I've discovered something about my Torqeedo outboard (model 1003), the hard way..... On Monday, when leaving the festival harbor in Port Townsend, I was running out through the entrance and suddenly lost nearly all propulsion. This was quite unfortunate because there was a good breeze in my face and a barnacle encrusted jetty to our lee. Emily Ruth suffered mostly cosmetic damage after banging a couple of times before I could paddle us, then sail us, back into the harbor. I think that I was more the worse for wear but only psychologically.

Yesterday I dug into the motor to fully determine the failure and, as I had suspected, the culprit turned out to be the shear pin. For those of you with Torqeedos and who have never removed the prop, please heed this advice: Take the prop off now and examine the shear pin. As provided by the manufacturer, it appears to be carbon steel. It rusts. The broken pin ruptured the surrounding plastic recess:

Torqeedo, broken prop - 1.jpg

You can see the broken pin intruding into the adjacent plastic cell at about the the 4 to 5 o'clock position. Also note the rust deposits within the slot that holds the pin.

An examination of the pin using a magnifying lens seems to indicate that it has been, at least, partially ruptured for some time. So a final failure was inevitable.

The owners manual cautions one to rinse the motor with fresh water after use. This is a difficult task for me to accomplish as my motor resides on the boat which is on a mooring. Additionally, a surface rinse will not flush out the salt water from inside the prop where the shear pin is located. Only dunking it into a bucket of water would help.

I'm left with lots of questions and uncertainty. I wonder if shear pins on outboard motors are usually made of material that will rust. That seems like a poor choice when I'm sure there are other materials more suited for the purpose. My internet searching has revealed no alternative to the Torqeedo supplied pins, so I guess I'm stuck with them. Using something I make myself would be a foolhardy, I think, since I don't know what sort of forces are at work and could damage the motor and gears. So my plan for now is to embark on a proactive maintenance schedule:

I'll certainly change the pins out at the beginning of each season
I will apply a good dollop of marine waterproof grease when installing the shear pin.
Rinse whenever I can, and throughly by removing the prop.

If anyone has had a similar experience and has found solutions I'd very much appreciate hearing about them.