A diesel engine, which is an internal combustion engine that uses heat to ignite fuel, has an average service life of about 10 years. Diesel engines deliver both power and a high level of performance. But wear and tear over time on the engine components can lead to mechanical problems and performance failure. As you start to notice problems occurring with your diesel engine, the best way to address them might be by getting an engine overhaul. This procedure involves taking apart the engine, identifying faulty parts and replacing them, cleaning all the engine components, and then rebuilding the engine. An overhaul can increase the performance, power, and longevity of your vehicle. Use this guide to help you decide when to have your diesel engine overhauled.

If you notice any of these problems, it is very likely time to bring your vehicle in to get an overhaul immediately:
- Your engine has spun a rod bearing. This is one of the worst failures that can occur inside your diesel engine. A spun bearing usually seizes itself around the crankshaft, causing damage to the rod journal and the connecting rod. A broken rod moving around inside your engine can do a lot of damage. A spun bearing is usually the result of large operating loads in combination with significant lubrication loss in the crankcase.
- Your engine has very low or no oil pressure. A fuel or coolant leak can contaminate the engine oil, which leads to a high oil level in the crankcase. This almost always indicates that excess fluid is leaking somewhere else inside the engine. The engine must be taken completely apart to determine the source of the fluid leak.
- Your engine has dropped a valve. This is an all too common and critical fault of a diesel engine. A dropped valve happens when a valve head becomes bent and then shears, falling into the cylinder. This results in significant damage to the entire piston-cylinder-valve system.
If you notice these symptoms, it is a good idea to talk to a mechanic about the possibility of getting an overhaul:
- Your engine has high blow by. Blow by is the compressed fuel and air mixture in the combustion chamber leaking past the piston and entering the crankcase. High blow by is problematic since it reduces the engine’s power and causes a build up of gas pressure in the crankcase. Too much fuel being injected into the combustion chamber is usually accompanied by white smoke coming out of the exhaust pipe.
- Your engine is consuming a lot of engine oil or coolant. If your diesel is suddenly using up more oil or coolant, it could be from a variety of problems. This can include an oil leak, cracked cylinder head or gasket, or faulty cylinder liners and O-rings.
- You have put a lot of miles on your diesel and are getting lower fuel efficiency. Vehicles with a diesel engine should come with a recommendation as to when you should get an engine overhaul based on mileage. Consult your owner’s manual or ask an expert about what they would recommend given the year, make, and model of your vehicle.
These are just some of the issues that can arise and indicate that it is time to have your diesel engine overhauled. If you notice any of the above problems or think that you might need an overhaul, you should bring your vehicle to a trusted mechanic with ASE certified technicians.
If you are near the Meridian, Idaho area, and have any diesel service or repair needs, Gem State Diesel is ready to serve you. With more than 30 years experience in the automotive industry, owner John Nesmith has assembled a team of highly trained mechanics. Book an appointment online or call us at (208) 957-6106 today.