2005 250 4 stroke will not spin the starter

[mailman1]

I have a twin set of 2005 250 4 strokes. The port motor acted like a dead battery just clicks when key turned. I replaced the starter and tested all fuses and swapped out relays. Same end result! The 4 batteries all test the same and I see 12 volts where the cables attach to the motor. I have the switch on the battery box set to "ALL BATTERIES" the starboard cranks right up. The port engine barely produces a faint click. What next, Please. THANKS!!

[DennisG01]

The first question would be why would you replace stuff without diagnosing things, first?

Even though you may see 12V somewhere, it doesn't mean that there's enough amps going through.

-- How did you "test" the batteries?

-- Next would be to inspect ALL electrical connections - start at the battery, follow every black and red wire - through the switch and eventually to the engine. Remove, visually inspect, clean and reinstall. A quick visual is NOT enough... unless there's something obviously loose/corroded, of course.

[99yam40]

Need to be reading voltage while the motor is just clicking.
start at the battery switch and work to the starter.
you are loosing good connection somewhere between there if one motor turns OK and the other does not.

Just a thought, did you remove the cowling and watch to see if the starter is engaging the flywheel when it is clicking?

Could be that the starter cannot turn a motor do to power head, lower unit, or drive shaft binding