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Cat 325L no hydraulic power
- Thread starter rclay1981
- Start date
Maybe little too late than s year, unless you like cold weather!
r20d12
Well-Known Member
- Joined
- Nov 29, 2009
- Messages
- 123
- Location
- oklahoma
- Occupation
- heavy equipment field tech since July 1990
Just remembered... (There's nearly 30 years of tractor knowledge to shuffle through)
I once had a trackhoe that had a plugged screen in the pilot passage in the center of the main control valve. It only let the hydraulics of one pump work.
"Suckability" you should write service manuals!
I once had a trackhoe that had a plugged screen in the pilot passage in the center of the main control valve. It only let the hydraulics of one pump work.
"Suckability" you should write service manuals!
Which reminds me: I took a brief look at the Kobelco SK 120 on my way back from another job, that POS was doing half ass job, seems to ran too high of a negcon pressure. Maybe it need the orifices cleaned out. Also was hanging at arm cylinder bottomed out.
I was born in Ukraine, lived in Seattle for 20 years, then moved to Mobile - talking about cultural shock!
I wouldn’t count what goes on in Seattle - rain! It’s more likely he 9 months of non stop drizzle, followiled by 3 months you f scorching heat!
Trash in that thing is highly possible!
rclay1981
Member
So does Anyone have the procedure for checking the PRV?
Hello rclay1981! Want to apologize for highjacking your thread again. I’m afraid I’m going to get scalded by others but my method is remove and plug the hoses and try to use the machine. If your engine boggs down then your PRV is leaking and pump is good. If not - then the problem with the pump. Provided, of course, that you have good pilot pressure all the way to control valve.
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Or you can find 0-10 ampmeter, connect it PRV solenoid in series, at in to PRV signal line with 0-600 or digital gauge, start operating the machine and compare changes of current corresponds with changes of pressure. Or find some kind of current regulating device disconnect solenoid from the machine’s circuit change the current using the device and watch change in pressure.
rclay1981
Member
I capped all three of the lines it didn’t change anything. Their Was zero pressure at the PRV valve with the lines hooked up or capped off while testing. Pilot pressure is 500 psi at test point and 425 psi on top the control valve. I did notice today that the pilot pump line was getting extremely hot really fast like it has internal leakage.
What do you think the chances of the main pressure relief valve going bad all of a sudden is?
What do you think the chances of the main pressure relief valve going bad all of a sudden is?