Starting and running Reductant pump When the reductant pump is new, the check valves may need to be slackened. IMPORTANT! Blow the reductant pump suction nipple with compressed air (approx. 6 bar) for at least 3 sec- onds before starting the engine for the first time. 336 838 Reductant pump OPM 100 en-GB 24 © Scania CV AB 2015, Sweden