Frank A. writes:
This is not a question about mechanical malfunctions exactly, but more about the avoidance thereof. I’d like you to give us your advice on engine cleaning. Clearly, it’s not a matter of putting a baggie over the carburetor and sticking a hose in there anymore!
The engine in my ’03 Town Car is looking dingy, but I don’t want to do anything prejudicial to the, I guess, thousand or so computers under there. I’ve noticed that practically all the shops in my area that used to advertise steam cleaning have quit on it, so that makes me think even the pros find this tricky nowadays. What do you think?
While not as important as regular oil changes on the inside, having a clean shop under the hood is a great idea. Clean engines make visual inspections and repairs easier, keeps moving parts (like belts) alive longer and might even run cooler than dirty ones.
That said, the idea of steam cleaning an engine died for all the right reasons. Underhood electronic connectors are fairly waterproof, but not water vapor proof. You can cause all kinds of temporary electrical shorts by steam cleaning an EFI-controlled engine.
The solution? There are several: to get a really dirty motor clean, get a bottle of foaming engine cleaner from a parts store. Don’t use on a hot motor, but a warm one helps cook off the grime: shoot the cleaner anywhere you see caked on gunk, using a toothbrush to break it free. Use Simple Green (or equivalent) on the rest of the motor, avoiding the belt and cooling passages on the alternator. Let soak for 5-10 minutes, while you scrub the ugly spots. Wash it all off with a garden hose, don’t go crazy with water pressure, either.
Once the motor is clean, do the occasional touch up at your local coin-op car wash, using their “hot” engine cleaner. That stuff works wonders, even leaving a low-luster shine to boot. It’s cheap and keeps your neighbors from silently judging you.
Bonus! A Piston Slap Nugget of Wisdom:
Take off any and all plastic engine/radiator shrouds, so you clean all the areas that need to be seen when it’s time to get something fixed. While you’re in there, check all vacuum lines, the PCV valve and anything else that normally needs attention after 5+ years of service.
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