300SD (140.134) L6-3.5L DSL Turbo (603.971) (1993)
Piston: Technical Service Bulletins
Engine - Revised Specs Cylinder Head Bolts/Piston
REF. NO. 01/22b
TO: OUR MERCEDES-BENZ PASSENGER CAR DEALERS
DATE: May 1992
Revision:
Reference to engine 601.91 (non USA engine) removed from sections C and D
SUBJECT:
A.
ENGINES 602.96, 603.96, 603.97
CYLINDER HEAD BOLTS WITH INCREASED TENSILE STRENGTH
B.
ENGINES 601, 602, 603
REVISED TORQUING PROCEDURE FOR CYLINDER HEAD BOLTS
C.
ENGINES 602.91
PISTONS WITH GRAPHITE-TREATED PISTON SKIRTS
0.
ENGINES 602.91
CYLINDER HEAD BOLTS WITH INCREASED TENSILE STRENGTH
E.
ENGINES 601, 602, 603
REVISED MAXIMUM LENGTH OF CYLINDER HEAD BOLTS
A.
Engines 602.96, 603.96, 603.97
Cylinder Head Bolts with Increased Tensile Strength
To allow an increased torque preload on the cylinder head bolts, modified cylinder head bolts with increased tensile strength entered production as of the
engine end numbers listed in the table.
When performing a R&R of the cylinder head on any 602.96, 603.96, 603.97 turbodiesel engine, the previous version cylinder head bolts must be
replaced with the modified version.
The modified cylinder head bolt has a larger bolt head surface and increased tensile strength.
Identification
The modified bolt can be identified by the code number and ribs on the head.