The 5 Most Common Ford 460 Engine Problems

Ford’s big block V8 460 engine has been around since 1968 and is still in use today. In its thirty-year lifespan, the 460’s 7.5L big block V8 engine produced power outputs ranging from 197 horsepower to 245 horsepower. Ford’s 460 engine has seen numerous updates, improvements, and total redesigns over the years.

There are several big-block V8 engine families, and the 460 comes from one of them: the 385 Lima engine family. The 385 engine family included the 7.5L 460, as well as the 370/6.1L, 429/7.0L, and 514/8.4L.

Ford redesigned the heads and camshafts in the early 1970s, lowering the compression ratio and refreshing the camshafts. Due to their notorious unreliability, the newly designed heads underwent another complete redesign in 1973. The addition of fuel injection was the most significant engine upgrade in 1988.

The 460 engine was available as a performance crate engine until 1997 in addition to being used in Ford, Lincoln, and Mercury vehicles. Crate engines of the Ford 460 have become popular in hot rods, where they can produce over 500hp when properly fueled.

In spite of its already considerable size, the 460’s displacement can be increased by 545 cubic inches, from 7.5L to 8.9L.

Ford 460 Engine Applications

  • 1968-1971 Lincoln Continental Mark III
  • 1972-1976 Ford Thunderbird
  • 1974-1976 Mercury Cougar
  • 1972-1978 Ford & Mercury Full-Size Vehicles
  • 1973-1976 Ford & Mercury Mid-Size Vehicles
  • 1973-1998 Ford F-Series
  • 1975-1996 Ford E-Series

The 460 engine was commonly used in a wide range of commercial vehicles, RVs, buses, and other forms of transportation in addition to those listed above.

Ford 460 Engine Problems

  • Timing Cover Leaks
  • Water Pump Failure
  • Rear Main Seal Leaks
  • Warped Exhaust Manifolds
  • Oil Cooler Failure

1. Ford 460 Leaking Timing Chain Cover

Protects the timing chain, tensioners, and guides by mounting to the front of the engine block with bolts. The timing chain is lubricated with oil as well as protecting it from road grime and debris. In order to avoid stretching, the timing chain needs to be properly lubricated because of the metal gears it sits on.

A gasket separates the timing cover from the engine block before it is bolted on. Coolant leaks can occur in a few different places on a Ford 460.

Ford 460 Leaking Timing Chain Cover

Heat and normal wear and tear on the timing cover can cause cracks or holes in the cover, which can lead to leaks. Coolant leaks can also be caused by the timing cover-to-block gasket wearing down over time. Between the water pump and the timing cover, there is also a backing plate with holes that can leak.

If your coolant is leaking, your engine is more prone to overheating, which can warp important parts like the head or timing chain or damage the engine’s rods and pistons internally. Lack of lubrication from an oil leak can cause the timing chain to jump teeth, which can cause timing to be thrown off.

Leaking Timing Cover Symptoms

  • Oil or coolant leaks on block
  • Low oil or coolant levels
  • Engine overheating
  • Rough idling or poor performance

2. 7.5L 460 Water Pump Failure or Leaking

Water pumps are in charge of moving coolant around the engine’s block as needed. The water pump and its internals degrade over time because it is a pressurized system. Both carbureted and fuel-injected versions of the Ford 460 are notorious for sapping power from the water pumps.

The factory water pump bearings on the 460 were a common point of failure because they were weak. Additionally, if the fan belt is overtightened, the pump will malfunction as a result of the added stress.

Ford 460 Water Pump Failure or Leaking

The water pump vent hole, which is also known as the weep hole, is another place where coolant leaks. There’s a vent hole in case the seal fails. The vent hole will be dripping with either oil or coolant.

If oil is dripping from the hole, your pump’s oil seal is faulty and needs to be replaced. When the oil seal fails, oil drips from the weep hole into the coolant, where it cannot be contaminated.

In the event that coolant is leaking, the internal water pump seal is likely to be damaged or destroyed. A new water pump is required in both scenarios.

Water Pump Failure Symptoms

  • Engine overheating
  • Fan constantly on
  • Coolant leaks from water pump
  • Whining noise

3. Ford 460 Rear Main Seal Leaks

It seals the main crankshaft bearing and is located on the back of the engine block. Because the crankshaft carries the most weight in an engine, the bearings that support it must be large.

Known as “main bearings,” these bearings help support the crankshaft during operation. The rear main seal protects the main bearing at the back. The seal on the rear main bearing prevents oil from leaking from the crankshaft, which is located on the outside of the block.

The rear main seal is particularly vulnerable to damage because of its position in the engine. The seal degrades over time due to the crankshaft’s rotation. Oil leaks are frequently caused by Ford 460 rear main seal failure.

Ford 460 Rear Main Seal Leaks

Low oil levels or infrequent oil changes can cause the seal to wear out more frequently and quickly than on properly maintained engines, even though it naturally degrades over time.

Another reason for seal failure could be due to worn bearings, worn crankshaft, or an ineffective PCV system. If you leave your car for an extended period of time without driving it, the seal will dry out, become brittle, and begin to leak.

Rear Main Seal Leak Symptoms

  • Oil puddles under car near back of block
  • Low engine oil

As a result of the seal’s location and the only symptoms being oil stains on your driveway, it can be difficult to identify a rear main seal leakage. It’s a bummer that changing the rear main seal is such a hassle because it necessitates removing the transmission and oil pan.

Rear main seal leaks can be repaired in a variety of ways, one of which is by using BlueDevil Rear Main Sealer. Directly added to the engine oil, these sealants are designed to stop leaks. Replacing the rear main seal is a pain, so it’s worth it to try to stop the leak before replacing it.

4. Ford 460 Warped Exhaust Manifolds & Broken Bolts

The first part of the exhaust system is the exhaust manifold, a large cast-iron piece that attaches directly to the engine block. It’s responsible for transporting exhaust gases from valves all the way to the exhaust hoses. Because it’s bolted to the engine block and gets blasted by hot exhaust gas, this component can get extremely hot.

Ford 460 Warped Exhaust Manifolds & Broken Bolts

Metallic materials go through repeated heating and cooling cycles. The metal in your car heats up when the engine is running and cools down when it is stopped. Metal stretches when heated and shrinks when cooled. Thus, the 460 engine’s exhaust manifold expands and contracts continuously.

Metal can warp or crack as a result of this expansion and contraction, resulting in exhaust leaks. These same heat cycles also frequently break off the bolts holding the manifold in place on the block.

In the event of a broken bolt, the exhaust air manifold may become detached from the engine block and begin leaking. Vacuum leaks caused by exhaust leaks reduce backpressure and degrade performance.

Ford 7.5L Bad Exhaust Manifold Symptoms

  • Louder exhaust noise when in cab
  • Exhaust fumes in cab
  • Lack of acceleration
  • Loss of power and overall poor performance

A broken bolt can be easily replaced, but getting the broken bolt out of the block may be difficult If the manifold is cracked, warped, or otherwise defective, you’ll have to replace it. Instead of swapping out the manifold for an OEM model, many people opt to install a new set of headers.

Exhaust manifolds and headers are nearly identical, with the exception that each valve or cylinder has its own exhaust piping. Headers keep the air separate while manifolds combine it all into one pipe. As a result of the separation, exhaust gas temperatures and therefore overall engine temperatures are kept at a lower level.

5. Ford 7.5L 460 Oil Cooler Failure

The 460-hp Ford engines came equipped with an oil cooler as standard equipment. An oil cooler’s job is to keep engine oil from becoming too hot by removing heat from the system. Since engine oil circulates throughout the cooling system, the oil itself can assist in cooling the block, internals, and various other components of the engine. Engine.

When it comes to cooling, the 460 has an oil cooler style heat exchanger. Engine coolant flows through the tubes of the oil cooler, which collects oil and cools it. The coolant aids in lowering the oil’s temperature as it passes through the tubes.

Ford 7.5L 460 Oil Cooler Failure

Due to the fact that the oil and coolant flow through the same system, if it fails, coolant and oil will mix, resulting in severe engine damage. The oil coolers in the 460 have a history of internal failure, resulting in a mixture of the two fluids.

After the coolant has been drained, it is recirculated throughout the engine. Due to its lower lubricity, coolant can deprive internal components of the lubrication they require, which can lead to serious problems.

A common solution for 7.5L owners is to get rid of or replace the OEM oil cooler with an aftermarket one, even though poor cooling system maintenance is usually to blame.

Oil Cooler Failure Symptoms

  • Coolant or oil leaking from oil cooler
  • Oil in the cooling system
  • Coolant in the oil system

Symptoms such as engine knock or extremely poor performance indicate internal damage if you are experiencing anything other than these. When the oil cooler fails, the engine must be shut down immediately and the cooling and oil systems must be flushed.

7.5L Ford 460 Reliability

The 30-year history of the 460 engine is a testament to its dependability. While the oil cooler, water pump, gaskets, and seals have been mentioned as common problems above, the majority of these issues are caused by natural wear and tear.

Maintenance can help extend the life of these components, but the majority will fail on any old, high-mileage engine if not properly cared for.

To put it another way, the engine’s core components—the block and head—are incredibly strong. The vast majority of the engine’s issues are caused by supporting systems rather than the engine’s core.

Final words

Engine reliability is a strong suit for the 7.5L 460 from Ford. Old age and high mileage are the most common causes of problems with engines over 25 years old. The engine block and major components are capable of withstanding well over 300,000 miles on their own.

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