2003 Volvo BL70 backhoe has been running good and today the front bucket rotates and lifts up and down, but very very slow. I suspect that the servo pump has to be replaced. Looking for maybe alternatives I did not think of? Duane
Everything else running normal
Welcome to HEF, Duane ! How well does the backhoe functions work ? Changed hydraulic filter yet ?
New filter, new fluid, everything else works perfect.
Also, the bucket when raised very slow, when I let go of the control this bucket slowly starts down on its own like I am loosing pressure but there are no big leaks, I think is backfeeding back through the servo pump.
Thanks for letting me be a member of this site.
You likely have a failed piston seal . Internal leakage back to tank. Does the boom drift as well? If you check cylinder temps, the hot one will be most likely source of leakage. The other possibility is, your centering spring may be loose or broken for the bucket spool. Again, heat will give you a quick idea of where to begin looking. Good luck
Thank you funwithfuel for the information, I am checking that today. Another interesting fact is if I turn off the servo solenoid switch on the side panel where the gauges are, then wait 30 seconds at about 1500 rpm or higher, then toggle the switch with the bucket handle in a working position (maybe straight back for raising front bucket), then the front bucket moves at normal speed for about 3-5 seconds, then back to slow speed. Thoughts?
Also, thanks to BLS Repair and Tinkerer for their earlier help.
Dirty fitting (filtered fitting) at RCV for loader control. I don't currently have schematics in front of me, but excavators typically have a filtered inlet fitting at the RCV. It will look like the old bronze carburetor filters.