Mercruiser serial numbers
 

I am having difficulty titling a boat in Ohio. It was previously titled in Indiana and previously in Ohio. Indiana does not require motor serial numbers for I/O motors. When I took the serial numbers off the 7.4 mpi the title clerk said they did not match the previously recorded serial numbers and I would need a letter from the previous owners saying why they do not match. My question is where do I locate the numbers the ones I took to the title clerk came off the engine cover is there a different number on the block. The original Ohio title listed the boat as 330 hp while the mpi serial numbers currently on the boat rate at 310? Precious owners swear that this is the original power. Any suggestions are welcome!

I've never heard of any state needing serial numbers for an I/O engine. Custom built engines and even Merc remans do not even have serial numbers.
I know some states title outboard engines.

may be a tag on the block by the starter.

if engine, transom and drive was package a dealer could get original engine serial number. if original engine there is aluminum tag above starter, 1inch square in size. it would not surprise me if they entered number wrong either on paperwork.

NC requires make, serial no. & HP for any engine of any type over 25 hp. Sent my app back because dealer did not list it, just checked I/O as propulsion type.