Solenoid

[Gonzo]

Where is the solenoid located? I was told I may need a new starter solenoid.

[backfoot100]

A Ford would be someplace up near the terminal block on the rear of the engine. It would have the positive battery lead going to it and then be jumpered down to the starter. It's about 2" cubed.

A Chevy would be the small round cylinder attached to the starter itself.

What's the problems that you're having?

[Gonzo]

Sometimes when I go to start the motor, it just makes a click sound. Then I try again and it will fire up. It happens sometimes but then other times its fine.

[Midskier]

Gonz , then just the boat when it's fine and not the other times 

Like Eddie said its on the back of the engine with 2 big red cables going to it and 1 or 2 smaller wires

But while your poking around make sure all connections are snug

[Gonzo]

thanks guys, I located it and I will see what I can do.

[backfoot100]

If you have a voltmeter measure the voltage at the battery and then at the solenoid. Should very close to the same. Any significant voltage drop, start looking for loose, worn or corroded cables. There should be a smaller wire attached to the solenoid on the "S" lead. Take that off and have someone try turning the key to the start position. You should have a little over 12 volts on that wire and no volts when the key is not in the start position.
It will probably be less than the battery voltage but no more than a couple of tenths of a volt. Any more than that look for worn, loose or corroded cables between the solenoid up to the start switch and back to the solenoid again.
If it checks out with good voltage back to the solenoid, the solenoid should be replaced.