Lightwin/Ducktwin Lower Unit

[Mumbles]

If the crank and driveshaft splines are rusted away, you can always do the ‘weld/silver braze a socket on’ trick to get the motor going again until proper replacement parts can be located. This also requires shortening the shaft and filing a hex on the end to fit the socket. With only three horse max being generated, this band aid fix should last for some time.

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[outboard315]

That seems like a lot of work for some fairly inexpensive parts. Just my thoughts.

[outbdnut2]

Lotsa those motors around – post a Wanted ad on our classified board – somebody will have what you need from a parts motor – but first, of course, take it apart and verify the problem. I’ve got a couple parts motors like that but I can’t get to them until spring – too much stuff packed in front of them for the winter.
Dave

[david-bartlett]

quote Outboard315:

That seems like a lot of work for some fairly inexpensive parts. Just my thoughts.

I can see your point, however if this were a different, less common motor, this method might well be worth doing.

But if I had all of Mumbles cool toys and talent, I would do it just for fun.

[captchuck]

Well Gary, I stand bowed and bloody. Looks like you have plenty of suggestions when you finally get back to where the engine is.

[loggerhead]

Finally picked up the little Ducktwin and fixed her up a nice cozy spot in the garage, pulled the L/U and surprise! OK Frank, who has my driveshaft? 🙄 Upper W/P housing and impeller are missing too but got the parts located. As near as I can tell, the driveshaft splines look good so thinking maybe “a” P/O removed the shaft to replace the impeller and all the parts just vanished. The guy I got it from didn’t have any history on the motor so I’ll sort it all out eventually. The front of the fuel tank had the usual dock impact damage but I was able to remove the dents by pressurizing the tank and applying oxy/acetylene heat. Thanks to all for your input and replies, it led to some interesting fixes for future projects if ever needed.

[garry-in-michigan]

The driveshaft is stainless steel and virtually indestructible. The crankshaft on the other hand is forged steel with the bearing areas case hardened. In order to keep the crankshaft splines from rusting they are lightly coated with grease and a neoprene "O" ring on groove in the spline is supposed to keep the grease in and the water out. In replacing the water pump you should always check to see the "O"ring has not been nicked by the edges of the spline and that there is a grease film on the splines. Be aware too much grease may cause a hydrostatic lock which makes it impossible to install the lower unit. In this case, the extra grease will have to be removed. Shortening the drive shaft in NOT an option . . . 😆

In other words the pinion gear, or the driveshaft and pinion gear may be missing . . . 🙁

[garry-in-michigan]

The 277214 gear set is no longer avaisable. Used gears are. Being they were machined as a set, another pinion may introduce a bit of a gear wine. Usually this only bothers the fish . . . 😆

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