Can you paint a car radiator?

The car uses a radiator to cool down the engine by eliminating excess heat. Painting a radiator may seem like an easy way to spruce up an old car, but there are some advantages and some disadvantages

What are the benefits of painting a radiator?

These are common questions that arise when one is considering painting their vehicle’s radiator. The short answer is yes, there will be some benefits to painting the car’s radiator. There are a number of reasons why it may make sense for you to paint your vehicle’s radiator, ranging from cost savings to increased efficiency and performance.

The following three sections will cover the material needed before starting with painting a car’s radiator, the specific steps needed during the process, and finally what happens after it has been completed.

Is it safe to paint the car radiator?

Paint is easily prone to damage and can chip off. This can cause a problem if it happens near the radiator’s thermostat, as that will affect its functionality, and cause it to malfunction. You should also make sure that the paint doesn’t go over any sharp edges or corners. 

Painted radiators are also not suitable for old cars, as they could rust after a certain period of time and cause the paint to peel off. If you still want to paint your radiator, make sure you pick high-quality paint that has been made specifically for use on radiators.

What should you do if you want to paint your radiator?

First off, make sure it’s not too hot yet and put a hose over the area where you plan on painting it so that the paint can dry before being applied.

The paint should also not be applied near the radiator’s thermostat, as it may cause the thermostat to stick to the wall of the radiator and interfere with its operation. When painting a radiator, make sure that you use high-quality paint and that you apply it using a soft dry cloth. 

Paint shouldn’t be applied over any sharp edges of the radiators (where it might chip off) as this too can cause damage to its operation. Using stripes is another way to spruce up an old car.

Material needed to paint the radiator

First and foremost, what materials are you going to need? Well, the following are the exact materials that I used during this process:

  • RTV Silicone  – $16.99
  • PSI Paint Scraper – $9.95
  • PSI Paint Brush – $11.99
  • Medium Blending Brush – $12.95
  • Plasti-Paste – $5.99

As you can see, the total cost for this entire project comes to $65.97 (including the Plasti-Paste) but this can vary depending on what materials you prefer. Other than the paint/primer/paintbrush and silicone, these were the only materials I needed. That is not to say it couldn’t be done with a lower-cost substitute for everything.

For instance, if you only wanted to paint your car’s radiator with Plasti-Dip, I would recommend doing so because they are much cheaper than silicone (about $12 cheaper). If you were to paint your radiator with Plasti-Dip, you would need only a gallon of the stuff for what I needed two cans.

Paint process

The following is a brief outline of the process required to paint a car’s radiator:

  1. Clean radiator thoroughly (water and soap)
  2. Shake the can well; apply Plasti-Paste to small areas at a time; wait 10 minutes for it to cure before moving on to the next area.  Tip: Apply slowly because it’s easy to overdo it in one area and have too much there.
  3. When finished, allow Plasti-Paste to cure for 30 minutes (or the time specified on the can) before touching it.
  4. Sand down Plasti-Paste with sandpaper (400 or finer), using a sanding block.
  5. Repeat until the gloss of the radiator is gone and the finish is matte and rough.
  6. Allow curing for 24 hours before applying a second coat of Plasti-Paste (follow steps 1 through 5).
  7. Allow Plasti-Paste to cure for 48 hours before painting the final color.
  8. Apply paint of choice and finish as desired.
  9. Clean thoroughly with water and soap, then dry. Keep the car radiator clean when not in use, which will help it to last much longer.

What are the disadvantages of painting the car radiator? 

Plasti-Paste dries to a clear, hard plastic covering (like plastic wrap). It does not absorb water as the car is driven, and it doesn’t soften in hot weather. This can be a disadvantage if there are extensive amounts of rust on the radiator or an area where it’s possible for the Plasti-Paste to crack and flake away.

Some people have experienced minor peelings from the bottom of the radiator when they drove over an object or did something that caused them to lose contact with the Plasti-Paste. Other than that, it has been reported that no other major problems have been encountered by those who painted their radiators.

It’s possible that one could get a vinyl (plastic) smell if the radiator is not sealed all around. 

Like paint, this stuff doesn’t come with a warranty. If it didn’t work as expected, you’d have to take it up with whoever you bought it from. I would suggest trying to find one of the companies that guarantee their products or going through a reputable store that guarantees its products.

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