Pralhad Birdi
Well-Known Member
Hi all,
I’ve got a Komatsu PC30UU-3 Serial No. 13417 mini excavator that has slow and overheating hydraulics. Works fine when it’s cold, but once it’s worked for a couple of hours, will struggle to lift the boom (very slow) and sluggish controls all round.
Machine starts up fine and has plenty of power on the lowest idle - will lift itself off the ground with all controls. Boom is able to lift the machine off the ground at idling, but when you pull the boom back up, there’s a slight delay before it lifts off the ground.
And then immediately you rev up slightly past idling with all controls neutral, there’s a hissing from the main control valve that sounds like a spool is out of neutral or there’s a restriction in flow back to the tank.
I’m suspecting possible low pilot pressure, but I’m not sure.
Being a zero-swing machine, everything is very tightly packed in so I’m not able to locate the PRV or find the pressure testing ports.
Would appreciate any advice.
Thanks
I’ve got a Komatsu PC30UU-3 Serial No. 13417 mini excavator that has slow and overheating hydraulics. Works fine when it’s cold, but once it’s worked for a couple of hours, will struggle to lift the boom (very slow) and sluggish controls all round.
Machine starts up fine and has plenty of power on the lowest idle - will lift itself off the ground with all controls. Boom is able to lift the machine off the ground at idling, but when you pull the boom back up, there’s a slight delay before it lifts off the ground.
And then immediately you rev up slightly past idling with all controls neutral, there’s a hissing from the main control valve that sounds like a spool is out of neutral or there’s a restriction in flow back to the tank.
I’m suspecting possible low pilot pressure, but I’m not sure.
Being a zero-swing machine, everything is very tightly packed in so I’m not able to locate the PRV or find the pressure testing ports.
Would appreciate any advice.
Thanks