TOPIC: Can't id engine. year, size, etc.

I just picked up an older, 50's, elgine with a mercury motor. I can not find a data base with serial numbers that go as low as mine. This is the info I have: Serial number is 1249916, Marked on plate as a Mark 78AE, Made in Cedarburg, Wa. Also marked on engine is "Super Marathon Engine". "Dyna Float" on lower. Has a single screw on bottom of faceplate to secure. Faceplate says Merc 800, but might be replacement. My guess is a 1959 700 DR with a LH prop?

The year/model would be 1959 Mark 78A and they did make a counter rotating engine for dual set ups..oldmercs.com listed under the "Mark" icon on the left side of home page,picture with proper faceplate is there.Nice find!!

Thx for the info, so it is a 70 h.p? I am restoring motor and boat so I probally have more questions in the future. Now to i.d. the old Elgin. Thanks again for the help

Thx for the info, so it is a 70 h.p? I am restoring motor and boat so I probally have more questions in the future. Now to i.d. the old Elgin. Thanks again for the help

Yes, the 66 c.i. Mark 78A has an output of 70hp at the crankshaft. The Left Hand prop rotation, BTW, was standard on a Direct Reversing motor.

HTH & Congrats on your find...........ed