What is this Part ????

[mthieme]

I have 1978 Mercury 402 which I am attempting to restore.
A couple more things to do and I will be ready to crank her over and proceed.
But, there is a part I need to know what it is.
On the port side of the powerhead is a small blueish plastic piece about the size of an ignition capacity. It has one or two wires going to it. I can't tell as they have been cut about as close as possible.
What is this?
What does it do?

I really need to get a manual.

 

[Faztbullet]

Re: What is this Part ????

That is a mercury filled kill switch. It was to kill the engine if you hit a object and engine bracket broke and flipped up into boat.

 

[mthieme]

Re: What is this Part ????

Thanks much.
I was worried it was a show stopper as far as getting this old heap running.
(just the opposite!)
Also interesting. When I was a kid I had a 7.5 Merc of mid 70's vintage on the back of a jon boat. My friends and I would do stuff like goo over protruding sand bars and lift the motor while sliding back over to the other side and keep going.
I take it this wasn't on every model.