??

Thank you,

Billy
  • Posted 22 Jun 2018 06:24
  • By billy_g
  • joined 19 Jun'18 - 5 messages
  • Montana, United States
the wiring diagram shows no original dash circuit breaker on your unit. Is the breaker wired into the control circuit? Maybe direct from key switch?
  • Posted 21 Jun 2018 23:57
  • By tom_p
  • joined 21 Feb'11 - 198 messages
  • Alberta, Canada
Your best bet is to run a current test on the truck to see what you are pulling for amps. Are you sure you have a good battery? Test the voltage on the battery cables while under load and see what the voltage drop is.
  • Posted 21 Jun 2018 22:18
  • By BREWSKI
  • joined 10 Jan'12 - 1,699 messages
  • Nebraska, United States
The model number is EC40E and Serial is EC40ESG 1572-2137.

Thank you,

Billy
  • Posted 21 Jun 2018 04:18
  • By billy_g
  • joined 19 Jun'18 - 5 messages
  • Montana, United States
The model number is EC40E and Serial is EC40ESG 1572-2137. I appreciate your help. Also today the "breaker" tripped a few times while driving forwards and lifting a load at the same time. Seems to trip more easily if I am performing a lift function. Are the brushes fairly easy to access? Do I have to remove the battery to access the drive motor?

Billy
  • Posted 21 Jun 2018 04:18
  • By billy_g
  • joined 19 Jun'18 - 5 messages
  • Montana, United States
Do you have a serial number? This will help identify what your problem might be.
  • Posted 20 Jun 2018 22:50
  • By BREWSKI
  • joined 10 Jan'12 - 1,699 messages
  • Nebraska, United States
Inspect your drive motor commutator and brushes. Burnt commutators or brushes worn down too much that can also cause intermittent traction loss.
  • Posted 20 Jun 2018 02:45
  • By tom_p
  • joined 21 Feb'11 - 198 messages
  • Alberta, Canada
Confirm you battery, cabling and related buss bars are OK and tight.
Your symptom can occur if a back up alarm has been connected to the reverse circuit incorrectly.
Check the brake pedal wiring/switches and return spring, when reversing sometimes the pedal will move cutting out reverse traction.
I do not recall a dash circuit breaker on those old electrics. Unless it was installed to resolve some electrical short. Send to my profile the full model and serial number. May have some old wiring diagrams for your unit.
  • Posted 20 Jun 2018 02:42
  • By tom_p
  • joined 21 Feb'11 - 198 messages
  • Alberta, Canada

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