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Mitsubishi Diamante Engine Information
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The following technical bulletins were published by AERA.
 CYLINDER HEAD BOLT TORQUE FOR 4 & 6 G MITSUBISHI ENGINES
                             Cylinder Head Bolt Tightening Caution For
                            1992-1996 Mitsubishi 4G & 6G Series Engines

The AERA Technical Committee offers the following information regarding cylinder head bolt tightening caution on 1992-1996 Mitsubishi 4G & 6G series engines. Information previously published in the OEM service manuals was incorrect and the following specifications should be used.

Installing non-elastic head bolts use the following torque values for vehicles/engine. 

For torque sequence see Figure 1 to tighten in three steps use the bolt tightening sequence, if applicable. Refer to sequence chart. Note: Designations such as Turbo, Non-Turbo, SOHC and DOHC are only used if these items cause variations to the torque information of the engine.

Years		Models			Engine  		Torque

1992-95 		Mirage	thru May 1995	4G1 / 1.5L	53 ft/lbs (73 Nm)
1992-94 		Eclipse 			4G3 / 1.8L	53 ft/lbs (73 Nm)
1992  		Eclipse, Galant 		4G6 / 2.0L	80 ft/lbs (108 Nm) DOHC
1992		Galant, Expo & Truck	4G6 / 2.4L	80 ft/lbs (108 Nm) SOHC
1995		Galant			4G6 / 2.5L	80 ft/lbs (108 Nm) SOHC	
1992-95 		Truck, Montero, Galant	6G7 / 3.0L	80 ft/lbs (108 Nm) SOHC
		& Diamante
1993-95 		Diamante Wagon	 	6G7 / 3.0L	80 ft/lbs (108 Nm) SOHC
1992-95		Diamante & 3000 GT	6G7 / 3.5L	80 ft/lbs (108 N m) DOHC non-Turbo	
1992-95		3000 GT			6G7 / 3.0L	91 ft/lbs (123 N m) DOHC Turbo *
							* Loosen all bolts and retighten to 91 ft/lbs.
1994-95		Montero 	 		6G7 / 3.5L	80 ft/lbs (108 N m) DOHC Turbo
 
Figure 1. Cylinder Head bolt torque Sequence

Installing Elastic Head Bolts (plastic-angle tightening method).

Before reusing head bolts measure the shank lengths of ALL the head bearing bolts, if measurement of (see below) exceeded or the bolt has visual damage REPLACE THE BOLTS. Measure from the tip to the shoulder under the bolt head (not to the shoulder of the washer). See Figure 2							
1995-96		Mirage after 5/95		4G9 / 1.5L **	4.063"  (103.200 MM) 	SOHC    16Valve
1993-96		Mirage			4G9 / 1.8L ***	3.795"  (96.400 MM) 	SOHC	  8Valve
1992-95		Expo LRV		4G9 / 1.8L	3.795"  (96.400 MM) 	SOHC	  8Valve
1993-96		Eclipse			4G6 / 2.0L	3.913"  (99.400 MM)	S & D	16 Valve 1993		Galant			4G6 / 2.0L	3.913"  (99.400 MM) 	S & D	16 Valve	
1993-95 		Expo, Expo LRV & Truck	4G6 / 2.4L	4.740"  (120.400 MM)	SOHC	  8 Valve
1994-96		Galant			4G6 / 2.4L	4.740"  (120.400 MM)	SOHC	  8 Valve

Figure 2. Cylinder Head Bolt Shank Measurement
 
For torque sequence see Figure 3 to tighten elastic head bolts using the plastic/angle tightening method; the following procedure is applicable to all the engines listed below.

Step 1; Torque all bolts (in sequence) to specification 58 ft/lbs (78 Nm).  ***
Step 2, Loosen all bolts fully.
Step 3, Tighten all bolts to 14 ft/lbs (20 Nm).
Step 4, Tighten using a breaker bar (not a torque wrench) 90° rotation.
Step 5, Repeat step four.

Note: ** For the 1995-96 Mirage after 5/95 initial torque is a lower value Step one Torque all bolts (in sequence) to specification 34 ft/lbs (49 Nm).
         *** For the 1993-96 Mirage & 1992-95 Expo LRV initial torque is a lower value Step one Torque all bolts (in sequence) to specification 54 ft/lbs (74 Nm).

Figure 2. Cylinder Head Bolt Shank Measurement

 Figure 3. Cylinder Head Bolt Torque Sequence.
                                                                       The AERA Technical Committee
 MAIN BEARING BOLT TORQUE CAUTION ON MITSUBISHI 4/6 G ENGINES
                                           Main Bolt Tightening Caution For
                                  1992-1999 Mitsubishi 4G & 6G Series Engines

The AERA Technical Committee offers the following information for main bolt tightening caution on 1992-1995 Mitsubishi 4G & 6G series engines. Information previously published in the OEM service manuals was incorrect and the following specifications should be used. The information in TB 2039 has abeen  updated and it should be destroyed, as it is no longer valid information.

To install non-elastic main bearing bolts, the following procedure is applicable to all vehicles/engine listed below.

Tighten the bolts on each main bearing cap equally until the specified torque is achieved. Use the bolt-tightening sequence shown in Figure 1 if applicable.

 
Years                Models                     Engine                  Torque

1992-95            Mirage                       4G1/1.5L          38 ft/lbs (53 Nm)
1992-94            Eclipse                      4G3/1.8L          38 ft/lbs (53 Nm)
1992        Galant, Expo & Truck        4G6/2.0&2.4L  38 ft/lbs (53 Nm) SOHC
1992         Eclipse, Galant                 4G6/2.0L          49 ft/lbs (68 Nm) DOHC
1992-95  Truck,Montero,Galant,
               Diamante                             6G7/3.0L         57 ft/lbs (79 Nm) SOHC
1993-95 Diamante Wagon                6G7/3.0L          57 ft/lbs (79 Nm) SOHC
1992-95 Diamante & 3000 GT           6G7/3.0L         67 ft/lbs (93 Nm) DOHC  Non/Turbo
1992        3000 GT                              6G7/3.0L          67 ft/lbs (93 Nm) DOHC Turbo
1993-95   3000 GT                              6G7/3.0L          54 ft/lbs (74 Nm) DOHC Turbo
1994-95   Montero                              6G7/3.5L          54 ft/lbs (74 Nm) DOHC Turbo
 
Elastic main bolt tightening (plastic-angle tightening method). Before reusing main bolts measure the shank lengths of ALL the main bearing bolts. If the measurement of 2.799 (71.100 MM) is exceeded or the bolt has visual damage REPLACE THE BOLTS. Measure from the tip to the shoulder under the bolt head (not to the shoulder of the washer) see figure 3.

To tighten elastic main bearing bolts using the plastic/angle tightening method; the following procedure is applicable to all the engines listed below.

1. Torque bolts (in sequence see figure 2) to specification 18 ft/lbs.
2. Using a breaker bar (not a torque wrench), tighten each bolt 90°.
3. Using a breaker bar (not a torque wrench), turn each bolt an additional 90°.

The following vehicles/engines use elastic main bearing bolts:

1993-95          Mirage               4G9/1.8L         18 ft/lbs (25 Nm) Plus 90°, +90° 
1992-95          Expo LRV          4G9/1.8L         18 ft/lbs (25 Nm) Plus 90°, +90°
1993-95          Eclipse              4G6/2.0L         18 ft/lbs (25 Nm) Plus 90°, +90°
1993               Galant                4G6/2.0L         18 ft/lbs (25 Nm) Plus 90°, +90°
1993-95    Expo, Expo LRV, 
                 Truck                        4G6/2.4L          18 ft/lbs (25 Nm) Plus 90°, +90°
1994-95         Galant                 4G6/2.4L          18 ft/lbs (25 Nm) Plus 90°, +90°
 
                                                                          The AERA Technical Committee
 CONNECTING ROD NUT TORQUE CAUTION
                                        Connecting Rod Nut Tightening Caution On
                                    1992-1995 Mitsubishi 4G Series & 6G7 Engines

The AERA Technical Committee offers the following information for connecting rod nut tightening caution on 1992-1995 Mitsubishi 4G Series & 6G7 engines. Information previously published in service manuals was incorrect and the following specifications should be used.

Years        Models                      Engine                          Torque

1992-95     Mirage                       4G1                          14 FT/LBS (20 Nm) plus 90°

1992-94     Eclipse                      4G3                          25 FT/LBS (34 Nm)

1992    Eclipse, Galant, Mirage 4G6                          38 FT/LBS (52 Nm)
                  Expo & Truck

1993-95 Eclipse, Galant, Mirage 4G6                        14 FT/LBS (20 Nm) plus 90°
                Expo LRV and Truck

1993-95    Mirage                          4G9                         14 FT/LBS (20 Nm) plus 90°
1992-95    Expo LRV 

1992-96 Truck, Diamante (wagon)  6G72                    38 FT/LBS  
               3000 GT, Montero & Galant

1992-95 Truck, Diamante (wagon)  6G74                    25 FT/LBS (34 Nm) plus 90°
               3000 GT, Montero & Galant

Note: If the above listed specifications are not used, engine failure may occur.

                                                                         The AERA Technical Committee