MerCruiser Alpha One Flywheel Engine Coupler 18643A2 18643A5 V8 4.3L 5.0L 5.7L
MerCruiser V6 & V8 (1987-1998) Engine coupler for 14" Flywheels and engines that have a single piece rear-main oil seal. If you have specific questions on compatibility, feel free to contact us.
- This is the 18643A2 Model...
- the A2 Model as the A5 had that tube sticking out of it which covered the yoke shaft. The A2 Model didn't have the greaseable tube, but you can really use either as they are still interchangeable.
- Sierra 18-2323 equivalent
- Note the tape measure.. this would be for the 14" flywheels.
1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996
GM / 4.3L 4.3LX / V6 262 / 175hp 205hp 185hpGM / 5.0L 5.0LX / V8 305 / 200hp 230hp
GM / 5.7L Mag 5.7LX / V8 350 / 260hp 320
GM / 7.4L Bravo Mag / V8 454
Alpha One MR R Gen II
18643A2 18643A5 18643A7 18643A09 18643A9
