Chevrolet Full Size Cars 1979-1989

Rochester M4ME and E4ME 4-BBL Carburetors

Print



Click image to see an enlarged view

Fig. Fig. 1 Choke rod fast idle cam adjustment 1983-88 E4ME



Click image to see an enlarged view

Fig. Fig. 2 Unloader adjustment 1983-88 E4ME

Float, pump, choke coil lever, fast idle, fast idle cam (choke rod), front and rear vacuum breaks and the unloader adjustments on these two carburetors are identical to those detailed in the preceding M2ME and E2ME section. Please refer to them. There are, however, a number of procedures that apply only to the 4-bbl carburetors and to specific years. Please refer to the appropriate procedure or illustration.

AIR VALVE ROD ADJUSTMENT





Click image to see an enlarged view

Fig. Fig. 3 Adjusting the air valve rod M4ME and E4ME (through 1982)



Click image to see an enlarged view

Fig. Fig. 4 Adjusting the air valve rod 1983-85 M4ME and E4ME



Click image to see an enlarged view

Fig. Fig. 5 Adjusting the air valve rod 1986-88 M4ME and E4ME

  1. Using an outside vacuum source, seat the choke vacuum diaphragm. Put a piece of tape over the purge bleed hole if so equipped.
  2.  
  3. Close the air valve completely.
  4.  
  5. Insert the gauge between the rod and the end of the slot in the lever.
  6.  
  7. Bend the rod to adjust the clearance.
  8.  

SECONDARY LOCKOUT ADJUSTMENT





Click image to see an enlarged view

Fig. Fig. 6 Secondary lockout adjustment M4ME and E4ME

  1. Pull the choke wide open by pushing out on the choke lever.
  2.  
  3. Open the throttle until the end of the secondary actuating lever is opposite the toe of the lockout lever.
  4.  
  5. Measure the clearance between the lockout lever and the secondary lever.
  6.  
  7. Bend the lockout pin until the clearance is in accordance with the proper specifications.
  8.  

SECONDARY CLOSING ADJUSTMENT





Click image to see an enlarged view

Fig. Fig. 7 Secondary closing adjustment M4ME and E4ME

  1. Make sure that the idle speed is set to the proper specifications.
  2.  
  3. The choke valve should be wide open with the cam follower off of the steps of the fast idle cam.
  4.  
  5. There should be 0.020 in. (0.508mm) clearance between the secondary throttle actuating rod and the front of the slot on the secondary throttle lever with the closing tang on the throttle lever resting against the actuating lever.
  6.  
  7. To adjust, bend the secondary closing tang on the primary throttle actuating rod.
  8.  

SECONDARY OPENING ADJUSTMENT





Click image to see an enlarged view

Fig. Fig. 8 Secondary opening adjustment M4ME and E4ME

  1. Open the primary throttle valves until the actuating link contacts the upper tang on the secondary lever.
  2.  
  3. With the two point linkage, the bottom of the link should be in the center of the secondary lever slot.
  4.  
  5. With the three point linkage, there should be 0.070 in. (1.778mm) clearance between the link and the middle tang.
  6.  
  7. To adjust, bend the upper tang on the secondary lever.
  8.  

AIR VALVE SPRING ADJUSTMENT





Click image to see an enlarged view

Fig. Fig. 9 Adjusting the air valve spring M4ME and E4ME

To adjust the air valve spring windup, loosen the Allen lockscrew, then turn the adjusting screw counterclockwise so as to remove all spring tension. With the air valve closed, turn the adjusting screw clockwise the specified number of turns after the torsion spring contacts the pin on the shaft. Hold the adjusting screw in this position and tighten the lockscrew.

 
label.common.footer.alt.autozoneLogo