Diagnosing Oil Leak on Ford's 7.3L Super Duty Truck Diesel Engine - Engine Builder Magazine

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

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.
Figure 1

You May Also Like

Shop Solutions March 2024

I always keep a pair of needle nose pliers and a small, straight screwdriver in my blast cabinet to hold small parts when blasting.

Engine Builder and Engine Pro present Shop Solutions in each issue of Engine Builder Magazine and at enginebuildermag.com to provide machine shop owners and engine technicians the opportunity to share their knowledge to benefit the entire industry and their own shops. Those who submit Shop Solutions that are published are awarded a prepaid $100 Visa gift card. Submit your Shop Solution at [email protected]. You must include your name, shop name, shop address and shop telephone number. Submitted Shop Solutions not published will be kept on file and reevaluated for each month’s new entries.

Degreeing the Camshaft and Checking Valve-to-Piston Clearance

Jeff McCord of LinCo Diesel Performance walks you through degreeing a camshaft and checking valve-to-piston clearance.

Designing a Better LS Engine

After a customer wanted a Steve Morris Engines’ SMX in an LS version, Steve saw the upside and potential in the market, and a challenge to build a better LS.

The Importance of a Good Valve Job

The valve job ensures the mating surfaces of the valves and the seats properly control the air/fuel mixture.

Other Posts

Getting Better Cylinder Head Airflow

When it comes to improving horsepower and rpm, airflow has a lot to do with it, and it seems the job is one that’s never finished.

Horsepower and Head Gasket Technology

Head gaskets have one of the toughest job in an engine, and now we’re pushing them harder than ever, making it easier to expose the slightest weakness.

Inside the Development of Frankenstein’s F-Series LS Cylinder Heads

Right away, engine builders knew it was special.

Shop Solutions – January 2024

Before installing cam bearings, make sure to chamfer any oil holes and clean up back grooves of any sharp edges.