What You'll Learn
Aussie Conditions
Look, I get it. The idea of pointing a hose at your engine feels about as smart as poking a brown snake with a stick. But after 15 years in the trade, I can tell you that a clean engine runs cooler and makes it way easier to spot leaks before they leave you stranded on the side of the Bruce Highway. This guide is for anyone who wants their engine bay looking mint without the stress. We'll cover everything from dealing with baked-on grease to protecting those sensitive sensors.
Why Bother With the Engine Bay?
The Gear You'll Need
What You'll Need
While you're here...
Preparation: The Most Important Bit
Check the temperature
Never, ever wash a hot engine. If you've just come back from the servo, pop the bonnet and let it sit for at least 45 minutes. You want it 'luke-warm' at most. If it's too hot, your chemicals will flash dry and leave nasty spots on your paint and plastics.
Clear out the debris
Before you get things wet, grab a vacuum or even just your hands and clear out all the dead leaves and gum nuts trapped near the wipers and the firewall. This stuff holds moisture and causes rust.
Cover the sensitive bits
This is where people get nervous. Use your foil or plastic wrap to cover the alternator, any exposed air intakes (if you've got a pod filter), and the battery terminals if they're exposed. If you've got an older car with a distributor, wrap that up tight like a Christmas present.
Watch Out
The Dry Brush Trick
The Main Event: Step-by-Step
Initial Rinse
Give the whole bay a gentle misting. You aren't trying to blast dirt off yet, just getting it wet so the chemicals can do their thing.
Apply Degreaser
Spray your degreaser on the heavy areas, the lower parts of the engine, the strut towers, and the firewall. Leave it for 3-5 minutes, but don't let it dry!
Agitate with Brushes
This is where the magic happens. Use your small brushes to get into the nooks and crannies. Focus on the plastic covers and hoses. You'll see the brown Aussie dust just start to lift.
The Underside of the Bonnet
Don't forget the 'ceiling'. Give it a spray with APC and a light scrub. Be careful with the insulation pad, if it's old and crumbly, just leave it alone or you'll have a mess.
The Rinse-Off
Using low pressure, rinse from the back of the engine bay towards the front. Keep the nozzle moving. Don't linger on any electrical connectors.
Check Your Work
If you missed a spot (and you probably did, happens to the best of us), hit it again with some APC and a brush while it's still wet.
Dry Everything
This is the most critical step. Use a leaf blower or compressed air to blow water out of every single bolt hole, electrical plug, and especially around the spark plugs. Spend 10 minutes on this. Your car will thank you.
Towel Dry
Wipe down the flat surfaces and the paint on the inside of the guards with your old microfibres.
Remove Protections
Take off all that foil and plastic wrap you put on earlier. Don't forget the one you stuffed in the air intake!
Start the Engine
Fire the beast up. Let it run for 5-10 minutes. The heat from the engine will evaporate any remaining moisture you couldn't reach with the blower.
Watch Out
The Finishing Touch (The Secret Sauce)
The 'Mate's Rate' Inspection
Common Questions I Get Asked
Can I do this at a self-serve car wash?
Will I void my warranty?
What if the car won't start afterwards?
How often should I do this?
Do I need to cover the battery?
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