Re: Trying to identify year of this Johnson 5.5HP
I also believe it's a '59 model and that the price is at least $100 too high if not more. As Samott wisely told me once....."they all run good in a barrel".
The motor may have a leaky lower unit, a bad clutch dog, or may be running on one cylinder and need coils. And the impeller probably needs changing, too. I'd never pay $400 for a used 5.5hp motor. There's a million of them out there. Also, if the serial/model number plate is missing, I believe that's a good indication that some funny business went on with that motor in the past. Those serial number plates are riveted to the tiller bracket and shouldn't come off without help. i've got early 50's motors that all still have their model number/serial number plate and it's still on there good. I believe in my state if the warden sees you fishing with a motor that has no serial number on it, they'll confiscate it right then and there.
I think this is one you should pass on if the seller doesn't get right on the price. I'd sell you a really nice 7.5hp evinrude for that price with new coils, new impeller, and perfect lower unit.
JMO,
JBJ
BTW, a 5.5hp OMC from the 50's or 60's is a super motor, and that one could be a good one, AND you would probably get your money's worth out of it even if you spent $500 on it. However, the price is a little high.