My engine has some that oil/dirt grunge in a few areas that I would like to clean. With all of the electronics, I want to be careful. Normally I would heat up the engine and hit it with Gunk then carefully hose it off.

 

If it's an LT1, don't get water anywhere near the Optispark. (Tons of threads on that topic.)
Otherwise, your favorite cleaner, elbow grease and common sense should suffice. Don't use a power washer. And like you said, watch the electronics.

 

Engine Compartment Cleaning

I recently did something I’ve wanted to do for the past year, cleaning and detailing my engine compartment. I accomplished this using two steps over two evenings. Although I make some specific reference to the C5, these cleaning instructions will work just fine on any year Corvette.

Before I go any farther I wanted to talk about water and your engine compartment. When hosing down your engine compartment it’s best to use a light or misting spray of water. Don’t go in there shooting around a strong jet of water. Go easy around the alternator, any exposed electrical connections and the battery compartment. The CPU on the C5 is located under the battery; so filling that area with water is not a good idea!! I did my wife’s Grand Prix and my Corvette using the following procedures without any type of problem, and I used a good amount of water. This doesn’t mean that you won’t have problems though if you aren’t careful.

The first step is cleaning. Although my engine compartment was pretty clean to start with I first gave it a pretty thorough hosing down to remove any dust. The next thing I did was to give it a coating of Zep Citrus Cleaner that I got from Home Depot. I did this to remove any grease or oils. Many people also use Simple Green for degreasing but I was curious how the citrus cleaner would works and it did just fine. If your engine is heavily soiled you may want to do some light scrubbing to remove the grease and oil.

After letting the citrus cleaner sit for a few minutes I once again hosed everything off. The last thing I did was use my air compressor with a blower attachment to remove as much water as I could. You could also use a leaf blower, and some people use cans of compressed air for this. Once I was satisfied with the water removal I let the car sit over night.

Now comes the fun part: detailing your engine with what I call the Windex treatment. This treatment allows you to shine up every exposed area of your engine compartment without touching a thing. Be sure to start this treatment on a DRY engine compartment. I started it while our Grand Prix’s compartment was still wet and it didn’t work right. This is why I let the car sit overnight after the initial cleaning

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Start the car and let it idle for 5 minutes to warm it up and then shut it off.
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Using a vinegar-based glass cleaner like Windex, amply spritz the beauty covers, radiator shroud, hoses, etc. The more the better.
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Close the hood and take a break (I waited 15 minutes).
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Take your garden hose and wash off the glass cleaner. Don’t drench the engine, just spray lightly. Go easy around the alternator, the battery and any exposed electrical connections.
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Spray Armor-all or equivalent (I use 303 Aerospace Protectant) over those same surfaces. Avoid the belts and go easy around anything electrical. Use a lot on the fender covers.
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Close the hood and keep it closed for at least 10 minutes (I kept it closed for around 20-30 minutes while I washed the rest of the car).
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When you open up the hood it will look brand new.

That’s all there is to it. The only thing I had to do was blot up some 303 Protectant that had puddled up here and there. Take a look around and make sure everything is shined to your satisfaction. If anything was missed you can always touch it up with a rag and whatever shine product you are using. I did my compartment about a month ago and it’s held up great. For follow up maintenance I will probably just blow some air in there periodically to remove any dust.

Well that wraps up the car care section. I hope you found something useful here, and if you have any questions or concerns you can email me at jl@nycap.rr.com. Thanks for looking!

 

You can shield the opti by putting a plastic bag (like a grocery bag) unfer the waterpump and gently worlikg it around the opti with a screwdriver, than do the same thing with come old towels. The opti will stay nice and dry.

IMO, gunk stinks and you can smell it n the car for days. The cheap degreaser at Walmart works just as well. But, either one will cause your rubber hoses to turn whiteish, pain in the *** to remove that.
I use Simple Green, toothbrushes,etc.

As said above, no powerwash, that includes the hose, it's not for blasting, just for lightly rinsing off the degreaser.

 

After I dug the link up, I realized I had forgotten the vinegar based cleaner step. This make everything shine like new money! I know what I will be doing this weekend!

 

Thanks guys, it would figure the area around the opti spark is the worst. I just bought the car and think it must have a minor valve cover leak (96 LT-4). I spent the weekend replacing the air cleaner with K&N, all 8 injectors with Bosch III's and a new fuel filter & air foil... all the things that are supposed to double the HP of the car I want to personally thank GM for mixing metric and English fasteners. It makes for great fun. I will try these tips this week end. Thanks!!!

 

Did you say DOUBLE the HP ? all kidding aside did you notice any gain ?

 

Haven't taken her for a spin yet. Plan on doing that today. So far the idle seems smoother. I know it will take a while for the computer to relearn its stuff. Not expecting anything earth shattering, the car already has plenty of zip. I am considering long tube headers as my only other mod I would consider but still thinking.

 

I learned to use warm water to rinse the engine. I used cold water, and got condensation inside the distributor...no start.

 

I posted a similar question over in the Car Care/Detailing Forum under the General Forum tab. Several folks suggested using a Steam Genie on the built up grimy areas. More exacting than a water spray. Be careful around rubber/plastics to not melt anything.

 

Now that I think about it I do have a steam cleaner and a neat little device that I picked up at Harbor Freight that works like a paint gun. Hook a air line up to it and place is draw tube in a bucket of water with degreaser or what ever and spray away. I does direct the spray much better but I am still worried about the opti spark. That area of the engine is covered in grime.