by Pat Yanahan


Finishing assembly of cleaned engine and painted sheet metal

All that grease, oil and dirt in that dreaded cavern called the engine compartment just looks like too big a project to take on. Well, it is big, but once you do it, it is relatively simple to maintain. On the older Porsches you can see the engine and get your hands inside. With the newer 911s you have to take off fans and plastic covers to get to them. And the Boxsters are even more challenging, but it can be done. I have enlisted experts who are both local and national Concours winners who share similarities on how and what products to use. If you’re serious about cleaning the engine it is best to take it out completely. 356s, 912s and older 911s take about 45 minutes to remove the engine. Newer models can vary up to 90 minutes. We have several professional mechanics in the area who can aid you in this process and it is worth the time and money to do it safely and correctly. If you don’t want to go to this extreme it can be cleaned with small hands and small cleaning tools. Always wear eye protectant and gloves. The first challenge is to remove the dirt and grease. The philosophy on the correct cleaning product is not to use household cleaners but rather the serious professional stuff. If the engine is out you can replace the decaying foam firewall sound barrier.

John Diwik leads us in the recommendation of the Wurth Citrus based Degreaser that is eco-friendly, easy on the hands and the driveway. It smells like oranges and removes grease, grime, dirt and factory cosmoline. This product is safe for most surfaces and won’t harm paint. It can be used full strength or diluted as the application requires. It just needs to sit for about ten minutes to do its magic. He likes to use it with a soft cloth or brush to get the embedded dirt, grease and cosmolene free from the surfaces of the
engine. Where Oil-Flo Solvent Cleaner (Titan Labs) takes cosmoline off immediately, Citrus Degreaser might take a few applications to get the same result. Hank Weil’s suggestion is to change cloths often so that you clean up the mess and not spread it around. Make sure you remove all residue with clean rags. He’s not a fan of using a power washer on the engine, but he has had success having an engine steam cleaned.

We all recommend Simple Green All-Purpose Cleaner (Sunshine Makers) as a good all-purpose cleaner for rubber, plastic and metal surfaces. It can be sprayed full strength on the wiring, hoses and other components. Agitate the surfaces with a soft brush after spraying, it helps to loosen the dirt. Once the cleaning process is completed, the soap residue and dirt can be misted off with distilled water or lightly sprayed with a hose.

Underside of Engine

Bottom view of reinstalled engine

If you don’t have access to a lift for underside cleaning, you can use a jack, but absolutely stabilize the car on jack stands and blocks of the proper load carrying capacity. Eye protectant is mandatory when lying under your Porsche.

Michael Grove counsels that the underside is as important as the top, so use the same attention to detail and look at all nooks and crannies. Stiff bristle bathroom/kitchen brushes works great for initial underside cleaning. Lacquer thinner can be used for removing old sprayed on clear coat (use sparingly and with caution). Mask off and use plastic to protect surrounding areas when using aggressive leaners or water. Hank Weil recommends wearing clean white cotton gloves after the initial cleaning to prevent parts getting dirty again. Use clean cloths and shop rags for every cleaning. Michael Grove cleaned his engine case with commercial aluminum cleaner. It gets into the porous surface and brightens to “as new” condition, as shown in the accompanying photo. Several good brands are available, including products from Wurth.

Ron Bean uses Sonax Car Wash to clean painted metal surfaces and then dresses with Griot’s Speed Shine to maintain these surfaces. He also uses WD 40 on CAD plated parts, i.e. hood latches, hose clamps, etc.

John Diwik also recommends Instant Shine Aerosol Detailing Spray (AR Supply, Inc.) as a great detailing spray that can be sprayed on wiring, hoses, plastic housings or anything plastic or rubber. Just spray it on and wipe it off; it leaves the area looking like new. You can spray hard to reach area and just leave it. Whenever possible, wipe it off afterwards, so the area doesn’t look too shiny. For the same reason, this product should not be used for tires or interior plastic components.

The hardware can be Cadmium Yellow Zinc, nickel, chrome, or stainless steel; you can clean,replace, or re-plate. New metric hardware and re-plating companies are right here in Chicago. The older 911 fans and housings will never look good. Just clean and do not coat or paint. The muffler high temperature exhaust paint, in the correct factory grey is available from Stoddard, or you can ceramic-coat the exhaust manifolds in the correct color. Some judges will catch this and take points off.

This is a big project but worth the effort, though these were just the highlights. You can contact any of our experts or call and I will give you more details, products and sources that are reputable.