Polish the motor as well as the motorhome for a neat-looking unit inside and out.
By Bill Hendrix, F761S
We had owned our 1995 coach for several years, and its age began to show in the engine compartment. I had always polished the exterior, including the wheels, on a fairly regular basis but tended to neglect the parts not readily visible. Opening the engine compartment door on the diesel pusher revealed some oil and dirt accumulation, faded paint, and rusty areas. So, I decided to attack the problem with the goal that when I was finished with the job, the engine would appear much like factory new. This meant that just painting everything one color, over the dirt and grime, wouldn’t make it right. If you would like to return the appearance of your engine compartment to a just-like-new look, here are some of the methods I used to clean up and brighten this often-neglected area.
Before you begin any refinishing, it is necessary for the engine and accessory surfaces (including the inner fenders on type C coaches) to be clean and free from any oil or grease. The first preference would be to find a truck wash bay with a high-pressure sprayer using hot soapy water. These may not be plentiful, but I would drive several miles to locate one.
For type A and B coaches, the firewall and the fender liners may be cleaned in the same manner as the engine block. These areas are not inclined to rust and a good cleaning will normally suffice. If oil and grime persists, allow the cleaner to soak and penetrate and then repeat the process. Again, take care to avoid or cover any moisture-sensitive equipment mounted nearby. Plastic bags secured with tape work well for fuse boxes and other small electrical items.
Before you begin the cleaning phase of this project, let the engine and manifold cool, as you don’t want to spray a hot engine and a hot manifold. A warm engine with a cool exhaust manifold is best. Take care not to pressure-spray the electrical connectors on the engine control module, voltage regulator, or any other water-sensitive areas. If your motorhome is equipped with a gasoline engine, the distributor and the carburetor air cleaner should be protected with plastic. Pay attention to the area below the shaft seals, as there is often some oil dribble there.
The advantage to using a truck wash bay is pretty obvious, especially since you don’t have to deal with any ecology issues for the resulting runoff. If you have only a minor amount of oil residue to deal with, and an acceptable place to do the cleaning, there are several products available at auto supply stores for this purpose. Read the labels, heed the warnings, and make sure the product is water-soluble for easy cleanup. If you have a personal pressure washer, use it in moderation with the above precautions. Many engine cleaners will work on a warm engine with a water hose spray for cleanup. The fins and cores on the radiator might be a bit delicate for pressure washing, so rinsing with a water hose would be the safest method of cleaning.
Remember, safety first. Wear a face shield or goggles, long sleeves, a cap, and a pair of furniture refinishing gloves, which will give your hands the needed protection. Often there will be areas that need some hand scrubbing with an old toothbrush, steel wool, or wire brush to get into corners and crannies that are a bit stubborn. If some of the oil residue has been baked into a varnish-like film, try using parts cleaning solvent applied with a rag. Rust may be removed using a small wire brush or some emery cloth. After getting everything clean, let the engine and accessories dry thoroughly before beginning the detail work.
The trick to achieving a professional-looking result is to avoid overspraying, to paint only the individual parts, and to restore them to their original color, or a color very close to original. The engine block itself will have a distinctive paint that may be difficult to match unless you go to one of the engine manufacturer’s service shops and purchase the real stuff. Unless you have a rust problem, this shouldn’t be necessary, as the original paint is very durable and cleanup will normally suffice.
To paint the accessories, gather some old rags, newspaper, and masking tape. Also purchase two or three small disposable paintbrushes and a variety of spray paints that are the appropriate colors to bring those items back to near original finish. There are several very good spray paints available. Over the years I have had excellent results with Krylon and Rustoleum for a wide variety of paint projects. Rattle-can paint is best when used at temperatures of 70 degrees Fahrenheit and above.
Shake the can initially for at least two minutes and frequently during the painting. Two or three light coats, with adequate drying time between, will give the best results. After you have cleaned the engine block, focus on one accessory at a time. Lightly sand the surface with 220-grit sandpaper for good paint adhesion. While sanding, wear a dust mask. Cover all the adjacent surfaces and areas below with rags and newspaper and carefully mask the paint line. If the masking tape won’t stick, you probably still have oily residue that needs to be removed. Usually the bolt heads are a different color, often black. I prefer to paint over the bolt heads while spraying, as masking them off is pretty tedious. The following day, when the paint has totally cured, the bolt heads can be painted again individually with a small paintbrush.
Allow the paint to dry and then remove the rags and masking tape. There may be a spot or two that needs touching up. This can be done with one of the small paintbrushes. Using a piece of cardboard to catch the overspray, hold the paintbrush 2 or 3 inches away from the spray can nozzle. A short blast will load the paintbrush bristles. Then touch up any needed area, repeating with more paint if necessary.
Go to the next accessory and repeat the masking process after the previous paint is dry. Most paint will be dry to the touch in 10 to 15 minutes after the final coat. The pulleys don’t have much surface area and masking is difficult, so I use the paintbrush technique on them. Cleaning and brightening the belts, hoses, and other flexible lines adds a finishing touch.
This may be an all-day project with quite a bit of waiting time in between, but once completed, you will have a cleaner, brighter, cooler running engine, and you will be proud to open the compartment door.