Engine Builders: The following information regards cylinder liner adjustment and compression ring gasket thickness for Detroit Diesel Corporation (DDC) 71 Series diesel engines.
This information should be considered any time liners are replaced. AERA previously published TB 206 concerning compression ring gaskets. This supplements that information.
The correct position of the liner top flange is .045-.050? below the deck of the block and there must not be over .002? difference in the depth between any two adjacent liners when measured along the cylinder longitudinal centerline.
Compression ring gaskets are color coded on the top surface with a 3/4? black, white or orange stripe to indicate compressed thickness (see Chart 1).
To adjust individual liners, .002? shims are available with p/n 5199569. This shim must be installed underneath the liner insert and may be used only in the current “high” deck blocks. Liner inserts are also available in various thicknesses (.1795-.1800?).
Engine Builders: Crankshaft changes have been made to 1998-2003 GM 4.8, 5.3, 5.4, 5.7 and 6.0L engines. The flywheel flange thickness has been changed in some of the engines listed above.
Later crankshafts have a shorter flywheel flange as seen in the listing below. These changes are due to the many different vehicle and transmission combinations supplied by GM.
A flywheel spacer ring GM p/n 12563532 and a longer bolt set GM p/n 12563533 is required when using a later thin flange crankshaft to replace an early thick flange crankshaft. Also, if the crankshaft is being used in a vehicle, which has a standard transmission, a pilot bushing GM p/n 12557583 is required.
NOTE: GM part numbers correct as of October 2003 (see Chart 2).
All GEN III engines in Camaros, Corvettes and Firebirds have a .857? thin flange and a freeze plug installed at the bottom of the pilot shaft hole; the 5.3, 5.4 and 6.0L engines don’t have the freeze plug.
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