MerCruiser 1623-8266-S 1623-5356A4 Pre-Alpha Lower Unit Gearcase Housing 1970-82

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Part Numbers Included

Stamped Part number is 1623-8266-S which is just the updated version of 1623-5412 that has the flat edges found on the horizontal stabilizer found on the 1982 models

General related part number found in manual is 1623-5356A4 (MC-I & R empty housing) and also slightly related is 1623-4110A6 (Whole assembly)

Item Details

Overall good condition, some damage to the skeg, but ready for all of your internals.
Races are still installed in this. It is advisable to replace the races if you are installing new bearings.
Freshwater Used Part
Original Paint (Missing in some spots)
There are some markings around the pinion area internally, but nothing on the bearing surface areas, so nothing that is going to cause an issue or problems.

Compatibility

Basically this would have been found on MerCruiser (MC-I "120hp" "140hp" "165hp" 470 888 898 etc.) Sterndrives 1970-1982
This is not a suitable replacement for 1983-1990 models which used internals of different dimensions
- Your current driveshaft should have a pre-load pin on the top of it indicating that you're dealing with the right gearcase
This will work for all engine configurations from that time period ... Just a short list below...

Purchase with confidence!

1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 GM Chevy Ford

1623-5412-S1