Safer Wholesale carries
virtually every marine flywheel ever used in marine applications. There
are only two flywheel sizes used in GM based marine engines: a 12¾" and
a 14" flywheel (true inboard flywheels are always 14" with the ring
gear on the outside edge of the flywheel). The crank bolt pattern of
each engine (where the flywheel mates on the back crankshaft), is
different for each engine. Simply said, a 14" flywheel from a 4.3L
engine will not fit or bolt on a 5.7L engine, even though they are both 14" in diameter.
ordering a flywheel, first measure your flywheel diameter (most are
14"), identify the YEAR of the engine, then identify your exact engine
(3.0L, 4.3L, 5.7L, etc).CALL 1-866-606-3991
7.4L (454 ci) 14" inch flywheel made for 1991 and later 7.4L (454 ci) marine engines.
If you have an existing 7.4L (454 ci) marine engine with an existing 14" flywheel made before 1991 (commonly referred to as a two-piece rear main seal or split seal) and are replacing it with a 1990 and LATER 7.4L (454 ci) engine (commonly called a one-piece rear main seal or full seal), then this 14" flywheel is required.
Brand new 7.4L base marine engines do NOT ship with a flywheel.
This flywheel is unique to a 7.4L engine. It will only fit and install on a 7.4L engine made from 1990 to present.