2007 Komatsu PC50 all of a sudden my left track control lever is hard to move and it sticks in whatever position you leave it in, which is nice if i wanted cruise control, but in actually, its a pain in the ass. one day it worked fine, left the machine on the job, rained hard the next few days then i went back and it was stiff? think a joint rusted? im going to pull up the rubber mat today and start poking around. thanks.
Sounds like the plunger in the travel control valve is getting stuck. Probably just need to reseal it.
ok, i finally had some time to pull back the rubber mat and pull off the plastic cover around the travel sticks. below i have a photo with a black arrow pointing at something. is that the travel control valve? (note, the wetness is wd40 i sprayed on it) the side with the right side with the stick still attached works perfect, when pushed or pulled, it returns to center. the side i am pointing to with the black arrow, when pushed or pulled, it stays and does not return. if this is the travel control valve, how do i take it apart and fix it? what can i expect when i take it apart, will springs pop out or ball bearing fly? thanks!
anyone?
Nice pictures (they say a thousand words). Give it a splash with some penitrant oil where it pivots in the body. If it doesn't free up you will have to pull it apart. I bet you will see it once it's apart on the bench. Maybe seals, spring's or just worn out. Post findings. T
Common problem. That shaft has a seal on it and the bearing inside is dry, possibly rusty, causing shaft to stick. Can't get enough penetrating oil in there to lube shaft/bearing because of seal. Typically have to take that unit apart to either clean and lubricate bearing or replace bearing and seal.
well tore into it today. removed the two top bolts and the rocker assembly came right off. i put it in the vise and lubed it up, working it back and forth, it started to free up, but not to my liking. i punched the roll pins out and pulled out each side. right away it was aparent moisture had corroded up the rocker shaft on one side. even the side that worked smoothy had signs of corrosion. i polished each shaft and greased it them up. i then looked at the housing, there is no bearing, but pressed in bushings, i pulled out the shaft seals, polished up all the bushings and scratched out the aluminum oxidation where the seals sat. re-installed the shaft seals and lubed up the bushings. i put back the rocker shafts and pressed the roll pins back in. it now works perfectly. i had noticed one dumb design flaw. komatsu drilled 2 holes in the top of the housing to allow the roll pins to be punched out, which is good, the dumb part is those holes were sealed with the komatus part number tag, water got under the tag and thats how it entered the housing. before re-installing it, i used some permatex ultra grey to fill the holes and i also ran a bead around the base of the assemby to creat a gasket where it meets the valve body. it should be good now! the only thing holding me back now is i dropped one of the stick spacers into the under body abyss? ahhhhh. spent an 1/2hr looking for it. still haven't found it.....
Nice work and pics redline808. That should take care of your sticking lever problem.
Hey the joystick in my jcb mini excavator isn’t working,are there any suggestions on what might be the issue?