# stuck hydraulic track adjuster



## agmantoo (May 23, 2003)

I have a stuck/locked in place hydraulic track adjusting cylinder off a track hoe. While on the machine the shaft would slide inward with the relief valve open. With the relief valve closed as it should be, I cannot get the shaft to extend while on or off the track hoe using the fill valve. The fill valve is new and it works. I have fabricated a fixture (3/4 inch grade 8 bolt & nut and a 1 inch air wrench). I have both tremendous pushing power to the piston side of the shaft using a 6000 PSI grease gun on the fill valve plus the pulling power from the fixture onto the shaft. I have also been soaking the bore area with PB Blaster. I do not have access to any explosives. Any thoughts?


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## Wis Bang (Feb 20, 2009)

Was it bottoming out alot? Maybe the inner end mushroomed/peened over.


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## agmantoo (May 23, 2003)

Wis Bang
I have not had this machine very long. I became aware of the problem when I was going to take some of the excess slack from the track. I could not get the track to tighten regardless of what I tried. I then opened the relief valve and immediately the track tensioner shaft permitted the track to get more slack as the shaft was allowed to withdraw into the cylinder. I again tried to tighten the track and the shaft refused to extend regardless of what I tried. At this point I removed the track adjuster from the machine and thus far I have not been able to get the shaft to extend. I do not think the end of the shaft is mushroomed and up to now in my period of ownership the adjuster had managed to hold the track with tension but with just needing a little slack removed to hold the track properly.


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## Wis Bang (Feb 20, 2009)

Perhaps the inlet is blocked since you let the grease/pressure out but can't get any to go in. Can you chain to to a fixed point and pull on it w/ something?


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## grimm_mojo (Dec 30, 2007)

i use work with hydralic presses so i not sure if the track hoes are similar or not. on the hrdralics i had to work on some times the actuators valves not working right or sticking. there the coil packs on them to that can go bad an not work. but myself i pull the cyclinder apart an see how the seals an rings look like could have one messed up or wore out letting it only work one way


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## agmantoo (May 23, 2003)

At this time I am putting, by my best guess and some calculations, ~48000 PSI on the locked cylinder and at most I have heard either 6 or 7 creaks and observed no travel. I have a witness mark on the shaft and visually I cannot see that the shaft has moved. It appears that I may have to make a trip to Oak Ridge and get some of the stuff they are known to make. I heard that following the dropping of the A bomb a farmer wrote them saying he needed a little of "that stuff" as he had some stumps that he needed to remove.


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## dirty (Oct 14, 2005)

have you tried adjusting it with the track off the ground?

is it possible the track has been stretched beyond the adjusters max extension?

can the track be shortened a link or two?


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## agmantoo (May 23, 2003)

I initially tried to adjust the track with the track off the ground. There is plenty of room left for adjustment IF I could get the adjuster to work. Thanks


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## VonWolfen (May 24, 2004)

This may work. Release the pressure off of the track and gain some slack. It you cant gain 3" or so of slack, use a short piece of railroad tie and your bucket to push on the track. Get everything PBed and cleaned, then chain your bucket to the track and prestress the track forward. Apply your adjustment grease and have someone pull with the bucket at the same time. May take a couple of tries back and forth.


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## agmantoo (May 23, 2003)

Success! Every time that I went by the shop I stopped and tightened the fixture with the 1 inch impact wrench and gave the fill valve a shot of 6000 PSI grease. Late this evening I saw that the witness mark had moved just a bit. I then started alternately torquing the fixture and pumping grease plus some heavy jolts with the 2 lb hammer. Slowly and reluctantly the shaft begrudgingly exited. It appears as if someone may have needed a ground for a welder and use the shaft and an arch inside the cylinder seized the rod to the cylinder. The rod and the bore are just a slip fit when everything is perfect so it would be easy for the current to jump from the rod to the cylinder wall. I will hone the cylinder and may get a replacement rod depending on how well I can polish the defective areas, saving not less than the $650 plus shipping for an aftermarket replacement adjuster.


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