Reply To: Vintage Mercury Racer ID Help Needed

[bayham3261]

outboard315 wrote:

There should be a serial number on top of the cylinders or on the flange separating the front and back of the block.

Yes the mark 15, 20, and 25 are dimensionally the same from the exterior. I am leaning towards a KH7 though. I think the fuel pump is bolted to the shifter boss since I don’t see a fuel pump boss on the opposite side. Not sure where it is pulling vacuum from though.

Yes the fuel pump looked a little odd to me too. I just unbolted the pump and it looks like someone drilled a hole into the crankcase to scavenge the vacuum. I guess this is similar to what people do to convert pressure tank OMCs to a standard fuel pump setup. I couldn’t find any serial numbers on the block.

I’m getting the feeling that this outboard may actually be a bit of a Frankenstein build someone did. Whoever had this going was probably only thinking about how to go fast.

A little information is a dangerous thing!