Unfortunately, the LT5 engine paint will instantly stain if you give it a dirty look. It's not very durable. The two main causes of stains on the engine are coolant and oil. If you get coolant anywhere on a painted LT5 surface, you better make sure you wipe it off ASAP because if the engine is hot.....you can be sure it's going to stain.
To clean a dirty LT5 engine, do NOT use engine cleaners or steam cleaners (my own personal recommendation). Engine cleaners/degreasers are usually caustic and you can guarantee that they will permanently stain the LT5 engine. I simply take a damn cloth and wipe the engine down. In my opinion, steam cleaners introduce an unnecessary amount of moisture that can accumulate under the plenum and down in the engine-V where the starter is located.
At the back of the LT5 engine, in that V, is a small hole drilled into the block to allow water to escape. On earlier LT5 engines, the hole was not big enough and over time, road salts and oils would form an amalgam with any condensed moisture that got down in there and plug the hole. If water gets into that V, and can't drain off, and is not given enough of a chance to burn off, it can corrode the starter contacts, and you'll soon be replacing your starter. On the newer ZR-1s....I want to say '93 and up, the hole was supposedly made a little larger, but I still wouldn't take the chance.
If you're trying to remove caked up grease or dirt that is difficut to remove, you can try using Simple Green.
HOWEVER, be warned, if you use Simple Green, make sure you go over the area you cleaned, with a cloth dampened with water. Simple Green will most definitely stain your engine if it's left on the paint for an extended period of time.
If your anal like I am, you can also Q-tip your LT5 engine. Yes, I'm serious....Q-tips. They are extremely handy for getting into those hard to reach spots.
To help keep the engine clean and protected, I wax my LT5 engine just like I wax the body of my ZR. One coat of Meguiars #7 Showcar Glaze, and then one coat of Meguiars #26 Yellow Wax. To keep it clean, I occasionally, use Meguiars Quick Detailer. I simply spray some on a rag and wipe the engine down. I never spray anything directy on the engine - always on a cloth first, then wipe. Now, I'm not saying that this process will work for everyone, but from my 10 years of ownership experience and 28K miles, it's worked very well for me. Below is a picture of my engine:
Yes, I do drive the car - hard when given the chance, and no, I don't keep it parked in my living room. :L
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steve
