merc lower unit

[switzerbullet]

What type of lower is this? Sam? It has a large open exhaust opening.

[Skoontz]

Not ever being a Merc person, I will guess by looking at the exhaust outlet and nose cone that would fit the 100 or 110's. Deny Anderson had a flat bottom Hondo with a 110 Merc grenade and a gearcase that was very similar to what you have there, but, it will be interesting to see from those who know lots more what it really is:)

[John (Taylor) Gabrowski]

That looks just like the "alligator killer" Speedmaster MC-1 that they used on the earlier Merc Twister 6 inline (1968-69??) racing engine. The Twister with the pluse tune exhaust log running down one side and green flywheel to be exact. I had one on the Twister I had, rebuilt and sold and am about to buy the second one I found here in many pieces last month that might have it if the seller can find where it is in that storage barn of his. Those units as heavy as well as heavy duty. That will be it for the only 2 Twisters that ever sold on record in this neck of the woods. :)

[largecar91]

It is a Merc MC1. Early 70's vintage. It looks like someone cut the driveshaft off!

[switzerbullet]

The driveshaft was cut off. I'm going to see if it can be squared off and add a coupling. I tried to fit it under my 150 but the water pump housing is too big. I have to make a spacer. Anyone have spacers to sell that they dont need anymore?

[Mark75H]

That's what it is. Driveshaft might have been cut esp if it was just the original Mercruiser IO stub shaft. An excellent Speedmaster to use under your 150. More than a few Speedmasters require a little grinding to the bottom of the mid section to accomodate the water pump.

[largecar91]

just grind the little tab off in the mid so the pump clears and it will bolt right up