For A&V waterjet pump, we recommend changing hydraulic fluid yearly, the hydraulic oil type is #46.
1. Open the back panel, use a 10mm Allen key to lose the plug red circled in the picture below, then the oil will by drained by gravity .
Or open the top cover of the oil reservoir, use an oil suction pump remove the old hydraulic oil. (notice don’t drop the seal rubber inside the reservoir)
2. Refill the tank with 46 hydraulic oil.
3. Degassing of the hydraulic pump, in the front of the pump, there is a Rexroth Hydraulic pump, on the back of the Rexroth hydraulic pump, there is a degassing cap, use 10mm Allen key lose that cap, and wait a while until hydraulic oil flow out.
4. Re-tighten the cap, and take a test run. Any abnormal sounds contact us.