Serial Number Mystery - SOLVED?

[DJ_Allatoona]

Hi y'all...a mystery here. Is this my motor's serial number? These RAISED numbers are on a black plate screwed to the motor, near where the steering cables go in, on the starboard side, just behind and below the removeable panel:

5488608

It LOOKS like a serial number, but it does not match up with any of the Mercury serial guides or part books that I've seen. It does come up in the serial range as a 70 HP 3 cyl...but there's no way. It has 4 cylinders. I understand the motor is a 1986 75 HP...but a know-it-all guy at a parts store says somebody may have dropped in a different powerhead? Is that even possible?? Need some help here.

Here's two pictures....not great, but might help. Thanks!

 

[zzzzz]

Re: Serial Number Mystery

Re: Serial Number Mystery

the 4 cylinder 75's started with #64xxxxx so you need to look on top of your block for a silver plug with a 7 digit number stamped in it and that will be the serial number of the powerhead- it sounds like the powerhead has been replaced

 

[Laddies]

Re: Serial Number Mystery

Re: Serial Number Mystery

Well for sure it's not a 1986 of any HP and it's not a 3cyl of any HP it looks like a 50HP and if that number is stamped it to the plate in the tilt bracket it would be a 1979. It also could be a 80 but you need to take the cowl off and on the starboard side of the engine there is a raised plate with Thunderbolt or some other name cast, not stamped in it let us know what it says

 

[DJ_Allatoona]

Re: Serial Number Mystery

Re: Serial Number Mystery

OK, well I found a decal on the tilt bracket with a funky number on it. The number is:

0A984714

According this website http://www.marinshopen.se/ which shows the serial ranges and models, if I drop the "0", I find the rest of the number as a 1986 75HP 4 cylinder. Check it:

So this little dilemma appears solved, unless I'm reading it wrong (which is possible). Appreciate all who responded.