Almost done giving my 2000 hitachi EX35U a quick restoration. At one point in the project I realized the fluid leaking from one of the final drives in the motor chamber of the undercarriage was actually gear oil. The final drive flange that bolts to the undercarriage was cracked and the crack went through to the inside of the gear oil side of things. Had my machinist braze the crack and grind it all back down as proper as he could for only $400.
went to get new seas for this final drive but the dealer gave me parts that didn’t match and insisted they were for my machine. After some search the dealers parts guy and I determined that seals and gear box cover locking ring matched that of a ex75! Another thing was when I pressurized the swash plate piston to pop it out I noticed no spring came with it as shown in the manual but then again my manual is for EX35U final drives and these resemble 75 finals.
I installed the spring behind the swash plate piston, put everything back together and right of the bat the track with the recently serviced final would not move, the pump didn’t even sound loaded when I pulled the lever. Jacked up that side of the machine to get the track off the ground, pulled the lever and it started moving. Month later and it still does this sometimes when the machine has been off all night, it’s fine usually all day when running it. To get the track going you just lift that side up.
my question is is there air still in the system, is that spring causing this problem, has anyone experienced this. Again when the track won’t move and I pull the lever the hydraulic pump doesn’t sound like it’s under load. And if there is air the that pistons circuit then I don’t have the two speed hooked up yet to see if I could purge it with that. Idk, it’s just personal machine that gets used around the property which is why I didn’t opt to replace the final drive. And when I took the final drive apart it looked brand new inside.
thanks for any help
went to get new seas for this final drive but the dealer gave me parts that didn’t match and insisted they were for my machine. After some search the dealers parts guy and I determined that seals and gear box cover locking ring matched that of a ex75! Another thing was when I pressurized the swash plate piston to pop it out I noticed no spring came with it as shown in the manual but then again my manual is for EX35U final drives and these resemble 75 finals.
I installed the spring behind the swash plate piston, put everything back together and right of the bat the track with the recently serviced final would not move, the pump didn’t even sound loaded when I pulled the lever. Jacked up that side of the machine to get the track off the ground, pulled the lever and it started moving. Month later and it still does this sometimes when the machine has been off all night, it’s fine usually all day when running it. To get the track going you just lift that side up.
my question is is there air still in the system, is that spring causing this problem, has anyone experienced this. Again when the track won’t move and I pull the lever the hydraulic pump doesn’t sound like it’s under load. And if there is air the that pistons circuit then I don’t have the two speed hooked up yet to see if I could purge it with that. Idk, it’s just personal machine that gets used around the property which is why I didn’t opt to replace the final drive. And when I took the final drive apart it looked brand new inside.
thanks for any help
