The 5 Typical Ford 460 Engine Issues. The Ford 460 engine is the company’s longest-running big block V8, having been built from 1968 until 1998. The 460 engine is a 7.5L big block V8 with a 30-year history of producing power ratings ranging from 197hp to 245hp. The big block 460 cubic inch engine survived 30 years in production due to its dependability. However, no engine is flawless, and this is no exception. In this essay, I discuss Ford 460 engine difficulties and reliability, as well as some history and extra information.
History of the Ford 7.5L Big Block
Ford’s 460 engine has been updated, improved, and completely redesigned over the years. The 460 is a member of the 385 Lima engine family, which consists of big-block V8s manufactured in Ford’s Lima, Ohio plant. The 385 engine family also comprised a 370/6.1L, 429/7.0L, and 514/8.4L in addition to the 7.5L 460.
Ford updated the camshaft, reduced the compression ratio, and entirely rebuilt the heads in the early 1970s. The new heads were extremely unstable, prompting a complete redesign in 1973. The adoption of fuel injection was the most significant engine development in 1988.
The 460 engine was available as a performance crate engine until 1997, in addition to its usage in Ford, Lincoln, and Mercury automobiles. The Ford 460’s availability as a crate engine led to its popularity as a hot rod engine, capable of producing over 500hp with correct fueling. The 460 can be stroked out to 545 cubic inches, boosting displacement from 7.5L to 8.9L despite its already huge size.
Engine Applications for the Ford 460
- Lincoln Continental Mark III, 1968-1971
- Ford Thunderbird, 1972-1976
- 1974-1976 The Mercury Cougar
- Ford and Mercury Full-Size Vehicles from 1972 to 1978
- Ford and Mercury Mid-Size Vehicles from 1973 to 1976
- Ford F-Series (from 1973 to 1998)
- Ford E-Series (from 1975 to 1996)
In addition to the cars indicated above, the 460 engine was widely employed in commercial vehicles, RVs, buses, and so on.
Ford 460 Engine Issues
The following are some of the most prevalent Ford 460 engine problems:
- Coverage Time Leaks
- Failure of a Water Pump
- Leaks in the Rear Main Seal
- Exhaust Manifolds That Are Warped
- Failure of the Oil Cooler
In the following sections, I go over the aforementioned Ford 460 issues in detail. These failures will not affect everyone, but they are among the most common problems with the Ford 7.5 big block engine. Furthermore, because this engine is now 25-50 years old, some extra care and maintenance is likely required. Anyway, let’s look at these engine issues before returning to reliability near the end of the paper.
1. Ford 460 Timing Chain Cover Leak
The timing cover bolts to the front of the engine block to protect the timing chain, guides, and tensioners. It not only protects these components from road debris, filth, and grime, but it also helps to keep the timing chain lubricated with oil. Because the timing chain is a metal component that rides on metal gears, it requires sufficient lubrication or it would expand due to friction and heat.
A gasket is installed between the timing cover and the block. There are a few common spots on the Ford 460 where coolant leaks occur.
Heat and typical wear and tear can cause the timing cover to crack or produce holes over time, resulting in leaks. Furthermore, the gasket between the timing cover and the block wears out with time and might cause coolant leakage. Finally, a backing plate that stands between the water pump and the timing cover is prone to leaking.
When coolant leaks, the engine overheats, which can deform critical components like the head or timing chain and cause internal damage to rods and pistons. Low oil levels can deprive the timing chain of lubrication, causing the timing chain to jump teeth and throw timing off.
Symptoms of Timing Cover Leakage
Symptoms of a leaky timing cover on a Ford 460 include:
- Block oil or coolant leaks
- Low quantities of oil or coolant
- Overheating of the engine
- Inefficient idle or poor performance
Problems with the Ford 460 Water Pump
Water pumps are in charge of moving coolant throughout the engine block. The water pump and its internals deteriorate with time because it is a pressurised device. The Ford 460, both carbureted and fuel injected, is notorious for consuming water pumps. The water pump bearings on the OEM pumps on the 460 were not particularly sturdy and were a regular failure location. Furthermore, overtensioning the fan belt would add additional stress and cause the pump to fail.
Coolant has also been reported to leak through the water pump vent hole, sometimes known as the weep hole. The vent hole serves as a warning if the seal fails. The vent hole will leak either oil or coolant. If oil is flowing from the hole, it indicates that the oil seal inside the pump is deteriorating. When the oil seal fails, oil drips through the weep hole and does not contaminate the coolant. If the coolant is leaking, the internal water pump seal is blown. In both of these cases, a new water pump is required.
Symptoms of Water Pump Failure
- Overheating of the engine
- The fan is always on.
- Leaks of coolant from the water pump
- Whining sound
3. Rear Main Seal Leaks on a Ford 7.5 Big Block
The rear main seal is located on the engine block’s backside and seals the main crankshaft bearing. Because the crankshaft bears the most load of any component in an engine, it is supported by the largest bearings. These are the “main bearings” and help to support the crankshaft’s load. The rear main seal is the rear main bearing seal. The rear main bearing is located on the exterior of the back of the block, and the seal is responsible for preventing oil leakage from the crankshaft.
Because of its location in the engine, the rear main seal is subject to a great deal of stress. The seal wears down naturally as the crankshaft turns. Failure of the rear main seal on the Ford 460 is a common cause of oil leakage. While this item wears down naturally over time, low oil levels or infrequent oil changes can cause the seal to wear down more frequently and quickly than in properly maintained engines.
Furthermore, worn bearings, crankshaft wear, or a faulty PCV system could be the source of seal failure. Allowing an automobile to sit for an extended period of time without driving it might cause the seal to dry out, become brittle, and leak.
Symptoms of a Rear Main Seal Leak
- Oil puddles under the automobile near the back of the block
- Engine oil is low.
Because of the placement of the seal and the only symptoms being oil spots in your driveway, rear main seal leaks are typically difficult to detect. Unfortunately, replacing the rear main seal is a major undertaking that necessitates dropping the gearbox and removing the oil pan.
There are various more options for patching a rear main seal leak, such as BlueDevil Rear Main Sealer. These additives are mixed into the engine oil and are meant to seal the leak. Because the sole issue with rear main seal leaks is oil loss, and replacing the seal is a nuisance, it’s well worth the effort to try to plug the leak before replacing the seal.
4. Exhaust Manifold Bolt Issues on a Ford 460
The exhaust manifold is the initial component in the exhaust system and is a thick piece of cast iron that attaches right up to the block. It transports exhaust gases from valves to exhaust piping. It is prone to extremely high temperatures since it is fastened to the block and flows hot exhaust fumes.
Metal passes through heat cycles, which are the ongoing heating and cooling of metal. When you start your engine, the metal heats up and then cools down when you switch it off. Metal expands when heated and compresses when cooled. As a result, the 460 engine’s exhaust manifold is constantly expanding and shrinking.
This expansion and contraction can cause metal warping or cracking, resulting in exhaust leaks. Furthermore, the bolts that hold the manifold to the block frequently fall off as a result of the same heat cycles. Broken nuts can detach the manifold from the block, allowing exhaust air to leak. Exhaust leaks lower backpressure and induce vacuum leaks, both of which have a significant impact on performance.
Symptoms of a Ford 7.5L Exhaust Manifold Failure
- When in the cab, the exhaust noise is louder.
- Cabin exhaust fumes
- Inadequate acceleration
- Power loss and overall bad performance
If you break a bolt, simply replace it; however, getting the broken bolt out of the block may be difficult. If the manifold is damaged, distorted, or leaking, a new manifold is required. It is customary to replace the manifold with a set of headers rather than an OEM part.
Headers are similar to exhaust manifolds, except that each valve or cylinder has its own exhaust piping. Manifolds combine all of the air into one pipe, whereas headers retain them separate. The separation also helps to keep exhaust gas temperatures, and thus overall engine temperatures, lower.
5. Failure of the Ford 7.5L Oil Cooler
A factory oil cooler was utilised in Ford’s 460 engines. An oil cooler’s aim is to lower the temperature or remove surplus heat from motor oil. Because engine oil circulates throughout an engine, it can assist cool the block, internals, and numerous other engine components.
The 460 employs a heat exchanger oil cooler design. The oil cooler draws oil into internal tubes, which have engine coolant running on the exterior. The coolant aids in the cooling of the oil as it passes through the tubes.
Because the oil and coolant are both flowing via the same system, failure might result in coolant and oil mixing, causing catastrophic engine damage. The oil coolers on the 460 are known to fail internally, causing the two fluids to mix. The coolant is then recirculated into the engine. Because coolant does not have the same lubricity as oil, it might deprive internal components of necessary lubrication, resulting in major internal difficulties.
While inadequate cooling system maintenance is the most prevalent cause of this issue, removing the OEM oil cooler or replacing it with an aftermarket system is a common solution for 7.5L owners.
Related : The 5 Typical GM LS1 Engine Issues
Symptoms of Oil Cooler Failure
Among the signs of Ford 460 oil cooler problems are:
- Oil cooler coolant or oil leaking
- The presence of oil in the cooling system
- The oil system’s coolant
Other indications, such as engine knock or exceptionally poor performance, indicate that there has been internal damage. If the oil cooler fails, you must stop the engine immediately and cleanse both the cooling and oil systems.
Ford 460 7.5L Reliability
The 460 engine has been around for 30 years for a reason: it is incredibly reliable. While we mentioned several frequent difficulties with systems such as the oil cooler, water pump, gaskets, and seals above, the bulk of these problems develop naturally as a result of age. While regular maintenance might help these parts last longer, the majority of them are classic failure areas on any old, high mileage engine.
The 460 engine is exceptionally robust in terms of its block, heads, valves, pistons, and other internals. The majority of this engine’s troubles arise from supporting systems rather than the engine’s core.
Overall, Ford’s 7.5L 460 engine is very dependable. As with any 25+ year old engine, the most of the troubles it encounters today are the result of age and heavy mileage. The block and major engine components may easily sustain more than 300,000 miles.
