I need some help!

[No Interest]

I am new to this and I am a little confused. This is what I have going on: I thought it would be fun to build a little hydroplane. So I did. I have a motor for it but I decided I it was not really the look what I wanted. Now I have a 1958 Mark 25 power head and a H tower but I am lacking a lower unit. Can some one please help me figure out what I need. I am unclear of the differences in an "A", "B", "C' and "Q" lower units. I know some had a longer skeg, and different gear ratios. What would be the best choice for me. This boat is for fun only. One more thing, What do you want to avoid when looking for a gear case, welds, shortened skeg, pitting, filler, paint? How do you know what you are getting when you take the chance and buy something you have no way of looking at first. I know these things are very expensive and are very hard to come buy. What is the best way to start, with an empty case and new parts or take your chance and buy one on ebay and tear it down and replace what is needed? Thanks, Ian Kramer

[Ed Hatch]

There was two Quicksilver tower heights. The Q is the earlier and taller version and Merc changed over to the H in 1953.


There was also two skeg configurations, the original earlier version had the triangular skeg and in 1956 Mercury switched over to the deeper skeg with the squared off bottom.

There were two gearsets available, 1 to 1 and 16/21.

The ABC gearcase will fit your tower, the deeper skeg will allow you to jack the motor up a bit and prop selection is based on your boat and the gear ratio you happen to have. If you find a Q length gear case I suggest you consider buying it as there are new H length drive shafts available.

[No Interest]

Ed, Thanks for the response. Who rebuilds these units and is there one stop shopping for parts? Thanks

[capnzee]

There was a fellow in the Chicago area who called himself the "foot doctor". That is about all I know, but he seemed to be able to handle rebuiling of all of the Merc lower units.