1956 Thompson Off-Shore with twin Mercs

LancerBoy · Post by **LancerBoy** » Tue Dec 06, 2011 7:42 am

Check out this NEATO picture. From a 1956 "Small Boats Guide" I found at a thrift store.

The boats are both Thompson 18 ft. Off Shore models and each has twin Mercs. Can any Merc guys ID the motors and their HP?

Andreas

Torchie · Post by **Torchie** » Thu Dec 15, 2011 7:02 am

They look like Mercury Mark 55's. That would also be consistant with the year of the pic. I believe that they were 40 hp motors and look to be short shaft.

One question though Andreas.
The transom cut out appears to be lower than on my 1955 Off Shore hence the use of the short shaft motor. Was the height of the transom cut out something that could be ordered from the factory or did a dealer do this afterwards? It seems like the majority of older outboards that I see have the short shaft set up. My twin Johnson's are the long shaft set up.
Just curious,
Karl.

LancerBoy · Post by **LancerBoy** » Thu Dec 15, 2011 9:05 am

The factory offered transom height for either long (20") or short (15") outboards. The smaller boats and strip-built hulls were only available with 15" transom.

Andreas

Torchie · Post by **Torchie** » Thu Dec 15, 2011 9:23 am

Great to know Andreas.
I may be going to look at another Off Shore. Registered as a 1957. I will see if I can get the numbers off of it.
Karl.

JoeCB · Post by **JoeCB** » Thu Jan 05, 2012 3:14 pm

the short shaft motors and the deep cut-out sure make for a clean streamlined profile... HOWEVER I don't think that I would like to get cought in a sizable following sea swell even considering the motor well bulkhead.

Joe B