Is there anyone face the problem in hydraulic system in Backhole loader about noisy? The used hydraulic oil is ISO VG 68 (following the specified recommendation). Which point should I check in the system? The test results of used oil are in-specification such as Viscosity, Water content, Foamability etc.
Please recommend, Thanks for advance.

Dear Omega

As you had mentioned that the oil is in specification, you should check whether the pump is running starved of oil due to aeration ie: air being sucked in through the suction side of the pump or due to low level in the reservoir or due to choked filters.

Omega,

1. Wear metals,Particle Count analysis helps
identify impending failures.Ensure that
Sample is taken before filter.

2. Check Hydraulic Pump Pressure.

3. Observe any foming in Hydraulic tank.

4. Inspect Lube filters.

Bala.

Omega,

Your problem may not be the oil at all. I would first look at the pump. Check the coupling or pump shaft to see if it is damaged or slipping. Also check the pump to see if it has a bad bearing. Next, check the pump pressure to see that your relief valve is set correctly. Next, check your engine rpms. If the engine is actually working at higher rpms, the pump can be trying to put out more flow than it is rated at. This will cause a noise in your system and can also give indications of air or cavitation due to fluid velocity being too high. Once these are checked, then I would continue to troubleshoot the system from the pump out to the cylinders. Look for leaks, cracked fittings, crimped or damaged lines, etc. This should give you a good start. You can go to www.ihd-usa.com to purchase a fluid power data book. The cost is $1.00 per copy. They have a fairly good troubleshooting guide in the book. Good luck.

I would rather go by Marty in case the prime mover is an oil engine and start from the engine RPM
pl let us know when the problem is solved
regards
Arupanjan