Engine: Description and Operation

The Oldsmobile four stroke cycle diesel V8-350 engine is basically the same in construction as the Oldsmobile gasoline V8-350 engine. The cylinders are numbered 1, 3, 5, 7 on the left bank and 2, 4, 6, 8 on the right bank. The firing order is 1-8-4-3-6-5-7-2. The major differences between the diesel and gasoline versions is in the cylinder heads, combustion chamber, fuel distribution system, air intake manifold and method of ignition. The cylinder block, crankshaft, main bearings, connecting rods, pistons and pins are of heavy construction due to the high compression ratio required to ignite the diesel fuel. The diesel fuel is ignited when the heat developed in the combustion chamber during the compression stroke reaches a certain temperature.
The valve train operates the same as in the gasoline engine, but are of special design and material for diesel operation. The stainless steel pre-chamber inserts in the cylinder head combustion chambers are serviced separately from the cylinder head. With the cylinder head removed, these pre-chamber inserts can be driven from the cylinder head after removing the glow plugs or injection nozzles.
On 1980 models and 1981 models except California, the glow plugs are threaded into the cylinder head and the injection nozzles are retained by a bolt and clamp. On 1981 California and all 1983---84 models, the glow plugs and the injection nozzles are both threaded into the cylinder head. The injection nozzles are spring loaded and calibrated to open at a specified fuel pressure.