CS0029 convert type

Hi

I am trying to change the color of my gameobject called p911 to specific colors by pushing buttons that I defined them in script, but I get the error that cannot convert string to bool. if anyone that can help I would appreciate it.
if there are any problems in my other parts of code, please tell me.

thank you.

public class ChangeColor : MonoBehaviour {

private GameObject P911 = new GameObject();
private GameObject turnred = new GameObject();
private GameObject turnblack = new GameObject ();
private GameObject turnwhite = new GameObject ();
private GameObject turnyellow = new GameObject ();
// Use this for initialization
void Start () {
	GameObject.Find ("P911").renderer.enabled = true;
	GameObject.Find ("turn-red").renderer.enabled = true;
	GameObject.Find ("turn-black").renderer.enabled = true;
	GameObject.Find ("turn-white").renderer.enabled = true;
	GameObject.Find ("turn-yellow").renderer.enabled = true;

	P911 = GameObject.Find ("P911");
	turnred = GameObject.Find ("turn-red");
	turnblack = GameObject.Find ("turn-black");
	turnwhite = GameObject.Find ("turn-whit");
	turnyellow = GameObject.Find ("turn-yellow");

}

void OnMouseDown ()
{

	//P911.gameObject.renderer.material.color = new Color (r, g, b, a);
	gameObject.renderer.material.color = new Color (11,22,33,123);
	if ("turn-red") {
					P911.renderer.material.color = new Color (232, 0, 0, 255);
			} else if ("turn-black") {
					P911.renderer.material.color = new Color (0, 0, 0, 255);
			} else if ("turn-white") {
					P911.renderer.material.color = new Color (184, 184, 184, 255);
			} else if ("turn-yellow") {
					P911.renderer.material.color = new Color (201, 187, 0, 255);
			}
}

}

Your ifs should be using the variable, not the literal string. As follows.

if (turnred) {
    P911.renderer.material.color = new Color (232, 0, 0, 255);
} else if (turnblack) {
    P911.renderer.material.color = new Color (0, 0, 0, 255);
} else if (turnwhite) {
    P911.renderer.material.color = new Color (184, 184, 184, 255);
} else if (turnyellow) {
    P911.renderer.material.color = new Color (201, 187, 0, 255);
}

This will fix the error, but not sure if it will behave how you intend.