Part Number: GLM21120
Price: $16.9500
Quantity: 
Nut Cover for Mercruiser Mercury Mariner Large Gearcase 79448
Cover Nut for Mercruiser R, MR, Alpha One, Gen. II, Bravo 1 ; Mercury/Mariner Inline/V6.
Holds bearing carrier in the lower unit.
Many times its better to drill the old nut on two sides and break it to get it out. That will give you a chance to clean the threads before installing a new nut. Many times trying to get the old nut out in one piece cracks the lower unit housing which is very expensive.
OEM: 79448
Note: Does Not Fit Bravo 2 Or Bravo 3