mercruiser prop numbers

[Pikey23]

Does anyone know what the mercruiser part numbers mean?
Here is my issue I have a Model 48-78120-A4 19P prop. I need a new one and found a great deal on a reconditioned Model 48-78120-A4OL 19P. What does the OL stand for? Are the last digits where it was made? I need to know asap so I can have it for the weekend. Thanks in advance.

 

[usskydvr]

Re: mercruiser prop numbers

The 19P is the pitch. Merc made the following variations of your prop number 48-78120A4 , 4878120A40 , 48-78120A45. only minor model number changes. all are the same
14 x 19 3 blade Aluminum

 

[pargueraboatpr]

Re: mercruiser prop numbers

I own a KeyWest 2003 with a Mercury 140 HP. The propeller is a 48-78120A40 with a pitch of 19. I use the boat for talking customers for SCUBA and snorkeling. Any recommendations as to change the prop for a same one or a better performance one ?

 

[leafan69]

Re: mercruiser prop numbers

Can I add another question re props? I have an extra 21 pitch Merc prop from my 4.3 Mercruiser. Will it work on a 5.0 Mercruiser (both are Alpha 1 legs). Part number 78122-21. Thanks
Rob