EPA04 MBE 4000 ENGINE OPERATOR'S GUIDE Engine Features individual cylinder heads are made of cast iron. The cylinder head gasket is an adjustment-free seal with rubber sealing elements. All MBE 4000 engines are water-cooled, four-stroke, direct-injection inline diesel engines. Each cylinder has a separate fuel injection pump (unit pump) with a short injection line to the injection nozzle, which is located in the center of the combustion chamber. The unit pumps are attached to the crankcase and are driven from the camshaft. Each cylinder has two intake valves and two exhaust valves. The pistons are made of aluminum alloy with ring carriers and a shallow combustion chamber recess.
The pistons are cooled by oil spray nozzles. The crankshaft is precision-forged with seven main bearings and eight custom-forged counter weights, and a vibration damper at the front end. The camshaft is made of induction-hardened steel and has seven cam bearings. Each cylinder has cams for intake and exhaust valves and a unit pump. Charge-air cooling and an exhaust gas turbocharger are standard equipment. The engine has a fully electronic control system consisting of a DDEC-ECU (Engine Control Unit) and a DDEC-VCU (Vehicle Control Unit) connected by a proprietary datalink.
This system regulates the injection quantity and timing using solenoid valves, allowing extremely low-emission operation. The valves are controlled by roller tappets, pushrods, and rocker arms. The intake and exhaust valves are opened and closed by a free-floating valve bridge. There is a force-feed lubricating oil circuit supplied by a gear-type oil pump. This pump is positioned at the rear of the oil pan and driven by gears from the crankshaft. The oil heat exchanger is integrated with the oil filter housing on the right-hand side. Standard engine braking is controlled by a pneumatically-operated exhaust brake on the turbocharger and by a hydraulically-operated constant-throttle system.
For greater braking power, an optional turbo brake is available. The cylinder block has integrated oil and water channels. The upper section of the cylinder bore has a carbon scraper ring seated in a groove on the top part of the cylinder. The six The gear-type fuel pump is located near the front of the crankcase on the left hand side. The pump is driven from the forward end of the camshaft. All information subject to change without notice. (Rev. 04/08) 15 DDC-SVC-MAN-0056 04/08 Copyright © 2008 DETROIT DIESEL CORPORATION