Section 03-01B: Engine, 5.0L HO and 5.0L Cobra
1994 Mustang Workshop Manual
DISASSEMBLY AND ASSEMBLY

Engine

 

Disassembly

NOTE: Before starting disassembly, remove all wiring harnesses, emission control system, fuel system, ignition system, flywheel (6375) , engine rear plate (7007) and front end accessory drive components.

With engine mounted on a work stand:

  1. Remove the upper and lower intake manifolds (9424) as outlined.
  1. Remove the left and right hand valve covers (6582) and discard the valve cover gaskets (6584) .

    Mustang





    Item Part Number Description
    1 9E434 Cover Plate
    2 390652 Screw (4 Req'd)
    3A 391176 Bolt (2 Req'd)
    4A 56335 Bolt (2 Req'd)
    5 9424 Upper Intake Manifold
    6 9H486 Intake Manifold Upper Gasket
    7 9424 Lower Intake Manifold
    8B 390591 Stud (4 Req'd)
    9A 390358 Bolt (2 Req'd)
    A Tighten to 16-24 Nm (12-18 Lb-Ft)
    B Tighten to 2.7-5.4 Nm (2-4 Lb-Ft)


Cobra





Item Part Number Description
1A 391448 Bolt (2 Req'd)
2A 390358 Bolt
3A 390653 Bolt (2 Req'd)
4 9424 Upper Intake Manifold
5 9H486 Intake Manifold Upper Gasket
6 9424 Lower Intake Manifold
7B — Stud (4 Req'd)
8A — Stud Bolt
A Tighten to 16-24 Nm (12-18 Lb-Ft)
B Tighten to 2.7-5.4 Nm (2-4 Lb-Ft)

NOTE: All valve train components should be identified to ensure they are installed in their original positions during assembly.

  1. Remove the oil level indicator (6750) and oil level indicator tube (6754) and remove the oil bypass filter (6714).
  1. Remove the rocker arms (6564), rocker arm seat (6A528) , push rods (6565) , valve tappet guide plates (6K512) and valve tappets (6500) and remove the cylinder heads (6049) as outlined.

    Mustang





    Item Part Number Description
    1A 390385 Bolt
    2 6A528 Rocker Arm Seat
    3 6564 Rocker Arm
    4 6A588 Rocker Arm Fulcrum Guide
    5 6049 Cylinder Head
    A Tighten to 24-34 Nm (18-25 Lb-Ft)


    Cobra





    Item Part Number Description
    1 6564 Roller Rocker Arm
    2A 391423 Bolt
    3 6A588 Rocker Arm Fulcrum Guide
    4 6049 Cylinder Head
    A Tighten to 24-34 Nm (18-25 Lb-Ft)
  1. Remove the crankshaft pulley (6312) and damper as outlined.
  1. Remove the water pump (8501) and engine front cover (6019) as an assembly. Discard the engine timing cover gasket (6020) and crankshaft front seal (6700) .
  1. Remove the oil pan (6675) and discard the oil pan gasket (6710) .
  1. Remove the oil pump (6600) , oil pump screen cover and tube (6622) and oil pump intermediate shaft (6A618) .




    Item Part Number Description
    1A 33771-S2 Nut
    2B 357235-S Bolt (2 Req'd)
    3 6626 Oil Pump Inlet Tube Gasket
    4 6600 Oil Pump
    5 6A618 Oil Pump Intermediate Shaft
    6A 57647-S Bolt (2 Req'd)
    7 6622 Oil Pump Screen Cover and Tube
    A Tighten to 30-43 Nm (22-32 Lb-Ft)
    B Tighten to 16-24 Nm (12-18 Lb-Ft)
  1. Remove the crankshaft rear oil seal (6701) .
  1. Remove the camshaft sprocket, retainer bolt and washer. Slide the sprockets and timing chain forward and remove the chain and sprockets as an assembly.



  1. Remove the camshaft thrust plate (6269) and remove the camshaft (6250) .

    NOTE: Pistons (6108), connecting rods (6200) and connecting rod bearings (6211) should be numbered to ensure they are assembled in their original positions.

    NOTE: Before removing pistons , inspect the top of the cylinder bores. If necessary, remove the ridge and/or carbon deposits from each cylinder using Rotunda Cylinder Ridge Reamer 014-00292 or equivalent.

  1. Remove the connecting rod caps and remove the pistons .

     CAUTION: When removing the crankshaft (6303) , take care not to damage any of the bearing surfaces on the crankshaft or damage to engine may occur.

    NOTE: The location of the main bearing caps and the crankshaft main bearings (6333) should be identified. When the engine is assembled, crankshaft main bearings which are to be reused should be installed in their original positions.

  1. Remove the crankshaft main bearing caps, crankshaft main bearings and crankshaft .
  1. For cleaning purposes, the oil gallery and coolant drain plugs can be removed.
 

Assembly

Before assembling cylinder block (6010) , all sealing surfaces must be clean and free of chips, dirt, paint and foreign material. Also ensure coolant and oil passages are clear.

If new piston rings are to be installed and no visible cross-hatch marks remain on the cylinder wall, remove cylinder wall glaze using a spring-type tool. Follow instructions of tool manufacturer.

NOTE: Lightly oil all retaining bolt and stud threads before installation, except those specifying special sealant.

  1. Place upper crankshaft main bearings in position in the bores with the tang fitting in the slot provided. Lubricate crankshaft main bearings with Engine Assembly Lubricant D9AZ-19579-D or equivalent meeting Ford specification ESR-M99C80-A.
  1. Install the lower crankshaft main bearings in the crankshaft main bearing caps.
  1. Carefully lower crankshaft into place. Use care to prevent damage to bearing surfaces.
  1. Check clearance of each crankshaft main bearing following the procedure under Fitting Main and Connecting Rod Bearings in Section 03-00.
  1. After bearings have been fitted, apply a light coat of Engine Assembly Lubricant D9AZ-19579-D or equivalent meeting Ford specification ESR-M99C80-A to the journals and bearings.

     CAUTION: Ensure main bearing caps are installed in their original position or damage to engine may occur.

  1. Install all crankshaft main bearings and caps except thrust bearing cap (No. 3 crankshaft thrust main bearing (6337) ). Tighten main bearing caps to 81-95 Nm (60-70 lb-ft).

    NOTE: Apply sealer Silicone Rubber D6AZ-19562-AA or BA or equivalent meeting Ford specification ESB-M4G92-A and ESE-M4G195-A in a 1.59mm (1/16 inch) bead in each corner of rear main bearing cap saddle and full length of the saddle.

  1. Install thrust main bearing cap (No. 3) with bolts finger-tight.




    Item Part Number Description
    1 388813 Bolt 5/8-18
    2 6378 Damper Washer
    3 6312 Crankshaft Pulley
    4 6316 Crankshaft Damper
    5 6306 Crankshaft Sprocket
    6 388907 Crankshaft Key
    7 6303 Crankshaft
    8 6333 Upper Crankshaft Main Bearing
    9 6337 Upper Crankshaft Thrust Main Bearing
    10 6375 Flywheel
    11 6701 Crankshaft Rear Oil Seal
    12 6333 Lower Crankshaft Main Bearing
    13 6337 Lower Crankshaft Thrust Main Bearing
    14 — Main Bearing Rear Cap (Part of 6010)
    15 — Main Bearing Rear Intermediate Cap (Part of 6010)
    16 — Main Bearing Center Cap (Part of 6010)
    17 — Main Bearing Front Intermediate Cap (Part of 6010)
    18 — Main Bearing Front Cap (Part of 6010)
    19 391546 Main Bearing Cap Stud
    20 391547 Main Bearing Cap Bolt (9 Req'd)
    21 N804586-S2 Bolt (4 Req'd)
  1. Pry crankshaft forward against thrust surface of upper crankshaft thrust main bearing .
  1. Hold crankshaft forward and pry main thrust bearing cap to the rear. This will align thrust surfaces of both halves of crankshaft thrust main bearing.
  1. Retain forward pressure on crankshaft . Tighten cap bolts to 81-95 Nm (60-70 lb-ft).
  1. Force crankshaft toward the rear of engine.



  1. Check crankshaft end play. Refer to Section 03-00.
  1. Install crankshaft rear oil seal as outlined. Install engine rear plate and flywheel . Tighten bolts to 102-115 Nm (75-85 lb-ft).
  1. Coat all camshaft bearings (6261) , camshaft lobes and gear with Engine Assembly Lubricant D9AZ-19579-D or equivalent meeting Ford specification ESR-M99C80-A.
  1. Carefully slide camshaft through camshaft bearings . Install camshaft thrust plate with groove toward cylinder block . Tighten thrust plate retaining bolts to 12-16 Nm (9-12 lb-ft).




    Item Part Number Description
    1 6256 Camshaft Sprocket
    2 6268 Timing Chain
    3 6261 Camshaft Bearing (5 Req'd)
    4 6266 Camshaft Rear Bearing Cover
    5 6250 Camshaft
    6 391269 Dowel Pin
    7 6269 Camshaft Thrust Plate
    8 390392 Thrust Plate Bolt (2 Req'd)
    9 43002 Bolt
    10 6278 Camshaft Sprocket Washer
  1. Check camshaft end play. Refer to Section 03-00. If not within specification, replace camshaft thrust plate .
  1. Install camshaft sprocket, timing chain and crankshaft sprocket. Position camshaft sprocket and timing chain on camshaft and crankshaft sprocket simultaneously. Ensure timing marks on the sprockets are aligned.
  1. Install washer and camshaft sprocket retainer bolt. Tighten camshaft sprocket retainer bolt to 54-61 Nm (40-55 lb-ft).



  1. Oil the piston rings, pistons and cylinder walls with clean engine oil XO-10W30-QSP or DSP or equivalent meeting Ford specification ESE-M2C153-E. Be sure to install the pistons in the same cylinders from which they were removed.
  1. Ensure the ring gaps are properly spaced around the circumference of the piston . Refer to Piston and Connecting Rod Installation as outlined.

     CAUTION: Install piston with indentation notch in the piston head toward front of engine or damage to engine may occur.

  1. Install Rotunda Piston Ring Compressor 014-000290 or equivalent on the piston and push piston in with a hammer handle until it is slightly below top of cylinder. Be sure to guide connecting rods to avoid damaging crankshaft journals (cover studs).



  1. Check clearance of each connecting rod bearing . Refer to procedure in Section 03-00.
  1. After connecting rod bearings have been fitted, apply a light coat of Engine Assembly Lubricant D9AZ-19579-D or equivalent meeting Ford specification ESR-M99C80-A to the journals and connecting rod bearings .
  1. Turn the crankshaft throw to the bottom of its stroke. Push piston all the way down until connecting rod bearing seats on the crankshaft journal.
  1. Install connecting rod cap. Tighten nuts to 26-32 Nm (19-24 lb-ft).
  1. After piston and connecting rods have been installed, check side clearance between connecting rods on each crankshaft journal.



  1. Prime the oil pump and install oil pump intermediate shaft and oil pump screen cover and tube . Tighten oil pump retaining bolts to 30-43 Nm (22-32 lb-ft).




    Item Part Number Description
    1A 33771-S2 Nut
    2B 357235-S Bolt (2 Req'd)
    3 6626 Oil Pump Inlet Tube Gasket
    4 6600 Oil Pump
    5 6A618 Oil Pump Intermediate Shaft
    6A 57647-S Bolt (2 Req'd)
    7 6622 Oil Pump Screen Cover and Tube
    A Tighten to 30-43 Nm (22-32 Lb-Ft)
    B Tighten to 16-24 Nm (12-18 Lb-Ft)
  1. Install crankshaft front seal in engine front cover as outlined.
  1. Install crankshaft front seal , engine timing cover gasket and engine front cover . Tighten engine front cover bolts to 16-24 Nm (12-18 lb-ft). (Refer to procedure in this section.) Also install crankshaft damper and crankshaft pulley and tighten bolt to 149-176 Nm (110-130 lb-ft).
  1. Install new oil bypass filter .
  1. Install oil pan gasket and oil pan . Tighten the oil pan bolts to 12-16 Nm (110-144 lb-in).
  1. Install valve tappets in their original bores.
  1. Install valve tappet guide plates and valve tappet guide plate retainers (6C515) . Tighten bolts and washers to 8-12 Nm (71-106 lb-in).

    NOTE: If cylinder heads were completely disassembled, refer toCylinder Head Disassembly and Assembly as outlined.

  1. Position head gaskets (6051) on cylinder block . Install cylinder head to block dowels (6A008) . Install cylinder heads .

     CAUTION: Cylinder head retaining bolts must be replaced with new bolts, DO NOT REUSE original cylinder head retaining bolts. They are torque-to-yield bolts and cannot be reused or possible engine damage may occur.

  1. The cylinder head bolts are tightened in three steps:

    Refer to the following illustration for the tightening sequence.

    1. Tighten all bolts in sequence to 34-47 Nm (25-35 lb-ft).
    1. Tighten all bolts in sequence to 61-75 Nm (45-55 lb-ft).
    1. Tighten all bolts in sequence an additional 1/4 turn (85-95 degrees).

      NOTE: The RH cylinder head has one stud at location 8. The LH cylinder head does not.





  1. Install push rods , rocker arm fulcrum guides (6A588) , rocker arm seats and rocker arms or roller rocker arms and tighten rocker arm bolts to 24-34 Nm (18-25 lb-ft).

    NOTE: Sealer sets up in 15 minutes so it is important that assembly be completed promptly.

  1. Apply sealer at points shown and install intake manifold gaskets (9439) and end seals.



  1. Install lower and upper intake manifold . Use guide pins to ease installation of intake manifold onto cylinder head .
  1. Tighten intake manifold bolts as outlined.


Mustang Shown, Cobra Similar




  1. Install oil level indicator tube and oil level indicator .
  1. Position valve cover gaskets in each valve cover and install valve covers . Install valve cover bolts and tighten to 16-20 Nm (12-15 lb-ft).



  1. Install wiring harnesses, water pump , emission control system, fuel system, and ignition system and front end accessory drive components. Refer to appropriate engine section.