Motor model year identification help please

[joepcdr]

Good evening I picked up what I believe is a 73 Glassmaster 400x. The hull ID is hinting that its a 73, but it might be a couple years newer. The motor that's on it I've been told is the original motor. Its a Mercury 650. Problem I got is I'm having a heck of a time matching the serial number up with known serial numbers. I'm assuming most parts for the 650's are interchangeable. But I'd feel better if I knew for sure. The motors serial number is 4051304 any info passed my way would be helpful. Thanks in advance.

 

[jbcurt00]

Merc 650
65hp
Serial#s 3807833 thru 4571651
1974-1976

Serial numbers 3807833 thru 4136684 were 1974 models

So 1974 and I'd bet only 650s from 1974-76 would have many interchangeable parts.

Most Merc parts are ordered by hp and serial#, not model year.

 

[joepcdr]

Thanks JB - That's kind of what I was seeing. But since this is my first Merc I wasn't real sure. On a positive note the motor does turn free. But the wiring is all janked. I haven't had a chance to do a compression check on it yet. But was going to do that once I got it off the boat. I pulled up all the rotted carpet and wood this evening off the deck. Got lucky that somebody did try to replace the deck at one time. So the stringers are in pretty good shape.But they used the wrong type of foam etc. So right now I've got a pickup bed full of crap I pulled out of this thing.