Discussion:
Clark CMP18 is not engaging forward

Hi guys. Problem with a brand new Clark CMP18. The truck is not engaging forward after about only 20 hours of work. All switches are OK. So I guess problem is not electric. What else should I check if it's a new truck?
Any help will be appreciated.
  • Posted 17 Sep 2011 08:29
  • By ob1kenobi
  • joined 22 Nov'10 - 153 messages
  • SAN P.SULA, Honduras
Cheers!
Showing items 1 - 16 of 16 results.
Gracias Juan Carlos. En este momento estamos enfocados en modificar el sistema de escape lo cual esta haciendo que el equipo recaliente. Una ves resuelto esto, pasaremos a revisar el problema de la transmision. Haremos las revisiones de presion, tal y como tu nos lo sugieres.
Slds
OB1
  • Posted 24 Sep 2011 01:50
  • By ob1kenobi
  • joined 22 Nov'10 - 153 messages
  • SAN P.SULA, Honduras
ob1kenobi:
Te sugiero que cheques las presiones de la transmision primero estando fria y despues checarlas cuando esta caliente.
Asi te podras dar cuenta si tiene o no un problema con los sellos de la transmision o esta fallando la bomba.
saludos.
Juan Carlos Pastrana M
  • Posted 23 Sep 2011 01:51
  • By pastrana_j
  • joined 3 Aug'10 - 103 messages
  • Puebla, Mexico
Yes, reverse was working.
  • Posted 23 Sep 2011 01:20
  • By ob1kenobi
  • joined 22 Nov'10 - 153 messages
  • SAN P.SULA, Honduras
The baffling part is that you only loose forward when the truck heats up. I am assuming that reverse works fine. It that correct?
  • Posted 21 Sep 2011 11:07
  • By rogeriwt
  • joined 10 Apr'07 - 323 messages
  • Massachusetts, United States
The truck works fine when it cools down.
  • Posted 20 Sep 2011 09:59
  • By ob1kenobi
  • joined 22 Nov'10 - 153 messages
  • SAN P.SULA, Honduras
What happens if you swap the coils around and make forward on the lever reverse on the truck? DO you still have the same problem?
  • Posted 20 Sep 2011 08:13
  • By rogeriwt
  • joined 10 Apr'07 - 323 messages
  • Massachusetts, United States
joe_d
Everything in the transmission is OK. We have confirmed that the problem is due to overheating. When the truck cools down, transmission works fine. The exhaust tube that goes to the muffler passes to close to the part of the radiator where the trans. oil cooler is located. Actually it is the transmission oil that heats up so much that it is overheating the truck's coolant. Have complained to Clark and they only respond to me that they've never seen this problem!
Thanks for the Royal Purple tip. I'll try this coolant on this truck after I modify what I can of the exhaust pipes.
Cheers!
  • Posted 20 Sep 2011 07:05
  • By ob1kenobi
  • joined 22 Nov'10 - 153 messages
  • SAN P.SULA, Honduras
Cheers!
Try swapping the 2 coils and spools around and see if your problem changes direction. Don't forget there are also 2 diodes per valve in the wiring harness.

As for the heating problem, we had overheating problems (one of the operators wearing shorts actually singed the hair off the back of his legs on the hood) on 2 new Clark CQ25s. The fix was to add Royal Purple's Purple Ice additive to the coolant. It cut the operating temps in half.
  • Posted 20 Sep 2011 03:08
  • By joe_d
  • joined 25 May'10 - 253 messages
  • Texas, United States
Ain't nothing I can't fix but a broken heart and the break of day!
Let us check on that.
Thanks

OB1
  • Posted 20 Sep 2011 01:21
  • By ob1kenobi
  • joined 22 Nov'10 - 153 messages
  • SAN P.SULA, Honduras
Maybe the spool on the transmission that the coil is attached to is binding or something if coil is energizing then possibly spool itself is not being operated properly
  • Posted 19 Sep 2011 09:32
  • By kevin_t
  • joined 2 Dec'10 - 1,301 messages
  • Pennsylvania, United States
No i would NOT remove the thermostat,maybe good idea to install a new one but NEVER remove it completely.
  • Posted 19 Sep 2011 09:29
  • By kevin_t
  • joined 2 Dec'10 - 1,301 messages
  • Pennsylvania, United States
It seems to me that no matter how hot things get the transmission should still engage. Something other than heat is causing a problem.
  • Posted 18 Sep 2011 00:48
  • By mrfixit
  • joined 11 Dec'08 - 1,434 messages
  • New York, United States
Kevin:
Everything is AOK. The problem seems to be the way the muffler circuit heats the radiator, adding to the harsh conditions were the truck is working. There's a Cat P3500 working right beside this one, with no overheating problem at all. We'll try to insulate the muffler and pipes to see if heat transfer is reduced. Still would like to know if there is anything else can be done. Can we omit the temp thermostat altogether?
  • Posted 18 Sep 2011 00:39
  • By ob1kenobi
  • joined 22 Nov'10 - 153 messages
  • SAN P.SULA, Honduras
Fan belt tight? How about coolant level in the radiator? Fluid level in the trans ok? Trans cooler have anything blocking air flow?
  • Posted 17 Sep 2011 09:45
  • By kevin_t
  • joined 2 Dec'10 - 1,301 messages
  • Pennsylvania, United States
Yes, the solenoid is being energized. Just found out that the truck has been overheating and that when it cools down, the transmission does engage forward. We've been looking at the arrangement of the radiator and muffler on this truck and it seems that the muffler is too close to the radiator, provoking overheating of the coolant, especially in this tropical climate and a textile mill application.
Again I want to ask for any suggestions on how to solve what now seems to be an overheating issue.

Thanks,

ob_1
  • Posted 17 Sep 2011 09:18
  • By ob1kenobi
  • joined 22 Nov'10 - 153 messages
  • SAN P.SULA, Honduras
Cheers!
Is the Solenoid on the transmission being energized when in FWD? Should be a coil for fwd and one for rev.. Can check by holding a screwdriver to the end of the shaft the coil is on and put in fwd should feel the magnetic pull of the coil on the screwdriver
  • Posted 17 Sep 2011 08:58
  • Modified 17 Sep 2011 08:59 by poster
  • By kevin_t
  • joined 2 Dec'10 - 1,301 messages
  • Pennsylvania, United States

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