ford Workshop Repair Guides

Ford Workshop Service and Repair Manuals

ABOUT US
Special Testing Procedures > < Transmission-Transaxle Connector Layouts

Focus 1999 (08.1998-12.2004)

Automatic Transmission/Transaxle - Vehicles With: 4F27E - Leakage Inspection Focus 1999 (08/1998-12/2004)
Diagnosis and Testing

General Equipment
UV fluid leak detection euipment
CAUTION:
CAUTION:Do not try to stop the fluid leak by increasing the torque beyond specifications. This may cause damage to the transaxle case threads.

Check the fluid filler tube at the transaxle case. If any leakage is found, install a new plug.

Check the fluid tubes and fittings between the transaxle and the cooler for looseness, wear or damage. If leakage cannot be stopped by tightening a fluid tube nut, install new components.

If the leak continues, install a new cooler line fitting and tighten to specification. The same procedure should be followed for fluid leaks between the cooler and the cooler line fittings in this section. REFER to Section  307-02 Transmission/Transaxle Cooling.

The cooler can be further checked for leaks. REFER to Section  307-02 Transmission/Transaxle Cooling.

If leakage is found at the transaxle range selector lever, install a new seal.

If leakage is found at the transaxle wiring harness connector, install a new O-ring.

The transaxle is equipped with the following components to prevent external fluid leakage:

  • sealer
  • lip-type seals
  • O-ring seals
  • seal rings
  • seal grommets
  • thread sealant
  • panfluid

External Sealing

 
Item
Part Number
Description
1
—
O-ring - Output speed sensor
2
—
Converter housing (sealant to case)
3
—
Seal - Fluid pump
4
—
Seal - Pump fluid
5
—
Case (sealant to converter housing)
6
—
O-ring - Turbine speed sensor
7
—
Seal assy - Differential
8
—
O-ring - Bulkhead wiring harness connector
9
—
Cover assy - End (sealant to case)
10
—
Seal - Case cover (end cover to case) (2)
11
—
Seal - Manual shaft - Fluid (2)
12
—
Pan - Fluid (sealant to case)

Fluid Leakage in Torque Converter Area

In diagnosing and correcting fluid leaks in the pump support and gear and torque converter area, use the following procedures to locate the exact cause of the leakage. Leakage between the transaxle and engine, as evidenced by fluid around the torque converter housing, may have several sources. By careful observation it is possible, in many instances, to pinpoint the source of leak before removing the transaxle from the vehicle. The paths which the fluid may take to reach the bottom of the torque converter housing are shown in the illustration. The five steps following correspond to the numbers in the illustration.

  1. Fluid leaking past the pump seal lip will tend to move along the impeller hub and onto the rear of the impeller housing. Except in the case of a total seal failure, fluid leakage past the lip of the seal will be deposited on the inside of the torque converter housing only, near the outside diameter of the housing. Fluid from the vent assembly may move along the impeller hub and onto the rear of the impeller housing. Fluid from a converter hub weld leak will move along a path on the inside of the converter housing.
  1. Fluid leakage past the outside diameter of the pump seal and pump body will follow the same path that leaks past the inside diameter of the pump seal follow. Fluid from a converter hub weld leak will move along a path on the inside of the converter housing.
  1. Fluid that leaks past a pump-to-case screw or pump gasket will be deposited on the inside of the torque converter housing only. Fluid will not be deposited on the rear of the torque converter.
  1. Fluid leakage from the converter drain plug, (model-dependent) converter seal weld or converter-to-flexplate stud weld will appear at the outside diameter of the torque converter on the rear face of the flexplate, and in the converter housing only near the flexplate. Fluid leaks from the torque converter will leave a ring of fluid around the inside of the torque converter housing.
  1. NOTE:
    NOTE:White facial tissue paper may aid in determining the color (red is transaxle fluid) and source of the leaking fluid.
    Engine oil leaks are sometimes incorrectly diagnosed as transaxle pump gasket leaks. The following areas of possible leakage should also be checked to determine if engine oil leakage is causing the concern.
  • Leakage at the valve cover gasket may allow oil to flow over the torque converter housing or seep down between the torque converter housing and cylinder block causing oil to be present in or at the bottom of the torque converter housing.
  • Oil gallery plug leaks will allow oil to flow down the rear face of the cylinder block to the bottom of the torque converter housing.
  • Leakage at the crankshaft rear oil seal will work back to the flexplate, and then into the torque converter housing.

Leak Check Test

  1. Original factory fill fluid is dyed red to aid in determining if leakage is from the engine or transaxle. The red color should assist in pinpointing the leak.
  1. Clean off any fluid from the top and bottom of the torque converter housing, of the case, and the rear face of the engine and oil pan. Clean the torque converter area by washing with a suitable nonflammable solvent and blow dry using compressed air.
  1. Wash out the torque converter housing, and the front of the flexplate. The torque converter housing may be washed out using cleaning solvent and a squirt-type oil can. Blow dry all washed areas using compressed air.
  1. Start and run the engine until the transaxle reaches its normal operating temperature. Observe the rear of the cylinder block and the top of the torque converter housing for evidence of fluid leakage. Raise and support the vehicle REFER to Section  100-02 Jacking and Lifting. Run the engine at fast idle, then at engine idle, occasionally shifting to the D and R positions to increase pressure within the transaxle. Observe the front of the flexplate, rear of the cylinder block (in as far as possible), and inside the torque converter housing and front of the transaxle case. Run the engine until fluid leakage is evident and the probable source of leakage can be determined.

Leak Check Test With Black Light

Fluid soluble aniline or fluorescent dyes premixed at the rate of 2.5ml (1/2 teaspoon) of dye powder to 0.24L (1/2 pint) of automatic transaxle fluid have proven helpful in locating the source of fluid leakage. Such dyes may be used to determine whether an engine fluid or transaxle fluid leak is present. An ultraviolet light must be used to detect the fluorescent dye solution.

Special Testing Procedures > < Transmission-Transaxle Connector Layouts