A Guide to the Engine Water Pump for the 1979-1987 Mercury Capri

The Most Common Ordering Mistake: Water Pump Rotation

Before buying a new water pump for your 1979-1987 Capri, you must know which rotation your car needs. This is the most critical detail. Using the wrong pump will cause your engine to overheat. The Capri used two different accessory belt systems during this period, which determines the type of pump required.

• Standard Rotation (Clockwise): Generally found on 1979-1985 models equipped with multiple V-belts. The water pump pulley on these systems is grooved and is driven by the inside of a V-belt.
• Reverse Rotation (Counter-Clockwise): Generally found on 1986-1987 models equipped with a single serpentine belt. The water pump pulley on these systems is smooth and is driven by the flat, back side of the belt, causing it to spin in the opposite direction.

Signs of a Failing Water Pump

A water pump is a wear item and will eventually fail. Luckily, it usually provides clear warning signs. Ignoring these can lead to expensive engine damage.

• Coolant Leaks: This is the most common symptom. You may find puddles of green or orange fluid under the front of your engine. Look for stains or drips coming from a small hole on the bottom of the pump, known as the 'weep hole'. This hole is designed to leak when the internal seals fail.
• Engine Overheating: If the pump's internal impeller is damaged or it can no longer circulate coolant effectively, your temperature gauge will climb into the red. If this happens, pull over and shut off the engine immediately to prevent warping a cylinder head or blowing a head gasket.
• Whining or Grinding Noises: A high-pitched whine or a rough, grinding sound from the front of the engine that changes with RPM can signal that the bearings inside the water pump are failing.
• Wobbly Pulley: With the engine off, try to wiggle the water pump pulley. If you feel any side-to-side or in-and-out play, the shaft bearing is worn out and the pump needs to be replaced soon.

Choosing the Right Aftermarket Water Pump

Since new original Ford (Motorcraft) parts for a car of this age can be difficult to find, the aftermarket is your best source. Aftermarket pumps fall into two main categories:

Tier 1: Standard OE-Style Replacements

These pumps are designed to meet or exceed the performance of the original factory part. They are perfect for daily drivers, restorations, and stock or lightly modified engines. They offer reliability and a direct fit without modifications.

• Gates: A well-known and reputable brand, often associated with belts and hoses, their water pumps are considered a quality replacement part by many mechanics and DIYers.
• GMB: Another widely used brand that has a long history of producing reliable water pumps. Forum users report good experiences and longevity with GMB pumps.
• US Motor Works / WJB: These brands offer budget-friendly options that serve as functional replacements for a standard vehicle.

Tier 2: High-Volume & Performance Pumps

If your Capri is modified for higher horsepower or you simply want an upgrade for better cooling efficiency, a high-volume pump is a good choice. These pumps use improved impeller designs to flow more coolant at all engine speeds, which can help lower engine temperatures.

• Edelbrock: A top name in performance parts, Edelbrock's Victor series water pumps are known for their improved impeller design and durable construction, which can lower operating temperatures. Be aware that some owners have reported needing to do minor grinding for clearance on aftermarket timing covers or balancers.
• Proform / PRW: These brands also offer high-performance aluminum water pumps that provide increased flow and are lighter than stock cast iron units.

Cost of a New Aftermarket Water Pump (1979-1987 Mercury Capri)

Frequently Asked Questions (FAQ)