My old (1971) Clark EC500 has developed a new issue. After changing out the hydraulic motor and pump for the mast, the forklift no longer moves very fast. Battery voltage is up and everything works normal until you touch the accelerator. You can only touch it very lightly and as you do you can watch the voltage drop to the red zone in a few seconds. You can hear the motor spin up and it moves forward very slowly. The same happens in reverse. Stepping on it even more and it just stops. I'm thinking the potentiometer is shot but I have no idea why it would suddenly go.
Showing items 1 - 11 of 11 results.
Awesome! Glad you got it sir !
Sorted out. The cables coming from the battery connector into the fork lift reverse themselves going through the channel in the body. Since they had their ends replaced at some point in time there was no markings on them and I got them backwards when I hooked them up to the motor. I should have double checked with an ohm meter when I was putting it back together. All good now.
I will double check everything tomorrow.
Reverse isn't the issue , I'm concerned about cable on wrong post ie a negative cable hooked up on wrong post can you trace the cables on post that has two on it just to eliminate a cable hooked to wrong post a lot of the older units had a main negative that was fed from pump motor meanwhile I while see if I can find a diagram
I wondered that myself. I have one cable on the front terminal and two on the rear. The mast wouldn't go up if I got them reversed, so I think I'm ok there. I didn't disconnect anything else other than the main battery plug.
Have you checked the cables to pump motor ?
Does one terminal have two cables and other just one ? Also did you move or unplug any wires as you replaced the motor ? It sounds like you may have a misplaced cable or wire
I will resend info
Thanks for the list. Unfortunately the file is too small and I can't read it. Could you post it again? I tested all my batteries and everything is good there. the mast goes up without a problem and the side shift works as well. It's only the movement of the truck itself. Which is weird because I didn't touch anything related to that circuit when I swapped out the pump motor.
That unit I believe has an ev-1 control
I have sent a diagnostic flow chart
You can use for diagnosis
First check for voltage drop on battery by placing positive lead of meter in positive cable and negative lead in negative cable
Then try to move snd watch for voltage drop on battery it should not drop more than 1-2 volts
What is serial number ? If voltage drops that's an indication of low/ dead battery. Will the hyds work ? First thing is take a meter put positive lead probe into positive battery cable
Then put negative lead probe in negative cable then try to move and watch meter if it drops then you have low charge or bad battery cells
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