Home › Forum › Ask A Member › 1965 40 Johnson Fuel Pump › Re: 1965 40 Johnson Fuel Pump
July 24, 2016 at 4:28 pm
#40816
Depending on the application (space limitations) I find that the larger pumps work much better with today’s fuels. Don remember the vapor lock issues OMC ran into with the 9.9/15s? They went to the large pump to cure that. I think the large pump for the Big Twin would be #438562. Notice it mounts for the vaccum port and has the small outlet nipple. There use to be a pump you could order that came with multiple size outlet nipples? The nipples just screw in with an oring for the seal. The large pump is actually cheaper & a much better pump. Easier to rebuild to boot if need be in the future! Just my opinion!
Dan in TN