Buyers Guide: Under the bonnet of a used car
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If you’re buying a used car, one of the most important places to check before you pay is under the bonnet.
You don’t even have to be mechanically minded to pick up on clues about a vehicle’s condition, just by popping the hood.
Having a good look here can bolster your confidence when it comes to negotiation time.
Visual telltale signs
A simple glance at the engine bay can reveal a lot, and prompt some questions for your seller to answer.
For example, if there’s
a light cover of dust, with only the oil tank dip stick and radiator caps uncoated, it’s a good sign that only routine maintenance has been carried out.
If there aren’t any servicing stickers for transmission checks and cambelt replacements, ask for details about the vehicle’s servicing and maintenance history.
Look for signs someone has even opened the bonnet in recent time, and keep an eye out for evidence of leaks around gaskets and pipes.
Under the bonnet essentials
Remove the oil dipstick and check its quality.
Dirty oil, or a lack of it entirely, is not desirable, so refer to the service sticker to find out how long it’s been since it was last replaced.
Check the oil and radiator caps for signs of cross contamination of oil and coolant. This will appear on the underside of either of the caps as a thick, creamy substance.
Your radiator coolant should be a vivid colour, typically green or red. If the fluid looks clear or rusty, it could suggest cooling issues or that the vehicle requires regular top-ups. Further road testing will help to assess the cooling system.
A look under the bonnet also brings you closer to the vehicle’s core structure and engine.
If there has been repair work, you may spot overspray or poorly aligned mismatched panels.
If you find these characteristics, investigate the history of the vehicle further with the owner and, if you are not finding all the answers, take the car to a panel beater for an independent assessment
Also listen to the engine with the bonnet up, as unusual or rattling sounds may often be dampened by a vehicle’s insulation when you’re in the driver’s seat.
Signs of metal damage
An inspection of corrosion or rust on any exposed metal components such as nuts and bolts is also a good way to see if a vehicle has been exposed to a corrosive environment or damaged by water.
Similarly loose, missing, mismatched or worn bolts and rounding nuts, along with wear on the guards, may point to a vehicle that has had a troubled past.
Investing in a full steam clean may be beneficial, especially if you’re paying a decent price for the car.
You’ll still be able to identify metal damage and a clean, hot engine can be helpful when it comes to finding the source of a specific leak after a road test. You’ll be able to see exactly what is leaking and calculate what it’ll cost to repair.
It’s all too easy to skip the under-the-bonnet check when you have fallen head over heels for a set of wheels.
We urge everyone to at least do a basic check that will arm you with the knowledge to make an informed decision because further investigation can always be carried out at by an expert during a pre-purchase inspection.