SEI 106-1.81 Upper gearcase Alpha One

Description

SEI 106-1.81

• Mercruiser R/MR/Alpha One complete upper unit.
• 1976 to 1982 models with 4 cylinder 470 and 485 models
• 1986 to 1990 4.3 liter V6 engine has 1.81 / 1.84 gear ratio with a 17-19 tooth count.
• Compatible with inline 4 cylinder 3.7 liter motors serial numbers 4208730 to 6225576
• 4.3 liter 185 / 190 horsepower V6 motors serial numbers 6225577 to 0D 469858.
• *Note – before ordering, please measure your output shaft that goes into the engine.
• Replacement upper units come with an output shaft that measures 9-9/16 inch.
• If your shaft is the ‘short style’ which measures 8-1/8 inches, please contact us for availability.