Painted Fan Housings and Other Pet Peeves

engine with painted fan housing

I look at a lot of car photos. Specifically, Porsche air cooled cars because that is what I am interested in. What I look for may be very different than what you look for in the photos. Yes, there are a lot of pictures of beautiful Porsche cars, shiny paint, great decals, body modifications and fabulous wheels. All well and good, but what I’m looking for is a good photo of the engine bay.

Form following function, this is art and beauty that functions, but what I see in the engine bay brings into question the functionality. When I notice nonstock parts or a painted fan housing, I wonder, has it been done correctly.

Bunch of colorful fans and housings

What is wrong with Painted fan housings?

Maybe they have been done correctly maybe they have not, it is not something that can be determined by just looking at a photograph. The bright red, pink, purple, green, or whatever color raises the alarm bells for me, and I take a closer look at the whole engine bay. The fan housing is part of the engine electrics. The fan housing is a ground point for the ignition coil and the alternator. When a fan housing has been painted correctly it will not have paint on the bottom side where it contacts the engine case, or where the coil mounts. If you do not have good grounds for the ignition system and alternator, it may cause damage to the alternator, and if all the energy cannot get to the spark plugs it may damage the coil and or the CDI box.

The alternator rectifier relies on a good housing ground to correctly convert AC voltage to DC voltage. A poor ground here can result in voltage spikes both positive and negative that may cause system damage to both the alternator and ignition system.

Spark plug wires

Colored ignition wire sets are my next pet peeve. Anything but a solid core factory ignition wire set may cause damage to the CDI and or coil. Solid core wire sets have the same resistance no matter the length, and the resistance shapes and slows the spark energy to the spark plug.  Usually aftermarket colored wires are not solid core and often have the wrong resistance value. The resistance per foot may also affect timing, by having different resistance on different length wires causing the energy may arrive at a different time.

Colored wires are another red flag.

Aftermarket changes, like switching from a single plug ignition system to a twin plug system or changing the fuel system to carburetors from an fuel injected motor, show up in the engine bay photo and get me to thinking about functionality. A beautiful car is great but if it has engine issues there is no point to the beauty if it can’t drive perfectly. I would prefer a beater car with a stock tidy engine bay over a garage queen with modifications, but hey that’s just me.

About the author

Being married to a mechanic has its benefits, I expect all work to be done cheap and straight away. Not only has it spoiled me, it has opened my eyes to the cars, parts and people that go along with running an automotive business.  I had a completely non-automotive career in the art field and did my own thing for many years. As time went on, life changed, and the automotive business became the family business. I became fully involved in the day to day of running an online auto parts store for the last decade. With our new move into the informational realm I feel ready to express more opinions from my point of view and my experiences in the automotive world.

Sarah D


1 thought on “Painted Fan Housings and Other Pet Peeves”

  1. Very good article. I always liked a painted up engine but did not realize you can spot some real problems by looking a little closer and asking some good questions.

Comments are closed.

Want More?

Get the coolest tips and tricks today

Subscribe to our email list and get regular notifications of new videos and blog articles on how to repair your own car.