M4900 throttle spring

   / M4900 throttle spring #1  

gadgetman

Member
Joined
Jul 4, 2003
Messages
32
Location
Richland, Georgia
Tractor
Kubota M4900
Where (or is there) a pull-back spring on the M4900 throttle linkage? My M4900 has both the lever and the pedal on the floor-board.

Lately, it won't idle back lower that about 1500 RPM. You can reach over and pull up on the foot pedal and it will idle down. I figured that the idle spring had slipped off or there was a bind in the linkage. Linkage appears OK (not rubbing on anything). I applied a little WD-40 to the joints to see if that was the problem. Never did find a spring or anything that would return it to idle.

Any help!!!!
 
   / M4900 throttle spring #2  
I looked in the service manual and cannot find a spring either. Will check setting idle speed and get back to yoy. /forums/images/graemlins/ooo.gif
 
   / M4900 throttle spring
  • Thread Starter
#3  
Thanks for the post. If all else fails, stop by the dealer. I have one on my route that has been very helpful. He was not sure but had a M4900 in stock. After following the linkage we found a spring in the lever pivot point under the floorboard. I went looking when I got home. The FEL hoses were routed in such a way that you had to lay under the floorboard to see it. My spring is still there. Guess I'll spray some more WD-40 and see if that works.

Thanks.
 
   / M4900 throttle spring #4  
What speed does your tractor normally idle at. Mine idles at 900rpm. Do you have remotes on your tractor? /forums/images/graemlins/ooo.gif
 
   / M4900 throttle spring
  • Thread Starter
#5  
I think that is about right. I'll check tomorrow. Mine would only idle down to about 1300-1500 when the linkage stuck. From having an old (VERY OLD) tractor before with an inop tac I've got used to operating by sound (except when throtting up with the bushhog). I'll check and post.

As for the remotes--I have one set that came with the tractor mounted at the rear. The lever to control this is located on the right just under the seat. I do not have any attachments that use hydro (YET!!!!). When the dealer installed the FEL he tapped in to this area and ran hoses up to the FEL connection. I really haven't looked at it that closely. Hope that answered your question.
 
   / M4900 throttle spring #6  
So now my 2001 M4900 has the same symptom as you described several months ago, with the non-return to idle problem..... lifting up the pedal up with your foot will bring it down to idle spec.

Did you ever cure yours, and what did you find to be the cause??
 
   / M4900 throttle spring
  • Thread Starter
#7  
There are two pivot points (metal guides actually) under the floorboard leading from the pedal to where the spring is attached to the linkage. I sprayed WD-40 (soaked them) on both points and it seemed to work. The brackets are mounted in a bad place that picks up a lot of trash and dirt. You have to keep them cleaned and lubed. I think they should have put a couple of bearings in the brackets to loosen up the pivot points--oh well.

When it won't idle down, I just clean and spray again.

I looked to make sure the pedal was not bent and rubbing where it comes thru the hole in the floorboard. I know I've hit the pedal a couple of times storing and removing a chain on that side of the floorboard.
 
   / M4900 throttle spring #8  
Thank you for the response and the information. I will be doing a major service this weekend and I will check out the throttle linkage as per your recommendation.

Regards.

David Edwards
Medina, Texas
 
 
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