What Are the Benefits of Having an Engine Rebuilt Instead of Replaced? | YourMechanic Advice

What Are the Benefits of Having an Engine Rebuilt Instead of Replaced?

Most catastrophic engine failures can be avoided through routine service and maintenance. In most cases, an overheating condition or broken oil pump will cause internal components to fail, which can result in a non-operable car that will require a new engine or engine rebuild.

Although it might seem easier and more cost-effective to replace your older engine, the truth is that even if the replacement engine is from the exact same car as yours, there could be many potential hurdles to overcome.

Listed below are a few of the things to consider when you're in the market for a new engine or having your existing engine rebuilt by a professional engine mechanic.

What are the most common causes of engine failure?

In most cases, engine failures are caused by one root source: heat. Whether it's a failure of the cooling system to keep the engine at an optimal operating temperature, or a lack of oil pressure or clean oil to lubricate moving parts which creates excess friction, most major engine failures can be traced back to these events. In general, there are a few specific issues that lead to engine failures including:

When any of these occur, different parts of the engine will become damaged. If the engine overheats, it's common for head gaskets to fail which introduces coolant inside the engine block within oil galleys. This dilutes the engine oil and causes a lack of lubrication, or excessive heat.

Knowing what caused the engine to fail is the first step in determining whether or not an engine rebuild or replacement is needed.

What Happens When an Engine is Rebuilt

A rebuilt engine involves removing the engine from the vehicle and completely disassembling it from what's commonly referred to as "carb to pan". This is an older description when engines had carburetors instead of fuel injection systems they have now, so today it would be referred to as "Injector to Pan," with the pan being the oil pan. Once the engine has been disassembled, cleaned, and inspected, all damaged parts are replaced with new or refurbished replacement parts. All new gaskets, seals, and lubricants are used in the assembly of the rebuilt engine that will meet OEM standards.

The most common components to be replaced include O rings, bearings, gaskets, seals, timing belt or chain, valve springs, and the oil pump. Major parts are replaced only if they are needed, and often include camshafts, crankshafts, and pistons.

If severe damage occurred to your engine, the engine block may have to be bored to align the crankshaft main bores. The cylinders may need to be bored to fit new pistons. This is more extensive work, but it will allow the engine to work once again. In general, there are only two instances where the choice is not an option.

*The engine block has been damaged internally due to broken connecting rod or crankshaft

*The exterior of the engine block has been cracked or "windowed" - which happens when an internal component punches a hole in the block.

Under other issues, having the engine rebuilt is a realistic option

The Advantages of Rebuilding

Once the engine is rebuilt, you know everything has been closely inspected and it has many new parts. It will extend the length of life for the engine. How long it will last depends on how many components were replaced. Another benefit is that you are recycling engine parts to help reduce the amount of scrap in the environment.

However, arguably the best benefit of engine rebuilding is the connectivity and compatibility with the existing ECU and electrical system. The ECU is programmed to communicate with the engine originally installed in the vehicle. In many cases, when a new engine is installed, the ECU has problems connecting and communicating with the new engine. In most cases, an engine swap will require either a reprogramming of the ECU or replacement.

If you have the opportunity to choose between a repair or replacement, it is always advised to repair the existing engine with new, OEM replacement parts to reduce the potential of compatibility issues.


Next Step

Schedule 75 Point Safety Inspection

The most popular service booked by readers of this article is 75 Point Safety Inspection. YourMechanic’s technicians bring the dealership to you by performing this job at your home or office 7-days a week between 7AM-9PM. We currently cover over 2,000 cities and have 100k+ 5-star reviews... LEARN MORE

SEE PRICING & SCHEDULING

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Recent 75 Point Safety Inspection reviews

Excellent Rating

(427)

Rating Summary
392
16
10
1
8
392
16
10
1
8

Pardeep

20 years of experience
812 reviews
Pardeep
20 years of experience
Ford Fusion - 75 Point Safety Inspection - San Jose, California
I have ordered a 75-point inspection of the car since my dealership claimed it had an oil leak and the timing cover replacement was due (this kind of repair costs in the ballpark of a thousand dollars). I mentioned the need for a second opinion on that since the car had been bought relatively recently from that dealer (certified pre-owned) and not very actively used. Pradeep performed the safety inspection in a very timely manner and addressed my main question by honestly concluding that there was no leak but just some dust collected over time. This has saved me much time and money. Finally, I was also very glad to learn a tip on how to find a matching paint for a body scratch from him.
Ford Escape - 75 Point Safety Inspection - San Jose, California
Pradeep immediately found the suspension problem I was worried about and fixed it. We had just purchased this car and now feel a lot better about it now that he has checked it out.

Honorio

18 years of experience
828 reviews
Honorio
18 years of experience
Hyundai Accent - 75 Point Safety Inspection - Sunnyvale, California
Honorio not only told me what is going on with the car but was so honest about everything. Looking forward to having Honorio taking car of my requests.
Acura RDX - 75 Point Safety Inspection - Palo Alto, California
Honorio went above and beyond my expectations. He was honest about which repairs needed to be done even though my service revision decreased his income. Will absolutely use again!!!! Thank you!

Robert

3 years of experience
46 reviews
Robert
3 years of experience
Nissan Versa - 75 Point Safety Inspection - Lakewood, Washington
Robert is a rockstar. I can't express enough (again) the quality of his work and his ability to work around our schedules here. Honest, professional and courteous. I would recommend his services to any and everyone.

Juan

11 years of experience
25 reviews
Juan
11 years of experience
Mazda Protege5 - 75 Point Safety Inspection - Vacaville, California
Professional, clear, & courteous when discussing results of inspection & recommendations going forward. If I still live in the area when I need to do future services, will definitely book again.

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

Related articles

Does Running My AC in the Summer Keep My Engine Cooler?
When When you engage your air conditioning in your car, it is usually summertime and hot outside. Air conditioning serves to remove heat from the inside of your vehicle by circulating a refrigerant through the evaporator core in your dashboard,...
What's the Difference Among OES, OEM, and Aftermarket Car Parts?
Aftermarket auto parts can be good quality and cheaper than Original Equipment Supplier (OES) and Original Equipment Manufacturer (OEM) car parts.
Symptoms of a Bad or Failing Crankcase Vent Filter
Common signs include oil leaks, excessively high idle, and a decrease in engine performance, power, and acceleration.

Related questions

Engine has sludge.

Replacing an engine is a very costly repair. Oil sludge often results from contaminated or neglected oil. Not having oil changed at regular specified maintenance intervals will cause sludge to build up inside the engine. Sludge if not excessive can...

Drove over large curb - 2015 Kia Rio5

The behavior you describe may only have been a momentary glitch because of the shock to the chassis. However, other damage to suspension, fuel and brake lines or the exhaust pipe might have also occurred. If you would like, a...

Car starts, but dies

If you read your owners manual there is a special procedure to follow after a battery is disconnected or replaced. It's needed to relearn the idle and throttle procedure. If the procedure is not done, then it may take a...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (855) 347-2779 · hi@yourmechanic.com