LCD erased after communication ethernet bgin

Hi good night people,
I have a problem with my sketch and my LCD, if i put this two lines the information after this is not displayed, only before start the ethernet communication for example "proyecto" and "dimmer for bulb" its showed but the next strings are not displayed after the delay what im doing wrong?.

Thanks.

Ethernet.begin(mac, ip);
server.begin();

#include <LiquidCrystal.h>
#include <TimerOne.h>        
#include <SPI.h>
#include <EthernetV2_0.h>
#define W5200_CS  10
#define SDCARD_CS 4

LiquidCrystal lcd(13,12,11,10,9,8);
volatile int i=0;               // Variable to use as a counter
volatile boolean zero_cross=0;  // Boolean to store a "switch" to tell us if we have crossed zero
int AC_pin = 3;                 // Output to Opto Triac
int dim2 = 0;                   // led control
int dim = 128;                  // Dimming level (0-128)  0 = on, 128 = 0ff
int pas = 8;                    // step for count;
int freqStep = 75;    // This is the delay-per-brightness step in microseconds.
String readString = String(30);  // tamaño de string para buscar las direcciones establecidas(Ligarled,Desligarled)

byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };   // Escribimos la direccion MAC de el Ethernet Shield
byte ip[] = { 192, 168, 1, 2 };                       // Escribimos la IP dentro del rango de la red
EthernetServer server(80);                           // Iniciamos el puerto de servicio

 
void setup() {  // Begin setup
  Serial.begin(9600);
  pinMode(AC_pin, OUTPUT);      // Set the Triac pin as output
  digitalWrite(SDCARD_CS,HIGH);//Deselect the SD card
  pinMode(SDCARD_CS,OUTPUT);
  attachInterrupt(0, zero_cross_detect, RISING);    // Attach an Interupt to Pin 2 (interupt 0) for Zero Cross Detection
  Timer1.initialize(freqStep);                      // Initialize TimerOne library for the freq we need
  Timer1.attachInterrupt(dim_check, freqStep);      // Use the TimerOne Library to attach an interrupt

 lcd.begin(16, 2); // set up the LCD's number of columns and rows: 
 lcd.clear(); // clear the screen
 lcd.setCursor(2, 0); // put cursor at colon 0 and row 0
 lcd.print("Proyecto"); // print a text
 lcd.setCursor(0, 1); // put cursor at colon 0 and row 1
 lcd.print("dimmer for bulb"); // print a text
 delay (4000);
 lcd.clear(); // clear the screen
Ethernet.begin(mac, ip);
 server.begin();

}

void zero_cross_detect() {    
  zero_cross = true;               // set the boolean to true to tell our dimming function that a zero cross has occured
  i=0;
  digitalWrite(AC_pin, LOW);
}                                 

// Turn on the TRIAC at the appropriate time
void dim_check() {                   
  if(zero_cross == true) {              
    if(i>=dim) {                     
      digitalWrite(AC_pin, HIGH);  // turn on light       
      i=0;  // reset time step counter                         
      zero_cross=false;    // reset zero cross detection
    } 
    else {
      i++;  // increment time step counter                     
    }                                
  }    
}                                      

void loop() {  

  Serial.print("dim=");
  Serial.print(dim);

  Serial.print("     dim2=");
  Serial.print(dim2);
  Serial.print("     dim1=");
  Serial.print(2*dim);
  Serial.print('\n');
  delay (100);
 lcd.setCursor(2, 0); // put cursor at colon 0 and row 0
 lcd.print("power is "); // print a text
 lcd.print(100-100*(255-dim2)/255);
 lcd.print("%    "); // print a text
 lcd.setCursor(1, 1); // put cursor at colon 0 and row 1
 lcd.print("dim. level="); // print a text
 lcd.print(dim);
 lcd.print("  "); // print a text
}
LiquidCrystal lcd(13,12,11,10,9,8);

You are connecting your LCD to the SPI pins. They are used for communication between the Arduino and the Ethernet shield. They are NOT available for you to use.