Clark EC500:
EV-1 no scr hum

Ok, I've been working on an old Clark M: EC500-120 SN: E912-0008-6380. Unit has an Ev1 with extra large #1REC, #5REC etc. When you travel the contactors pull in but No scr hum and no travel. I have removed and tested the #1,#2,#5 RECs with a 12 volt battery and they will switch on and remain on until circuit is opened. I think they are good. I've tested #3,4 RECs (diodes) with a fluke meter and they conduct in one direction only. Resistance test are showing 750k ohms from componets to chassis. Isolated Battery by lifting and placing a sheet of plywood between battery and chassis Becouse I've heard of chassis voltages and some strange affects they can have. Have tested and inspected current sensor and all conections are good. Have raised drive tires put directional switch into fwd so fwd contactors close and then manually closed 1A contactor-drive wheels turn with 1A closed which tells me brushes etc. are good. Tested all Caps -good.
One thing that I have noticed is there is no cable or wire on T2.
Thanks ahead for any help anyone can give me.
  • Posted 7 Aug 2010 07:33
  • Discussion started by rrlift
  • Illinois, United States
Working so I can ride.

Post your Reply

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

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

Toyota 8FBE20U
Flesherton, Ontario, Canada
Used - Sale
Terberg YT223
Balling, Denmark
Used - Sale
Latest job alerts …
Jefferson, WI, United States
St. Louis, MO, United States
Johnston, IA, United States
Fact of the week
The Michelin Guide with its star rating system originated in France in 1900. The guide was created as a marketing tool to encourage more car travel and consequently increase the demand for tyres. It initially contained maps, tire repair instructions, and lists of restaurants, hotels, and mechanics.
Global Industry News
edition #1234 - 12 June 2025
As a journalist focussed on the materials handling sector, it is difficult not to notice the regularity of news stories that detail injuries to – or worse still the deaths of – forklift operators... Continue reading
Fact of the week
The Michelin Guide with its star rating system originated in France in 1900. The guide was created as a marketing tool to encourage more car travel and consequently increase the demand for tyres. It initially contained maps, tire repair instructions, and lists of restaurants, hotels, and mechanics.
Upcoming industry events …
June 17-19, 2025 - Rotterdam, Netherlands
August 29, 2025 - Boksburg, South Africa
October 15-17, 2025 - Singapore, Singapore
Global Industry News
edition #1234 - 12 June 2025
As a journalist focussed on the materials handling sector, it is difficult not to notice the regularity of news stories that detail injuries to – or worse still the deaths of – forklift operators... Continue reading