Oil Pump

Removal & Installation

2.4L Engine

To Remove:

1. Remove the drain plug and gasket.
2. Remove the oil filter.
3. Remove the Oil Pan.
4. Remove the baffle plate.
5. Remove the oil screen and oil screen gasket.
6. Remove the relief plug.
7. Remove the gasket.
8. Remove the relief spring.
9. Remove the relief plunger.
10. Remove the oil filter bracket.
11. Remove the oil filter bracket gasket.
12. To remove the plug, do the following:
    • Step 1: Align the plug wrench (special tool #MD998162) with the notch.
    • Step 2: Place the plug wrench retainer (special tool #MD998783) and push it lightly. Put the washer on to fit the clearance between the plug retainer and the housing.

      CAUTION
      Be careful not to loosen the plug cap too much because the oil pump shaft will be bent by excessive force.

    • Step 3: Loosen the plug cap a bit and remove the plug wrench (special tool #MD998162).
    • Step 4: Remove the plug cap.
13. Remove the O-ring.
14. When removing the flange bolt, do the following:
    • Step 1: Remove the plug on the side of the cylinder block.
    • Step 2: Insert a Phillips screwdriver (shank diameter 0.3 in [8 mm]) into the plug hole to lock the counterbalance shaft.
    • Step 3: Loosen the flange bolt.
15. Remove the front case and front case gasket.
16. Remove the oil pump cover.
17. Remove the oil pump driven gear.
18. Remove the oil pump drive gear.
19. Remove the crankshaft front oil seal.
20. Remove the oil pump oil seal.
21. Remove the counterbalance shaft oil seal.
22. Remove the counterbalance shafts (left) and (right).
23. To remove the counterbalance shaft (front bearing), use the silent shaft bearing puller (special tool #MD998371) to remove the counterbalance shaft front bearing from the cylinder block.

    CAUTION
    Remove the front bearing first. If it has not been removed, use a silent shaft bearing puller (special tool #MD998372) cannot be used for rear balance shaft bearing removal.

24. To remove the counterbalance shaft (rear bearing) (right) and the counterbalance shaft (rear bearing) (left), install a bearing installer stopper (special tools #MB991603) and silent shaft bearing puller (special tool #MD998372). Next use the silent shaft bearing puller to remove the right counterbalance shaft rear bearing from the cylinder block.

To Install:

1. To install the counterbalance shaft (rear bearing) (left), do the following:
   • Step 1: Install the bearing installer stopper (special tool #MB991603) to the cylinder block.
   • Step 2: Apply the engine oil to the rear bearing outer surface and bearing hole the cylinder block.
   • Step 3: Use a silent shaft bearing installer (special tool #MD998705) to install the rear bearing.

   NOTE: The left rear bearing has no oil holes.

2. To install the counterbalance shaft (rear bearing) (right), do the following:
   • Step 1: Install the guide pin of the silent shaft bearing installer (special tool #MD998705) in the threaded hole of the cylinder block as shown.
   • Step 2: Align the ratchet ball of the silent shaft bearing installer with the oil hole in the rear bearing to install the bearing of the silent shaft bearing installer.
   • Step 3: Apply clean engine oil to the bearing outer surface and bearing hole in the cylinder block.
   • Step 4: Using the silent shaft bearing installer, install the rear bearing, then make sure that the oil hole of the bearing is aligned with the oil hole of the cylinder block.
3. To install the counterbalance shaft (front bearing), do the following:
   • Step 1: Remove the rear bearing installing portion from the silent shaft bearing installer (special tool #MD998705).
   • Step 2: Install the guide pin of the silent shaft bearing installer into the threaded hole of the cylinder block.
   • Step 3: Align the ratchet ball of the silent shaft bearing installer with the oil hole in the rear bearing to install the bearing of the silent shaft bearing installer.
   • Step 4: Apply clean engine oil to the front bearing outer surface and bearing hole in the cylinder.
   • Step 5: Use the silent shaft bearing installer to install the rear bearing. Be certain that the oil hole of the bearing is aligned with the oil hole of the cylinder block.
4. Remove the counterbalance shafts (right) and (left).
5. Use a socket wrench to install the counterbalance shaft oil seal into the front case.
6. Use a socket wrench to install the oil pump oil seal onto the front case.
7. Use a crankshaft front oil seal installer (special tool #MD998375) to install the crankcase front oil seal onto the front case.
8. When installing the oil pump drive gear and the oil pump driven gear, install them onto the front case and line up the alignment marks.
9. Install the oil pump cover.
10. Install the front case gasket and the front case.
11. To install the flange bolt, do the following:
    • Step 1: Place a crankshaft front oil seal guide (special tool #MD998285) onto the front end of the crankshaft and apply a thin coating of clean engine oil onto the outer surface of the crankshaft front oil seal guide.
    • Step 2: Put clean engine oil onto the lip of the crankshaft front oil seal.

      CAUTION
      When installing the tightening bolts, carefully note their different lengths and install into the correct places.

    • Step 3: Install the front case gently to avoid damaging the oil seal.
    • Step 4: Tighten all of the flange bolts to 17 ft-lbs (23 Nm).
12. Install the O-ring.
13. When installing the plug, do the following:
    • Step 1: Insert a Phillips head screwdriver (shank diameter 0.3 in [8 mm]) into the hole in the left side of the cylinder block to lock the counterbalance shaft.
    • Step 2: Tighten the flange bolt to 27 ft-lbs (36 Nm) to secure the oil pump driven gear onto the left counterbalance shaft.
    • Step 3: Pull out the screwdriver and screw in the plug.
14. Install the oil filter bracket gasket.
15. To install the oil filter bracket, do the following:
    • Step 1: Install the new O-ring onto the oil pump case.
    • Step 2: Lightly hand-tighten the plug cap.
    • Step 3: Put the plug wrench retainer (special tool #MD998783) onto the plug cap notch.
    • Step 4: Correctly place the plug wrench retainer, lightly pushing it. Put the washer in place to fit the clearance between the plug wrench retainer and the housing.

      CAUTION
      The clearance between the plug wrench retainer and the housing should fit, otherwise the oil pump shaft will be bent by excessive force.

    • Step 5: Tighten the plug cap to 17 ft-lbs (23 Nm).
16. Install the relief plunger.
17. Install the relief spring.
18. Install the gasket.
19. Install the relief plug.
20. Install the oil screen gasket and the oil screen.
21. Install the baffle plate.
22. To install the oil pan, do the following:
    • Step 1: Clean both gasket surfaces of the oil pan and cylinder block.
    • Step 2: Apply a 0.15 in (4 mm) diameter bead of sealant to the flange of the oil pan. Use Mitsubishi Genuine Part #MD970389.
    • Step 3: Install the oil pump case assembly to the front side of the cylinder block.

      NOTE: Make sure you install the oil pan within 15 minutes while the sealant is still wet.

    • Step 4: Fit a 0.30 in (8 mm) bolt into each of the two holes identified by the letter "S" in the illustration, and fit a 0.39 in (10 mm) bolt in each of the remaining 17 holes. Tighten all bolts to 80 in-lbs (9.0 Nm).

    NOTE: Wait for one hour after installing to allow the sealant to dry. During this time, keep oil away from the area.

23. To install the oil filter, do the following:
    • Step 1: Clean the installation surface of the filter bracket.
    • Step 2: Apply clean engine oil to the O-ring of the oil filter.
    • Step 3: Using a general service tool, install the oil filter to the bracket and tighten it to the specified torque.
24. Part #MD356000 filter: 124 in-lb (14 Nm)
25. Other Mitsubishi genuine filters: 13 ft-lbs (17 Nm)
26. If a torque wrench cannot be used, do the following:
27. Screw in the oil filter until its O-ring contacts the oil filter bracket.
28. Tighten the oil filter accordingly:
29. Part #MD356000 filter: one turn
30. Other Mitsubishi genuine filters: ¾ turn
31. Install the drain plug gasket.

    CAUTION
    Be sure to install the drain plug gasket in the correct direction because if it is installed in the wrong direction, the result will be oil leaks.

32. Install the drain plug.

3.8L Engine

To Remove:

1. Remove the drain plug.
2. Remove the drain plug gasket.

   CAUTION
   When removing the lower oil pan, do not use any type of scraping tool.

3. Remove the lower oil pan mounting bolts, then remove the lower oil pan by holding a wooden plank against the side of the pan and tapping the wood with a plastic mallet.
4. Remove the cover.
5. To remove the upper oil pan, do the following:
   • Step 1: First, remove the long bolts marked "Z" as shown.

     Oil pan bolt removal (3.8L)

   • Step 2: Remove all of the other bolts.

     CAUTION
     When removing the upper oil pan, do not use any type of scraping tool.

   • Step 3: Remove the oil pan.
   • Step 4: Screw in the M10 bolts into the 2 bolt holes in the oil pan to break the joint and remove the oil pan.
6. Remove the vertical baffle plate.
7. Remove the oil screen and gasket.
8. Remove the horizontal baffle plate.
9. Use an oil pressure switch socket wrench (special tool #MD998012) to remove the engine oil pressure switch.
10. Remove the oil filter cover.
11. Remove the oil filter.
12. Remove the oil filter bracket and gasket.
13. Remove the relief plug.
14. Remove the relief spring.
15. Remove the relief plunger.
16. Remove the crankshaft front oil seal.
17. Remove the oil pump case assembly.
18. Remove the O-ring.
19. Remove the oil pump cover.
20. Before removing the oil pump outer and inner rotor, make alignment marks on the outer and inner rotors for correct installation later.
21. Remove the oil pump case.

To Install:

1. Install the oil pump case.
2. Before installing the oil pump inner and outer rotors, apply clean engine oil to the rotors. When installing the rotors, line up the alignment marks made during removal.
3. Install the oil pump cover.
4. Install the O-ring.
5. To install the oil pump case assembly, do the following:
   • Step 1: Clean the gasket mating surfaces of oil pump case and cylinder block.
   • Step 2: Apply a 0.1 in (3 mm) diameter bead of sealant to the oil pump case. Use Mitsubishi genuine part #MD970389. When applying the sealant, the grooves must be traced and the bolt holes must be surrounded with a bead of sealant.
   • Step 3: Install the oil pump case assembly onto the front of the cylinder block.

     NOTE: Make sure you install the oil pan case within 15 minutes while the sealant is still wet.

   • Step 4: Tighten the oil pump case mounting bolts to 122 in-lbs (14 Nm).

   NOTE: Wait for one hour after installing to allow the sealant to dry. During this time, keep oil and coolant away from the area.

6. To install the crankshaft front oil seal, do the following:
   • Step 1: Install the guide of crankshaft front oil seal installer (special tool #MD998717) to the front end of the crankshaft.
   • Step 2: Apply engine oil to the lip area of a new oil seal and push it in until it contacts the oil pump case.
   • Step 3: Using the crankshaft front oil seal installer, press-fit the oil seal into the oil pump case.
7. Install the relief plunger.
8. Install the relief spring.
9. Install the relief plug.
10. Install the oil filter bracket gasket and oil filter bracket.
11. To install the oil filter, do the following:
    • Step 1: Clean the installation surface of the filter bracket.
    • Step 2: Apply engine oil to the O-ring of the oil filter.
    • Step 3: Install the oil filter to the bracket and tighten it to 122 in-lbs (14 Nm).
    • Step 4: In the event you cannot use a torque wrench for tightening, do the following:
12. Screw in the oil filter until the O-ring comes into contact with the oil filter bracket.
13. Tighten the oil filter 1 turn.
14. Install the oil filter cover.
15. When installing the engine oil pressure switch, put sealant on the threads of the switch. Use 3M™ AAD Part #8672 or an equivalent. Use an oil pressure switch socket wrench (special tool #MD998012) to tighten the engine oil pressure switch and the oil filter bracket to 87 in-lbs (10 Nm).
16. Install the horizontal baffle plate.
17. Install the oil screen gasket.
18. Install the oil screen.
19. Install the vertical baffle plate.
20. To install the upper oil pan, do the following:
    • Step 1: Clean both gasket surfaces of the upper oil pan and cylinder block.
    • Step 2: Apply a 0.2 in (4 mm) diameter bead of sealant to the upper oil pan. Use Mitsubishi genuine parts #MD970389 or an equivalent. Apply the sealant by tracing the grooves and surrounding the bolt holes with a bead of sealant.

      CAUTION
      Make sure that when you install the upper oil pan you do not expel the sealant from the oil pan flange at area "Z" as shown.

    • Step 3: Install the oil pan to the bottom of the cylinder block.

      NOTE: Make sure you install the oil pan within 15 minutes while the sealant is still wet.

    • Step 4: Tighten the upper oil pan bolts in the sequence shown. Tighten the bolts to 80 in-lbs (9.0 Nm).

    Upper oil pan bolt tightening sequence (3.8L)

    NOTE: Wait for one hour after installing to allow the sealant to dry. During this time, keep oil and coolant away from the area.

21. Install the cover.
22. To install the lower oil pan, do the following:
    • Step 1: Clean both of the gasket surfaces on the upper and lower oil pans.
    • Step 2: Apply a 0.2 in (4 mm) diameter bead of sealant to the lower oil pan. Use Mitsubishi genuine parts #MD970389 or an equivalent. A bead of sealant must be applied on the grooves and around the bolt holes.
    • Step 3: Install the lower oil pan onto the upper oil pan.

      NOTE: Make sure you install the oil pan within 15 minutes while the sealant is still wet.

    • Step 4: Tighten the lower oil pan bolts in the sequence shown. Tighten the bolts to 98 in-lbs (11 Nm).

    Lower oil pan bolt tightening sequence (3.8L)

    NOTE: Wait for one hour after installing to allow the sealant to dry. During this time, keep oil and coolant away from the area.

    CAUTION
    Make sure you install the drain plug gasket in the right direction because if installed in the wrong direction, the result will be oil leaks.

23. Install the drain plug gasket.
24. Install the drain plug.