If clutch are fitted:
Do not engage the clutch at a lower speed than “Clutch engagement speed”. Avoid clutching in at lower speed, as the clutch oil pressure may be too low. It should also be avoided to clutch in at higher speed as this may load the clutch unnecessarily.
When the gearbox is driving pumps with low resistance, for example fire fighting pumps, the inner friction in the hydraulic operated clutch may be higher than the resistance in the pump, causing the output shaft to rotate when the clutch is disconnected. This is no functional fault.
The gearbox is not filled with oil when delivered. The oil level can be checked by means of the dipstick when the gearbox is stationary. Approximate quantity is specified on the identification plate on the gear case and also the recommended grade of oil. It is essential that the clutch does not touch the oil because that may generate additional heat.
The gearbox lubrication oil spray from the internal nozzles may be observed through the inspection windows.
Check that the cooling water is passing through the oil cooler at the required rate of flow. The water inlet and outlet connections on the cooler are interchangeable on a two-pass cooler.
A high quality mineral oil with EP additives, having good anti wear performance with low corrosion, oxidation and foaming properties must be used. The oil must meet the FZG A/8,3/90 load stage 12+.
The oils listed below have been used with good experience. If you wish to use other equivalent gear oils, contact your oil supplier, ensuring the mentioned requirements are met.
Note: Any extra additives must not be used. In such case our warranty will not be valid.
Oils for NORGEAR gearbox with built-in clutch: ISO VG-68
Oils for NORGEAR gearbox without built-in clutch: ISO VG-150
Synthetic oil grades meeting the above requirements in addition to be compatible with mineral oils may be used. Contact your oil supplier for recommended grade.
Normal oil temperature in the gearbox sump will range from 40 - 70 deg. C. The temperature switch is set at 80 deg. C and it will initiate an alarm at higher temperatures.