I just purchased a 490e, 95 I think. Runs great operates well. Used it about half a day and everything was working fine. Then the track speed all of a sudden was nothing. Let it cool down. Seemed to pick back up a little. But not to where it was. If I load the other hydraulics, such as bucket curl it seems to work a little better. As in hold the joystick even after full cylinder travel. I'm guessing that perhaps a solenoid or valve someplace may be sticking ? It did sit for a while before I got it. I don't have a manual so wondering where things to check might be located. I let the machine cool for a while and the tracks went fast for maybe 5 min or so, then back to slow and not moving Thanks!
Sounds like someone might have ****ed around with the servo valve on the PTO pump which will change your flow rate of oil under load and when the oil viscosity changes due to temperature.
Would that cause track only? When cold or after sittings tracks work great plenty of power. After digging for a few then try and move tracks slow down and then just stop. All other hydraulics are strong and fast. Just got the machine may have more issues that apparent at inspection... Seems to get hot and over heat as well. And way more hydraulic leaks than a two hour test showed. Track speed is first thing I need fixed. Machine hot does not move, both tracks are the same no different. Cooled off, moves good again. Tests I can do? Before taking it to the dealer?
what did you find out? what did you find out?
If you can work out the equivalent Hitachi model i may be able to help. I know some of the older EX range of Hitachi's had 2 main reliefs in the control valve. One for the front attachment and swing. And one for the travel. if this is the case you can swap both relief valves as a temp measure to test. They're both the same valve, its just the pressures that differ.
Sounds to me like maybe the center swivel seals have let go.
I changed the rotary manifold still same issue.. Anyplace I can get an online service manual? Also it's major overheating 20 min of work and it's done for 45 min. What a mistake this thing was to buy! Anyone want a cheap490e?!
Still at a loss on this. Spending way to much money that what it's worth... Just wanna get it so it moves! Any other ideas?!