How to Check a Used Engine Before You Buy
An engine is the biggest single purchase most drivers will make for their car, so it deserves a proper check before money changes hands. This guide explains how to check a used engine before you buy — from the engine code to the oil, the coolant and the engine's history — so you can buy with your eyes open.
Call 07961 404768 if you want advice on an engine for your carWhere is the engine code?
Start with the code stamped on the engine itself. It is a short mix of letters and numbers, usually found on the block, and it names the precise engine type in your car. Two cars that appear the same from the outside can carry different codes, so never rely on the model name alone. If the code on the engine does not match your car, do not buy it.
What should the oil and coolant look like?
Pull the dipstick and look at the oil. Clean oil is amber; black oil is old but not necessarily a problem. Oil that looks milky or creamy is a warning sign — it can mean coolant is mixing with the oil, which points to a serious fault. Check the coolant too: it should be clean, with no oil floating in it and no sludge in the reservoir.
What warning signs should I look for?
Look around the engine for leaks at the seals and gaskets, and check the belts and hoses for cracks. If you can see the engine running, listen for knocking, rattling or uneven idling, and watch the exhaust — thick blue smoke means the engine is burning oil, and white smoke can mean coolant is getting into the cylinders. Any of these signs is a reason to ask more questions.
What should I ask about the engine's history?
Ask what car the engine came from, why that car was broken, and how many miles it had covered. A low-mileage engine from a car broken for body damage is a different prospect from a high-mileage engine from a car with mechanical trouble. A seller who can answer these questions plainly is giving you the information you need to decide.
How do I match the engine to my car?
Once you are happy with the engine itself, confirm the match. The engine code, your car's make, model and year, and the fuel type must all line up. If you need an engine for a Japanese car, call Autos Craft Ltd on 07961 404768 with your engine code and car details and we will check stock and prices for your car.
Frequently asked questions
What is an engine code?
An engine code is a short combination of letters and numbers that names the precise engine fitted to a car. You will usually find it stamped on the engine block or printed in your car's documents. Two cars that appear identical can carry different codes, and the code is what decides which engine will fit your car.
What does milky oil mean?
Oil that looks milky or creamy can mean coolant is mixing with the oil, which points to a serious internal fault such as a failed head gasket. It is a warning sign, not a small detail — ask the seller about it, and think carefully before buying that engine.
Should I buy an engine without seeing it run?
Seeing an engine run is the best check you can make, but it is not always possible. If you cannot see it run, check the oil, coolant and seals, ask about its history, and confirm the engine code matches your car before you commit.
What paperwork should I ask for?
Ask what paperwork comes with the engine, such as details of the car it came from, and keep a note of the engine code and any reference you are given. Paperwork will not prove an engine is good, but it helps you confirm the engine is the one you were sold.
Related pages
Want advice on a used engine?
Call 07961 404768 if you want advice on an engine for your carAutos Craft Ltd · 295 Cherrywood Rd, Birmingham B9 4UU, United Kingdom