Section 03-01B: Engine, 5.0L HO and 5.0L Cobra
1994 Mustang Workshop Manual
IN-VEHICLE SERVICE

Hydraulic Valve Tappet

Before replacing a hydraulic valve tappet (6500) for noisy operation, ensure the noise is not caused by improper valve to rocker arm clearance or by worn rocker arms (6564) or push rods (6565) .

 

Removal

  1. Remove the intake manifold (9424) and related parts as outlined.
  1. Remove the valve covers (6582) . Loosen the rocker arm seat bolts and rotate the rocker arms to the side.
  1. Remove the push rods and identify them so that they can be installed in their original positions.
  1. Remove the valve tappet guide plate retainer bolts.
  1. Remove the valve tappet guide plate retainers (6C515) and valve tappet guide plates (6K512) . Identify the valve tappet guide plates so they may be installed in their original positions.
  1. Using a magnet, remove the valve tappets and place them in order so that they can be installed in their original bores.

    If the valve tappets cannot be removed from their bores due to excessive varnish, etc., it may be necessary to use a claw-type tool or a magnet to remove them. Rotate the valve tappet back and forth to loosen the valve tappet from the gum or varnish that may have formed on the valve tappet .

    If necessary to disassemble a valve tappet , refer to Valve Tappet Disassembly and Assembly as outlined.



 

Installation

Valve tappets and bores are to be lubricated with Engine Assembly Lubricant D9AZ-19579-D or equivalent meeting Ford specification ESR-M99C80-A before installation.

  1. Clean outside of valve tappets and install in the bores from which they were removed. If a new valve tappet is being installed, check the new valve tappet for a free fit in the bore in which it is to be installed. Lubricate the valve tappet and bore with Engine Assembly Lubricant D9AZ-19579-D or equivalent meeting Ford specification ESR-M99C80-A before inserting the valve tappet in the bore.
  1. Install valve tappet guide plates in their original positions then install valve tappet guide plate retainer .
  1. Install the push rods in their original position. Apply Multi-Purpose Grease D0AZ-19584-AA or equivalent meeting Ford specification ESR-M1C159-A and ESB-M1C93-A to the valve stem tips and the push rod ends.
  1. Lubricate the rocker arms and rocker arm seat (6A528) or roller rocker arms with Engine Assembly Lubricant D9AZ-19579-D or equivalent meeting Ford specification ESR-M99C80-A. Position the rocker arms over the push rods and tighten rocker arm seat bolts to 24-34 Nm (18-25 lb-ft). Perform a valve clearance adjustment as outlined.
  1. Install the valve covers with a new valve cover gasket (6584) or equivalent where specified.
  1. Install the intake manifolds and related parts.
  1. Run the engine and check for leaks.


Mustang





Item Part Number Description
1A 57621-S2 Valve Tappet Guide Plate Retainer Plate Bolt (2 Req'd)
2 6C515 Valve Tappet Guide Plate Retainer
3 6565 Push Rod (16 Req'd)
4 6K512 Valve Tappet Guide Plate (8 Req'd)
5 6500 Roller Valve Tappet (16 Req'd)
6 6A588 Rocker Arm Fulcrum Guide (8 Req'd)
7 6564 Rocker Arm (16 Req'd)
8 6A528 Rocker Arm Seat (16 Req'd)
9B 390385 Rocker Arm Seat Bolt (16 Req'd)
A Tighten to 8-12 Nm (71-106 Lb-In)
B Tighten to 24-34 Nm (18-25 Lb-Ft)


Cobra





Item Part Number Description
1A 57621-S2 Valve Tappet Guide Plate Retainer Bolt (2 Req'd)
2 6C515 Valve Tappet Guide Plate Retainer
3 6565 Push Rod (16 Req'd)
4 6K512 Valve Tappet Guide Plate (8 Req'd)
5 6500 Roller Valve Tappet (16 Req'd)
6 6A588 Rocker Arm Fulcrum Guide (8 Req'd)
7 6564 Roller Rocker Arm (16 Req'd)
8B 391423 Rocker Arm Seat Bolt (16 Req'd)
A Tighten to 8-12 Nm (71-106 Lb-In)
B Tighten to 23-34 Nm (18-25 Lb-Ft)