When an engine is no longer serviceable, we have several options for a replacement. Some vehicle makers sell remanufactured engines, for their vehicles. General Motors, Ford and Chrysler have remanufacturing programs.
The engines we buy for replacement offer a high quality rebuilt option. Many people misunderstand and think these engines are new. They sell very few new engines. Instead, they rebuild most OEM replacement engines.
A short block or long block engine?
Other vehicle makers may only sell engine components. For instance, they may sell the short-block. This includes the engine block, pistons, crankshaft and most internal components. They often include the camshaft and timing chain on overhead valve engines. Not included are the cylinder heads, oil pan, and other bolted on components.
By contrast, a long-block includes the cylinder heads and often the oil pan, valve covers and timing cover. A few remanufactured engines also include spark plugs, a water pump and harmonic balancer. They price A short-block less than a remanufactured long-block engine, but after buying the additional parts needed, it may cost far more. A short block is not as desirable as a long-block engine, but may sometimes be our only alternative.
Aftermarket rebuilt engines
Aftermarket manufacturers also offer rebuild engines but these vary greatly in quality. The words rebuilt and remanufactured have no standardized meaning. Many aftermarket rebuilt-motors do not give good service. Because of the cost of replacement when they fail, these engines may be a very poor investment.
A used engine, from a reputable salvage company, is a great cost saving alternative. These engines are original equipment parts taken from salvage vehicles. The used engine is an OEM factory-assembled part. This may be far better than a low-quality rebuilt engine. Used engine prices vary, depending on mileage and how common the engine may be. Used engines usually have everything a long-block contains and often more. This saves assembly time. With a lower-mileage used engine, we gain many additional miles for our vehicle, at a reasonable cost.
Installing a replacement engine
Engine replacement is not easy but a handy amateur mechanic can accomplish it. Most modern vehicles require removal of the subframe and suspension. We then remove the engine and transmission from beneath the vehicle. Without equipment to raise the vehicle and a lifting devices to support the power train, this is very difficult.
On many Ford truck and SUV models, removing the body from the chassis to access the engine is best. This requires a lifting device to raise the body off the chassis. After removing the body, we lift the engine from the frame with another lifting apparatus.
When replacing an engine, we must be extremely careful. Hundreds of small connections are separated and reestablished. Leaving a single ground wire unattached, may cause severe problems. They precisely route many vacuum lines and they must remain exactly as they were. Power steering, cooling system, fuel lines and air-conditioning system are also involved. When doing the job ourselves, we should number the lines and the points where they attach. Taking several photos may also help a great deal.
While the engine is out, the engine compartment is easy to clean. Wiping the area clean, with towels and solvent makes the finished job look far better. Using spray paint, to touch up any spots that need it, adds an attractive touch.
Additional parts to consider
Several parts are easily accessible with the engine out of the vehicle. This is a great time to change any other worn components, at a greatly reduced cost. For instance, engine mounts, belts, hoses and even the water pump are very simple to access.
We must consider costs and benefits when deciding which parts to replace. Things that are likely to fail are good candidates. Replacing small items that require considerable expense to replace later is wise. An example may be the front seal on the transmission. With the engine out, this takes minutes. After the engine is back in the vehicle, the time of replacement may be several hours.
Cost limits always apply when we choose the parts to replace. The amount spent can really rise, with a "change everything" attitude. Some things are easy to replace later or may be unlikely to fail. We normally reuse items such as this.
When we properly replace an engine, the vehicle is ready for many thousand additional miles. An improper replacement is normally the beginning of unending problems. When hiring a company to replace the engine, choose wisely. Usually the more expensive way in is also the cheapest way out.