replaced swing motor 232 hours ago because of complete failure of old motor.Drained hyd tank installed clean out filters.ran machine for a bit to cycle oil and the filter carted system for 4 hours.Now swing motor is out again.I think entire system needs to be torn down piece by piece but my super dosent think so,any ideas anyone?
At the very least pull and clean the hoses and spool for the swing function.
I would check case drain pressure from the drive motors and or look for blown seals in the swivel.
Yeah, you got a good point there, it might be the drive motors flushing crap into the swing motor thru the case drain hose since it Tee's together on top of the swing motor before going to the filter/tank.
yes but wouldnt the machine track crooked?
I would think so...unless both track motors are bad. How weird would that be? I'm still tryin' to figure out how a swing motor craps out in just 230 something hours??? Seems to me, if you had enough debris in the system to destroy a swing motor then it could kill the pumps as well. Just my overtaxed 2 cents. Just what is the swing motor doing or not doing?
The slippers are being pulled off the pistons,cats warrantying the first one or so im told,cat tech says to big of bucket for machine is causing failure,1 5/8 yard cleaning ditches.
That's kinda hard to believe
Is it possible that the swing reliefs are set too high putting excessive pressure on swing motor innards when coming to a stop?
That does sound odd - and wrong. If your Cat 330 can't handle a 1 5/8 yard bucket, Cat isn't what it used to be. Your Cat 330 should be a little bigger than my Hitachi 270. I took off the smaller bucket (with teeth) and put on a clean up bucket off a Cat 325. It's about 64 inches wide and must hold about two yards. Heaped with wet clay, it must be handling three yards. Hundreds of hours of digging heavy clay with that bucket this summer don't seem to have hurt the machine. On the other hand, the dealer is always right, no matter how wrong they may be.
The last swing motor i had that the slipper feet were messed up on was due to the seals in the swivel blown out. When you go to track forward or reverse I would see the case drain line to the swing motor jump. You basically are sending alot of that high pressure for driving the track motors back into the swing motor by way of the case drain line.
I will say that from MY 2 cent worth experience that high case drain from track motors can and often times cause swing motor failures because the track motors case drain connect with the swing. ALWAYS check case drain after a failure. Now on the slipper feet thing, that is kinda rare but happens. Usually you will see the case drain filter actually blow off because its the weak link. When the seals in the swivel are old and flattened and any failure in the system causing metal can if the conditions are right cause a bypass of the drive psi to enter case drain and when that happens look out.
Could you put a one way check valve on the drain port of the swing motor to prevent high drain pressure failures? Or would that cause an anti-cavitation problem? :beatsme
Case drain is just the the amount of oil that is bypassing motors and pumps when they are in operation. You want case drain because it it used for cooling and lube. There is an amount of this bypass that is needed and excepted. When the case drain becomes excessive say in flow then there is wear in the pump or motor. When the pressure is excessive there is blockage in the return to tank. High case drain from the track motors have caused many many swing motor failures even when you had no idea of track problems. So I would say not to put a valve in there for this because you would change the pressure in a way that would be a problem. And if there is high case drain you have a problem that needs to be repaired. An after thought is to change the design all together and run each motor to drain on there own so that they never combine but at the tank but that would be alot of work and engineering with seperate filters and inlets to tank and just not worth it. Periodic testing of case drain is easy and will give indication of early failure. 2 cents only.
Cat tech came out and checked all pressures and also checed for case drain in excess and all checked out good.I did notice that when i took off the reman motor rust trails around the split where the head bolted on i wonder if the motor possibly had rust inside from sitting or whatever,i dunno we will see what happens.