Clark TW40:
Forklift jumps then dies?

We have a TW40 3 wheel forklift and it devloped an issue where it jumps and then nothing. It will basically move 2 feet on the motor jump then its dead. If you try to creap it in does nothing until you are far enough in to engage the motor which dies instantly. You can still shift if forward and reverse the reverse beeper comes on. TO get it to jump another few feet you have to put it in nuetral and cycle the key on and off. We are guess it is the throttle but I am not sure what to test or check 1st. Any suggestions would be greatly appreciated.
  • Posted 16 Aug 2012 06:19
  • Discussion started by specequip
  • Michigan, United States
Showing items 61 - 75 of 94 results.
I just replaced the bad #2 and it does the exact same thing. I do not hear it speeding up at all. It seems like it has 2 speeds creep and then jump. Well that was $350 down the tubes. I did pull the board out of the ev1 and it has some corrosion on it. Maybe the ev1 is bad? Is there any way to test the board?
  • Posted 21 Aug 2012 06:47
  • Reply by specequip
  • Michigan, United States
IF this is an ev1 system
as soon as you depress the accelerator pedal and the directional contactor comes in you should hear an audible hum comming from the control panel.
As you push the pedal down further that hum will speed up
Are you hearing this?
If not then you are on the right track with an scr issue.

Also if you are having to push the pedal down further to get any reaction out of the system it may be that you are pushing it down to the point that it hits the 1A switch in the accelerator box and this is why it is jumping 2ft....
WHEN this happens if it tries to go into 1A speed and if there is a problem in the SCR range the PMT will see this and trip the truck out.
This is why you have to shut the truck down and start it back up. Cycling the key resets the PMT circuit.

Being that you said you checked the scr's and found some problems with a couple of them that is more than likely the issue.

Get the parts and install them and see what happens :o)
  • Posted 18 Aug 2012 08:36
  • Reply by Jplayer
  • North Carolina, United States
John Player Jr
_________________
LiftOne, LLC
Charlotte, NC
Email: jplayer@liftone.net
Thanks everyone parts are on order. Actually order off ebay!
  • Posted 18 Aug 2012 07:06
  • Reply by specequip
  • Michigan, United States
You need to use their industrial site, which is for the material handling industry.
www dot fsip dot biz

Under the support tab on the left hand side of the page you will find a tab for technical manuals.
  • Posted 18 Aug 2012 02:16
  • Reply by Partsguy5
  • California, United States
call me stupid but I cannot figure out where on www dot flightsystems dot com website to look. can you possible post a link or email? spectorequipment at spectorequipment dot com
  • Posted 18 Aug 2012 00:31
  • Modified 18 Aug 2012 00:32 by poster
  • Reply by specequip
  • Michigan, United States
specequip;
You will find a list of the various equipment mfr. that used the same GE controllers along with their part numbers in the download from Flight Sys.
  • Posted 18 Aug 2012 00:15
  • Reply by MEngr
  • Missouri, United States
Is there any place that would have these GE rectifiers in stock. Noone around me has it and clark dealer is 2-3 days out.
  • Posted 17 Aug 2012 23:54
  • Reply by specequip
  • Michigan, United States
specequip;
Go to the Flight System web site and download the service manual for the GE controller. You will find additional information with regards to the control system you have. Along with the technical advise you have been getting you should have your truck's problems addressed.
  • Posted 17 Aug 2012 08:43
  • Reply by MEngr
  • Missouri, United States
Dol you have a email to post in your profile,have to post as mine is as site strips out readable address's
  • Posted 17 Aug 2012 07:53
  • Reply by kevin_t
  • Pennsylvania, United States
Yes that is #5 and a bad #5 could cause the same symptom.
  • Posted 17 Aug 2012 07:48
  • Reply by mrfixit
  • New York, United States
Figures I have a 998517 or 259A2135G1 coming in the mail. That is the number my local clark dealer gave me. I am hoping that is #5.
  • Posted 17 Aug 2012 07:42
  • Reply by specequip
  • Michigan, United States
Ok, that is a symptom of bad #2. Clark # 998518
  • Posted 17 Aug 2012 07:39
  • Reply by mrfixit
  • New York, United States
GE 259A2138G1 That is the bad rectifier. I just pulled it
  • Posted 17 Aug 2012 07:15
  • Reply by specequip
  • Michigan, United States
ok,sorry i was under the impression this truck had a ev100 system in it,i dont have any part numbers for the 2 and 5 rec for an ev1.
  • Posted 17 Aug 2012 06:29
  • Reply by kevin_t
  • Pennsylvania, United States
OK. Basically. to get the truck to respond. You have to have it in neutral then turn on the key. put it in forward or reverse. It basically jumps then dies. If you try to creep it you can hear the motor try to move but it does nothing until it jumps and dies. If you jack up the front tires with no load and slowly push the pedal it starts to spin and low and high kick in fine. Sometimes it stops working this way and you have to reset it. SCR2 tested bad on his handyman tester. It shows open.
  • Posted 17 Aug 2012 05:20
  • Reply by specequip
  • Michigan, United States

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Fact of the week
A 1904 lecture by scientist Elie Metchnikoff extolled the benefits of consuming yoghurt for halting the "intestinal putrefaction" which he believed causes aging. The press reported yoghurt as a cure for aging and the ensuing popularity is still with us today.