• Check the rubber coupling for tears.11GUID-E7E9A2B6-8596-4838-8550-CA4F323760D61. Rubber coupling• Change the rubber coupling when needed.It is recommended to let an authorised Valtra workshop change the coupling.4.7.4.21 Checking and greasing the trailer air-pressure brake systemCheck and grease the trailer air-pressure brake system periodically.1. Grease the rubber surfaces of the trailer quick couplings with Calsium LFgrease.2. Check the integrity of the system.The system has to be air tight so that after stopping the engine, the pressuredoes not decrease more than 0.15 bar during 10 minutes (2%). Whenneeded, repair the leaks.4.7.4.22 Checking the air pressure system's automatic water drainingIf the tractor is equipped with an air pressure system (extra equipment), there is apressure air reservoir under the cab. If the tractor is equipped with pneumaticbrakes (extra equipment), there are 2 pressure air reservoirs under the cab. Thereservoirs have automatic valves for water draining. The valve functions must bechecked frequently.4. Maintenance- 309 -
