Tech Tip: Diagnosing Oil Leak on Ford's 7.3L Super Duty Truck Diesel Engine

Tech Tip: Diagnosing Oil Leak on Ford’s 7.3L Super Duty Truck Diesel Engine

Has anyone else experienced an oil leak around the oil pump outlet fittings on the Ford's 7.3 Super Duty truck diesel engines? Some 1998-2003 E-Series, 1999-2003 Super Duty, 2000-’03 Excursion and 2000-'03 F-650/750 vehicles equipped with a 7.3L diesel engine may exhibit an oil leak at the high-pressure ....

Has anyone else experienced an oil leak around the oil pump outlet fittings on the Ford’s 7.3 Super Duty truck diesel engines?

Answer: Some 1998-2003 E-Series, 1999-2003 Super Duty, 2000-’03 Excursion and 2000-’03 F-650/750 vehicles equipped with a 7.3L diesel engine may exhibit an oil leak at the high-pressure oil pump outlet fittings and/or end plug.

According to Ford, this type of leak may appear to be a rear main crankshaft seal, oil pan gasket or other engine oil leak due to the drain hole machined in the crankcase valley which allows any oil in the valley to run down the back of the engine (see Figure 1).

High-pressure oil pump leaks at the outlet fittings and/or end plug can be serviced without removing the pump assembly. Replace the

O-rings on the fillings and the end plug using kit 2C3Z-9G804-AA. All three O-rings should be replaced. Apply liquid thread sealer (included in the kit) prior to reinstallation.

Note: Do not remove the bottom plug — it is sealed in a different manner.

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