I have a terex hr16 mini trackhoe and sometimes there is a prety loud noise coming from the hydraulic pump and then it will stop. It is full of oil and seems to work ok
To rule out suction side, clean/alt remove suction strainer, breather and check suction hose for inside collapsing alt kinks....noise might be cavitation.....
Does it happen when you first start-up...then go away?.....If so then it could be a shaft seal leak on the main pump (sucking air or loosing prime while sitting and not running)
It's me again with the growling hydraulic system on my terex excavator. i've determined that it starts doing it after it gets hot' I'm looking for a replacement filter but can't find one also i'm thinking of changing all the fluid since it's had various mixtures in it any other suggestions would be appreciated thanks it's a terex hr16
That noise you are hearing from the pump is probably cavitation. and the sound is caused by the bubbles in the fluid collapsing, and this can erode the metal in the pump.
If that pump is cavitating to much, you will soon need a new pump.
Are you using manufacturer recommended fluid? Check for restriction on the suction hose. Check strainer in tank if any.
It would not cost to much to have someone put a flow meter on the system and verify normal or abnormal condition.