May have been covered at some point, no luck finding it. Have a CAT 330Cl, japan model, when first starting to run it the swing acts like it has air in the system along with the left track only. If you run all the functions, boom, stick, bucket etc. and let it idle and get a little heat in the fluid everything runs smooth. The. Every so often, if swinging whilst tracking left or right, the swing will shake essentially at the start of the swing then be smooth. I’m thinking maybe a relief valve or spool valve issue maybe??? Not sure where to look seeing how I have 0 shop info on it(company is cheap). So I’m trying to blindly diagnose and repair this worn out junk lol. Need help where to look Thanks
Hmmm I’m going to ask about the basics just in case...as always include S/N when you post so those of us with SIS can take a look at specific info. Fluid level where it should be? Recent filter changes? As in all of the hydraulic filters, should be three on that one. Two spin-on non-op side in the door with the oil filter and then the return in the tank. Initially it sounds like a suction issue like it’s getting some air. I’ve also seen them act funky like that when the powershift solenoid takes a dump. On our drill rigs it uses both pumps to run the rotary and if it won’t kick them both in like it should it won’t hardly turn an auger in tight clay. Do you have a pressure gauge to test pressures?
Ok. I have changed all filters yesterday and was thinking it was getting air some how but haven’t seen any leaks or seeping after shut down, have noticed that the tank keeps pressure on it, not for sure if that was normal or part of the problem
Pressure in the tank is normal. Cat did some interesting plumbing on those. Resolver valves and whatnot. What’s the S/N?
Leaks on the suction will show up overnight if you don’t release in tank pressure. Did you check suction strainer?
I would suggest checking for codes on the display before doing any wet work.