subroutine with if else does not work

Question

Everything in this code seems to work as expected except the subroutine speedcw at the bottom. It should change the time_delay variable.

#define ENA 2 //pin 2 on chip
#define in_A 0 //pin 0 on chip IN2
#define in_B 1 //pin 1 on chip IN1
#define in_C 3 //pin 3 on chip AUX
#define in_D 4 //pin 4 on chip AUX

byte PWM_PIN = 5;  //pin 5 on chip

int pwm_value = 1500;

int time_delay = 7;

void setup() {
    pinMode(ENA, OUTPUT);
    pinMode(in_A, OUTPUT);
    pinMode(in_B, OUTPUT);
    pinMode(in_C, OUTPUT);
    pinMode(in_D, OUTPUT);
    pinMode(PWM_PIN, INPUT);
}

void step1(){
    //A+,B+
    digitalWrite(in_A, 1);
    digitalWrite(in_B, 1);
    delay(time_delay);
}

void step2(){
    //A+,B-
    digitalWrite(in_A, 1);
    digitalWrite(in_B, 0);
    delay(time_delay);
}

void step3(){
    //A-,B-
    digitalWrite(in_A, 0);
    digitalWrite(in_B, 0);
    delay(time_delay);
}

void step4(){
    //A-,B+
    digitalWrite(in_A, 0);
    digitalWrite(in_B, 1);
    delay(time_delay);
}

void clockwise(long st){
    long i = 0;
    while( i < st ){
        //step1
        step1();
        //step2
        step2();
        //step3
        step3();
        //step4
        step4();
        i++;
    }
}

void counter_clockwise(long st){
    long i = 0;
    while( i < st ){
        //step1
        step4();
        //step4
        step3();
        //step3
        step2();
        //step2
        step1();
        i++;
    }
}

void loop() {
    pwm_value = pulseIn(PWM_PIN, HIGH);
    time_delay = 7;

    while (pwm_value <= 1450) {//red LED
        pwm_value = pulseIn(PWM_PIN, HIGH);
        digitalWrite(ENA, 1);
        //    digitalWrite(in_C, 1); //red LED
        //    digitalWrite(in_D, 0); //green LED
        // time_delay = 1;
        speedcw();
        clockwise(2);
    }

    while (pwm_value >= 1550) {//green LED
        pwm_value = pulseIn(PWM_PIN, HIGH);
        digitalWrite(ENA, 1);
        //    digitalWrite(in_C, 0); //red LED
        //    digitalWrite(in_D, 1); //green LED
        time_delay = 1;
        // speedccw();
        counter_clockwise(2);
    }

    while ((pwm_value >= 1451)&&(pwm_value <= 1549)) {
        pwm_value = pulseIn(PWM_PIN, HIGH);
        digitalWrite(ENA, 0);
        digitalWrite(in_C, 0);
        digitalWrite(in_D, 0);
    }
}

void speedcw(){
    if (pwm_value <= 900){
        time_delay = 1;
    }
    else if (pwm_value <= 1000){
        time_delay = 2;
    }
    else if (pwm_value <= 1100){
        time_delay = 3;
    }
    else if (pwm_value <= 1200){
        time_delay = 4;
    }
    else if (pwm_value <= 1300){
        time_delay = 5;
    }
    else if (pwm_value <= 1400){
        time_delay = 6;
    }
}

void speedccw(){
}