Stop Ignoring Your Engine Bay: Quick Cleaning Tips

Never, ever wash a stone-cold engine or a boiling hot one. If it's too hot, your cleaner will flash dry and leave nasty white stains on everything. If it's too cold, the grease won't budge. I usually start the car, let it idle for about 2-3 minutes while I get my gear ready, then shut it off. It should be warm to the touch, not 'burn your hand' hot. I learned this the hard way on a black Commodore once, the degreaser dried instantly on the intake manifold and I spent three hours polishing it back out. Never again.

Modern cars are pretty well sealed, but don't risk it. Grab some aluminium foil or a few plastic bags and wrap up the alternator, any exposed air intakes, and the fuse box. Use a rubber band to hold 'em on. Some blokes reckon you don't need to, but for the sake of two minutes of work, why gamble with a $800 alternator? (Trust me on this one).

If you've been out west and your bay is caked in that fine red dust, don't just go in with a pressure washer. You'll just turn it into mud and shove it deeper into the electrical connectors. I always use a vacuum first with a soft brush attachment to get the loose stuff out. Then, use a dedicated cleaner like Bowden’s Own Agent Orange or Meguiar’s Super Degreaser. Give it 5 minutes to dwell, but don't let it dry!

Don't expect the hose to do all the work. You need a couple of cheap brushes. I use a 1-inch paint brush for the tight spots and a bigger wheel brush for the plastic covers. A customer once brought in a Hilux that looked like it had been through a swamp, a bit of agitation with a $5 brush did more work than 20 litres of chemical ever could.