MBE 900 OPERATOR'S GUIDE The cylinder block has integrated oil and water channels. The upper section of the cylinder bore is induction-hardened. The single-piece cylinder head is made of cast iron. The cylinder head gasket is a medal-elastomere, adjustment-free seal with Viton® sealing elements. The oil cooler is located near the front of the crankcase on the right-hand side near the water pump. The gear-type fuel pump is bolted to the front of the crankcase. The pump is driven from the forward end of the camshaft. The pistons are made of aluminum alloy with a shallow combustion chamber recess. The pistons are cooled by oil spray nozzles.
The air compressor, with a power-steering pump attached, is driven by a gear on the camshaft (optional). The crankshaft is precision-forged with seven main bearings (five on the 4-cylinder engine), six of which have custom-forged counterweights (four on the 4-cylinder engine), and a vibration damper at the front end. The vehicle is cooled by a closed system using recirculated coolant; temperature is regulated automatically by a thermostat. The alternator and coolant pump (and any other accessories) are driven by a belt with automatic belt tensioner. The camshaft is made of case-hardened steel and has seven main bearings (five on the 4-cylinder engine).
Each cylinder has cams for intake and exhaust valves and a unit pump. Electrical equipment includes a starter and an alternator. Exhaust Gas Recirculation The purpose of the Exhaust Gas Recirculation (EGR) System is to reduce engine exhaust gas emissions in accordance with EPA regulations. The valves are controlled by mushroom tappets, pushrods, and rocker arms. The intake valves are opened and closed by a valve-guided bridge. The EGR system consists of an EGR cooler, EGR valve, reed valves (on the MBE904/924/926 only), and an EGR mixer. There is a force-feed lubricating oil circuit supplied by a rotary oil pump.
This pump is positioned at the front of the crankcase and driven by gears from the crankshaft. The MBE 900 engines for on-highway EPA 2004 regulation applications use a cooled EGR system. All information subject to change without notice. (Rev. 04/08) 23 DDC-SVC-MAN-0055 04/08 Copyright © 2008 DETROIT DIESEL CORPORATION