Soriano du Puy (and more), Deutsches Museum (Munich)

[Smokin' Joe]

Wayne, I think you're right, counter rotating props

http://www.soriano-outboard.com/11357.html

with rear prop on backward in the photo! I took inventory in our Houston garage in fall. I have enough parts to build (more than) a complete 3 cyl. 75 powerhead, ready to bolt onto a downhousing and run. Got enough gearcase parts to build multiple gearcases, minus housing and driveshaft. So I'm buying a downhousing and gearcase housing with driveshaft to put together a motor (need to find an Evinrude 75 cowl) . I haven't the foggiest idea what I'll do with it afterward. Maybe just put it on a stand and look at it, like your König. I simply love the old outboards.

Best,
Joe

Great pics and info Joe. I probably read the answer to my question before when info on the Soriano was posted, and I am guessing the rear lower unit shaft operated in left hand rotation....correct? I understand what you are saying about running in the wake of the leading prop and agree about the hydrodynamics. Also surfacing props at high speeds don't churn up the water as badly as a fishing motor, and I guess they proved it would work just fine. But my second question is....they didn't run that prop backwards like in the pic did they? I'm guessing someone at the museum just put it on as a mirror image of the leading prop, because I can't see how it would work that way at all. Or am I missing something?

[Smokin' Joe]

Charley, I just replied to Wayne about that. What motor is that in your photo?!!

Joe

I noticed that the rear prop is on backwards, too. My Dad used to tell me stories about these engines and how strong they were. The front prop is made for fitting to the front of the lower unit. Someone might have just stuck a prop on for display.

[F-12]

Dad told me of these units and they were solid drive shaft supported on both end with a single pinion. If they are run in this position it will turn up big rpms and go nowhere.
The engine in my signature is a 44 Quincy Flathead. This is the one that made my DOH Aerowing feel like it was about 3 feet too short.

[Smokin' Joe]

The torn down gearcase in

http://www.soriano-outboard.com/11357.html

looks like 2 separate prop shafts.

Joe

Dad told me of these units and they were solid drive shaft supported on both end with a single pinion. If they are run in this position it will turn up big rpms and go nowhere.
The engine in my signature is a 44 Quincy Flathead. This is the one that made my DOH Aerowing feel like it was about 3 feet too short.

[F-12]

I guess the engine changed over the short time they were raced. My Dad's stories started in 1929-30 and he was out after WW2 broke out. Seems to me it would still be reversed as far as the rear prop.

[Smokin' Joe]

Had I really looked then I'd have seen the Mercury crankcase, if not the timing belt.

Dad told me of these units and they were solid drive shaft supported on both end with a single pinion. If they are run in this position it will turn up big rpms and go nowhere.
The engine in my signature is a 44 Quincy Flathead. This is the one that made my DOH Aerowing feel like it was about 3 feet too short.

[Master Oil Racing Team]

Yeah, Joe & Charley....the photos show it like I expected. Right hand prop in front, left hand prop in the rear, with the leading edge of the blades facing forward. Somebody either just stuck that prop on the lower unit at the museum without paying attention, or didn't know how it went and tried to make a mirror image, or just maybe playing a joke. Two separate counter rotating prop shafts and it would just need the one drive shaft to make that work. You could swap prop shafts, but not props. Somebody probably "borrowed" the left hand prop that was originally on the motor. It was hard to tell if those brass props had tapered hubs, but it didn't look like they did. Maybe the one at the museum was for kilo runs.

[Mark75H]

A single drive shaft drives 2 prop shafts, a front shaft and a back shaft, running counter rotation to each other ... like the Volvo and Mercruiser stuff in modern times

These motors dominated D and then X class racing from the late 1920's until the early 1950's ... they were not a flash in the pan.