Engine Identification

. ---- USING SERVICE INFORMATION: Normally, information used to identify the size of an engine is given in service manuals at the beginning of the section covering that particular manufacturer.

+++ Examples of the various identification numbers found on an engine.

XXXXXXXX Block foundry; ID and date Engine number NOTE: VIN is stamped on the bedplate 5.0 2355 743 2235 1234 743 3 DATE SEQ NUM B/CODE PLT Label located on valve cover

-- By referring to the VIN, much information about the vehicle can be determined. Identification numbers are also found on the engine. Some manufacturers use tags or stickers attached at various places, such as the valve cover or oil pan. Blocks often have a serial number stamped into them. Service manuals typically give the location of the code for a particular engine. The engine code is generally found beside the serial number. A typical engine code might be DZ or MO. These letters indicate the horsepower rating of the engine, whether it was built for an automatic or manual transmission, and other important details. The engine code will help you determine the correct specifications for that particular engine.

Section 7 for instructions on how to decipher a VIN.

Engine ID Tags Many engines have ID tags or stickers attached to various places on the engine, such as the valve cover or oil pan. The tags include the displacement, assembly plant, model year, change level, engine code, and date of production. Service manuals normally note the location of these stickers or tags on a particular engine.

Casting Numbers Whenever an engine part such as an engine block or head is cast, a number is put into the mold to identify the casting and the date when the part was made. This date does not indicate when the engine was assembled or placed into the vehicle at the factory. A part made during one year may be installed in the vehicle in the following year; therefore, the casting date may not match the model year of the vehicle. Casting numbers should not be used for identifying the displacement of an engine. They only indicate the basic design of an engine. The same block or head can be used with a variety of different displacement engines.

Underhood Label -- Vehicles produced since 1972 have an underhood emission control label that contains such useful information as ignition timing specifications, emission control devices, engine size, vacuum hose routing, and valve adjustment specifications.

Next: Engine Diagnostics

Prev.: Other Automotive Power Plants