Re: 1979 Mercury side mount control how to operate
Bob, there are various different styles and a pic or description of the box would help narrow it down.
In general, you've got a relatively 'square' box with a single-lever control for all shifting/throttle action. This type of box has a lever at the back for fast idle, raise it up for starting and lower before putting in gear, just like your typical OMC box. This box will have a rubber-covered pushbutton for choke, which is engaged only when you push the button.
Newer style boxes have a shift interlock in the end of the handle where you rest your hand; you have to push or pull on it with your fingers as you're shifting into gear.
This type of box may have a button at the pivot point of the handle; if so, for fast idle push inwards on the button and move the control lever fwd for throttle only. Once you pull back to Neutral the button will pop back out and you'll be able to shift into gear. This control box will probably have the choke in the key switch, push-to-choke, which is engaged as long as you hold the key in.
Other styles of box may not have a fast-idle button to push or any other obvious means of fast idle. On this box you'd pull the control lever towards you to get into fast-idle mode. With the lever pulled out you'll get only throttle action. Return to the Neutral position and push the lever inwards to re-engage shifting action.
Well, this should just about cover the most commonly-used types, one of the above should 'click'. Let us know if you have any other questions.
HTH............ed